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Geotechnical Assessment Report Northbrook Road Subdivision, Christchurch VB Properties 2008 Limited
Report ref: 223094 20 December 2011 Revision 1
Document prepared by: Aurecon New Zealand Limited Unit 1, 150 Cavendish Road Casebrook Christchurch 8140 New Zealand T: +64 3 366 0821 F: +64 3 379 6955 E: christchurch@ap.aurecongroup.com W: aurecongroup.com
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Document ID: 223094 Geotech Report Rev1 Second Issue.docx
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1 Dec 2011 Issue to Client MHD MHD MD JK
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Contents
1. Introduction 1
2. Summary 2
3. Site Conditions 4
3.1 Site Description 4
3.2 Access 4
3.3 Surface Water 4
3.4 Regional Geology 4
4. Geotechnical Investigation 5
4.1 General 5
4.2 Cone Penetrometer Tests 5
4.3 Tests Pits 5
4.4 Environment Canterbury Borehole Logs 6
4.5 Groundwater Levels 7
4.6 Site Walkover 8
4.6.1 Liquefaction Induced Ground Damage 8
4.6.2 Geomorphological Mapping 8
5. Ground Model 10
6. Engineering Consideration 11
6.1 General 11
6.2 Seismically Induced Liquefaction 11
6.3 Liquefaction Assessment 11
6.3.1 Introduction 11
6.3.2 Liquefaction Potential Assessment 11
6.3.3 Liquefaction Analysis Results 13
6.3.4 Ground Damage 14
6.3.5 Lateral Spreading 15
6.3.6 Discussion 15
6.4 Land Classification Technical Categories 15
6.5 Compliance with the Definition of ‘Good Ground’ 16
6.6 Peat 16
6.6.1 Infrastructure 16
6.6.2 Residential Foundations 16
6.6.3 Discussion and Recommendations 17
6.6.4 Proposed Earthworks 17
6.7 General Site Development Recommendations 17
6.7.1 Cut Excavations 17
6.7.2 Earthfill 18
7. Assessment Against RMA 19
8. References 20
9. Limitations 22
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Appendix A
Figures
Appendix B
CPT Logs
Appendix C
Test Pit Logs
Appendix D
2007 Test Pit Logs
Appendix E
ECan Borehole Logs
Appendix F
LiquefyPro Settlements
Appendix G
LiquefyPro Results
Geotechnical Assessment Report
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1. Introduction VB Properties 2008 Limited is proposing to develop a residential subdivision on an area of vacant land located on Northbrook Road, Rangiora. The subdivision site comprises a total area of approximately 18.3ha. The area is predominantly zoned rural land and it is proposed to rezone the land to residential land use. The site is relatively flat and primarily used for pastoral farming. Aurecon New Zealand Ltd has been engaged to provide engineering services for the subdivision, part of which is to carry out a geotechnical investigation. The purpose of the geotechnical investigation described in this report is to identify any geotechnical issues with the subdivision, including addressing potential liquefaction risk, and any remediation options that may be required as part of the residential development. The scope of work was as follows:
• Review of published geotechnical and geological information on the site. • Undertake a site walkover of the proposed subdivision site. • Subsoil testing using machine excavated test pits across the site to provide information on the
upper soil layers and ground water levels. • Carry out CPT’s across the site to provide information on the soil at depth and data to allow
liquefaction assessment. • Based on the geotechnical investigation information, prepare a geological model for the site. • Carry out liquefaction analysis to confirm the liquefaction potential of the underlying natural
soil. • Preparation of a geotechnical report to present the above information, including a geotechnical
assessment on the suitability of the site and an assessment against the Resource Management Act Section 106.
This geotechnical assessment report presents the results of our geotechnical investigations, the geological ground model, our liquefaction analysis and recommendations for development of the site for the proposed subdivision. This work excludes the detailed design of any remediation options which would be dealt with at the detailed design stage of the subdivision development. Our limitations are attached as Section 9 of this report. This report shall be read as a whole.
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2. Summary VB Properties 2008 Limited is proposing to develop a residential subdivision on an area of vacant land located on Northbrook Road, Rangiora. The subdivision site comprises a total area of approximately 20ha. The area is predominantly zoned rural land and it is proposed to rezone the land to residential land use. The site is relatively flat and primarily used for pastoral farming. Aurecon New Zealand Ltd has been engaged to provide engineering services for the subdivision, part of which is to carry out a geotechnical investigation. The purpose of the geotechnical investigation described in this report is to identify any geotechnical issues with the subdivision including addressing potential liquefaction risk and any remediation options that may be required as part of the residential development. The objective of the geotechnical investigation was to determine the nature and composition of the underlying ground conditions and identify the relevant geotechnical issues. The geotechnical assessment comprised of a site walkover followed by the excavation of test pits and the carrying out of cone penetrometer tests (CPT). A review of existing Environment Canterbury borehole records was also carried out. The CPT’s located in the northern third of the site show an alternating sequence of stiff silt and clayey silt overlaying predominately sandy gravels at depths ranging from 4.0m to 6.3m bgl. The upper 2.0m of silt and clayey silt layers are typically very stiff to hard while the underlying layers vary in stiffness from firm to stiff. In the southern and middle third of the site the ground conditions consist of interbedded stiff silt and clayey silt overlying an alternating layer of firm peat and clayey silt at a depth of 2.5m to 3.5m bgl, which in turn are underlain by very dense sandy gravel. A liquefaction assessment was undertaken for a Serviceability limit state (SLS) and Ultimate limit state (ULS) earthquake based on the NZGS Guidelines using NZS1170 The liquefaction analysis identified the following:
• Under a SLS earthquake case the total settlements are very low and it is unlikely there will be any liquefaction induced ground damage. The exception is CPT16, where potential total settlements are in the order of 15mm. This is still within the limits as outlined by the ‘Guidance on house repairs and reconstruction following the Canterbury Earthquake’, dated 20 December 2010.
• Under a ULS earthquake case the total settlements are typically less than 2mm. The
exception is CPT16, where potential total settlements are in the order of 15mm. This is still within acceptable limits under the new ‘Guidance on house repairs and reconstruction following the Canterbury Earthquake’, dated 20 December 2010. It is however noted that during the ULS design earthquake some building damage is likely at this level of shaking regardless of ground conditions and liquefaction potential. Further we note, that no ground damage was noted following the Darfield earthquake that may be considered to be more severe than the ULS design earthquake considered here.
• The calculated settlements across the site are consistent, especially for the CPT’s which extended to significant depths. This would indicate that the potential liquefaction induced settlements across the site are likely to be consistent. The exception the settlements calculated for CPT16 in the north eastern corner of the site. Based on our site investigations we infer that the difference from this localised area to that of other parts of the site is directly related to the underlying ground conditions, of silty sand to a greater depth.
For the Canterbury region the Department of Building and Housing (DBH, 2011) has recently released a new classification system for residential ‘Green Zone’ land on the flat in regard to the liquefaction
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susceptibility. Based upon results of the liquefaction assessment the site can be placed in Technical Category 1. Due to the type and nature of the subsoil conditions, including the presence of organic deposits we suggest that site specific foundation design is undertaken. Pile foundations are recommended. As required under the new DBH guidelines for detailed house design, a building consent investigation will be required for each lot. It is assumed that the infrastructure can be placed within the sand and silt deposits overlying the thick peat deposits. Further assessment of infrastructure will be required at the detailed design stage. For deep and/or heavy infrastructure pile foundations as per the main site may be required. It is likely that the amount of earthworks required for the site will be minimal as the site is essentially flat. Removal of the peat layers is not recommended as it will be time consuming and costly as part of any preparatory earthworks.
Cuts are likely to encounter predominantly silty soil with the potential for sand layers. Any cuts greater than 1.5m in height or groundwater seepages encountered should be inspected by a geotechnical engineer or engineering geologist to confirm the acceptability and apply any site specific treatment, if required. Depending on the nature of the fill material the appropriate compaction standard will need to be applied. A geotechnical engineer should review the compaction standard prior to site earthworks. All areas where earthfill is to be placed should be stripped of topsoil and stockpiled. Slopes steeper than 3H:1V should be assessed by a geotechnical engineer as part of the detail design. If fill depths exceed 0.5m, we recommend a geotechnical engineer carries out an assessment to confirm the affect the fill surcharge will have on the peat. Our limitations are at the end of this report and this report shall be read as a whole.
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3. Site Conditions 3.1 Site Description
The Northbrook Road subdivision is located on an area of land on Northbrook Road, refer to Figure 1 Appendix A. The site has a legal description of Lot 3 DP 39926, with an approximate area of 18.3Ha and is currently being used as pastoral farmland. The site is bounded to the north by a block of residential properties, to the south by Northbrook Road, to the west by Papawai Drive and to the east by pastoral farmland. The main features of the site are as follows (refer to Figure 2 in Appendix A):
• Overall the topography of the site is flat and split up into eight paddocks.
• There is a spring fed stream that starts 170m northeast from the Northbrook Road / Papawai Drive intersection and flows towards the southeast corner of the site.
• The first 70m of the stream bank is lined by large trees. Otherwise the stream banks are bordered by vines and small bushes.
• The stream is approximately 1m wide by 230m long and varies in depth from 0.1m to 0.5m.
• Power lines extend a short distance into the southern half of the site. 3.2 Access
The site can be accessed from Northbrook Road. 3.3 Surface Water
The only surface water feature is the one referred to in section 3.1 above. The south eastern end of the site below the stream is low lying and water tends to pond in this area after significant rain events. 3.4 Regional Geology
The geology of the site is described in the 1:250,000 scale geological map – ‘Geology of Christchurch,” published in 2008 by the Institute of Geological and Nuclear Sciences. The geological map indicates two different material types around the site, refer to Figure 3 in Appendix A. The map indicates the following geology:
• Dune deposits consisting of “brownish-grey river alluvium (Q1d)” are present underlying the site.
• River deposits consisting of “grey river alluvium, comprising gravel, sand and silt, in active flood plains (Q1a)” are located to the north and east of the site.
The GNS Active Fault System database (GNS, 2011a) indicates that the site is located approximately 43km northeast from the Greendale Fault System. Movement on the Greendale Fault System was responsible for the Magnitude 7.1 Darfield (Canterbury) Earthquake on 4 September 2010. The site is also located approximately 30km north of the epicentre of the Magnitude 6.3 Christchurch Earthquake on 22 February 2011 and 31km north of the Magnitude 6.3 aftershock on 13 June 2011 (GNS, 2011b).
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4. Geotechnical Investigation 4.1 General
The objective of the geotechnical investigation was to determine the nature and composition of the ground conditions and identify the relevant geotechnical issues. The geotechnical assessment comprised the following:
• Site walkover by a Senior Engineering Geologist from Aurecon. • 16 cone penetrometer tests (CPT) undertaken by McMillan Drilling Services and supervised
by a Geotechnical Engineer from Aurecon. • 17 test pits excavations to confirm soil and groundwater conditions and supervised by a
Geotechnical Engineer from Aurecon. • A review of 18 Environment Canterbury GIS database borehole logs.
Overall an intrusive investigation density of at least two tests per hectare was achieved. This is in line with the recommendations issued by the Department of Building and Housing (DBH) Interim minimum requirements for geotechnical assessment for liquefaction and land development, dated August 2011. The CPT test and test pits were used to determine the upper soil layers. The ECan borehole logs in the vicinity of the site helped determine the soil profile at depth and showed that the gravel layer is continuous to depths greater than 15m bgl.
4.2 Cone Penetrometer Tests
16 CPT probes were sunk within the site. The CPT tests were undertaken to effective refusal (tip pressure reaching 30MPa) of the rig which generally occurred within dense layers. The depths achieved were typically between 2.95m and 8.40m bgl. The locations of the CPT tests are shown in Figure 4 in Appendix A and the logs are presented in Appendix B. The CPT’s located in the northern third of the site indicate an alternating sequence of silt and clayey silt layers overlaying predominately sandy gravels at depths ranging from 4.0m to 6.3m bgl. The upper 2.0m of silt and clayey silt layers are typically very stiff to hard, while the underlying layers vary in stiffness from firm to stiff. All the CPT’s refused after only limited penetration of the sandy gravels. In the southern and middle third of the site the ground conditions consist of interbedded silt and clayey silt layers, overlying alternating layers of peat and clayey silt at a depth of 2.5 to 3.5m bgl, which in turn are underlain by sandy gravels. The silt and clayey silt layers are typically very stiff for the first 2m, while the peat layers are typically firm. The sandy gravel layers at depth are typically dense to very dense. 4.3 Tests Pits
Test pits were carried out across the site to confirm the continuity of the soil profile, allow calibration of the CPT logs as well as permitting the measurement of groundwater levels. The test pit excavations were undertaken by a 13t digger and generally reached a depth of 3.0m to 4.5m bgl with a maximum depth of 4.8m bgl. Test pits were generally terminated at target depth or when groundwater was
Table 1 - Site investigation density for overall gr ound characterisation
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encountered resulting in the collapse of the pit sides. The locations of the test pits are shown in Figure 5 in Appendix A, and the logs are presented in Appendix C. Test pits in the northern third of the site indicate very stiff silt, overlying medium dense to dense, fine to medium grained, silty sand at depths of 1.5m to 2.5m bgl. These in turn are underlain by firm to stiff clayey silt of high plasticity at depths of 2.5m to 3.5m bgl with gravels at 4.0m bgl in test pit 11 (TP11). Test pits in the southern two thirds of the site indicate generally very stiff silt to depths of 1.5m to 2.5m bgl, underlain by firm to stiff peat of varying thickness ranging from 0.3m to 2.4m. Underlying the peat layer is typically firm clayey silt of high plasticity or medium dense, silty sand. In the southern third of the site, sandy gravels were recorded below the clayey silt or silty sand layer at depths of 2.6m to 4.2m bgl. The sandy gravel layer gets progressively deeper from north to south (i.e. towards Northbrook Road). The exception to this general soil profile is test pit TP12 where alternating layers of very stiff silt, sandy silt and silty sand were logged to 3.4m bgl, which in turn were underlain by a firm peat layer with some tree matter to 4.3m bgl. Previous test pit logs taken in October of 2007 indicate similar ground conditions but with some slight discrepancies between the logs such as certain soil layer depths and the type of soil. The locations of the 2007 test pits are shown in Figure 6 in Appendix A, and the logs are presented in Appendix D. 4.4 Environment Canterbury Borehole Logs
A review of the Environment Canterbury GIS System (ECan, 2011) has been undertaken to identify borehole logs within the general vicinity of the site. A summary of the borehole logs are provided in Table 1 below. The borehole locations are shown on Figure 7 in Appendix A and the logs are presented in Appendix E.
Table 2– Summary of ECan borehole logs
Hole Reference
Distance from Center of Site
(m)
Depth (m) bgl
Summary
M35/0403 680m East 9.1 Topsoil (to 0.3m), Soft Peaty Clay (to 4.6m), Blue Gravel (to 5mm), Brown gravel (to 6.6m), Fine Brown Gravel with Coarse Sand to depth
M35/6653 730m North 15.0
Topsoil with Gravel (to 0.4m), Brown Clay (to 2.4m), Grey Sandy Gravel (to 10m), Brown Clay bound Gravel (to 11.1m), Browny Grey Sandy Gravel (to 13.8m), Brown Clay bound gravel to depth
M35/8026 480m South 10.3 Topsoil (to 0.3m), Clay (to 4m), Brown Clayey Sand (to 5m), Clay bound Sandy Gravel (to 7.2m), Water bearing Sandy Gravel with Clay to depth
M35/8810 520m North 31.3 Topsoil (to 0.3m), Clay and Silt (to 2.3m), Alternating layers of Clay bound Gravel and Water bearing Gravels to depth
M35/9692 790m North 30.5 Topsoil (to 0.3m), Clay bound Gravels (to 10.2m), Sandy Gravels to depth
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M35/11317 220m Southwest 5.5 Topsoil (to 0.4m), Brown Clay (to 2.6m), Peat (to 4.1m), Brown Sandy Gravels (to 4.3m), Water bearing Gravels to depth
M35/11318 365m Southwest 5.7 Topsoil (to 1.5m), Brown Clay (to 3.2m), Peat (to 3.8m), Brown Sandy Gravels (to 4.5m), Water bearing Sandy Gravels to depth
M35/11546 585m Southeast 7.0 Topsoil (to 0.3m), Brown Clay (to 4.2m), Brown Sandy Gravels to depth.
M35/11547 500m East 7.0 Topsoil (to 0.3m), Brown Clay (to 4.2m), Brown Sandy Gravels to depth.
M35/11548 470m East 7.0 Topsoil (to 0.3m), Brown Clay (to 4.3m), Brown Sandy Gravels to depth.
M35/11549 400m Southeast 7.2 Topsoil (to 0.3m), Brown Clay (to 4.1m), Brown Sandy Gravels to depth.
M35/11551 250m East 7.0 Topsoil (to 0.3m), Brown Clay (to 4.0m), Blue Gravels (to 4.3m), Brown Sandy Gravels to depth
M35/11558 400m South 4.0 Topsoil (to 0.15m), Light Brown Clay (to 1.45m), Grey Clay with Organics (to 1.6m), Black Organic soil (to 2.1m), Light brown Silty Gravel to depth
M35/11559 440m South 4.0 Topsoil (to 0.25m), Light Brown Clay (to 0.9m), Light Grey Clay with Organics (to 1m), Black Organic soil (to 2.1m), Grey Orange Silty Gravel to depth
M35/11683 400m South 1.4 Dark Brown Topsoil (to 0.2m), Light Brown Clay (to 1.15m), Black Organic soil/peat (to 1.3m), Light Brown Silty Gravels to depth
M35/11684 460m South 1.4 Dark Brown Topsoil (to 0.22m), Light Brown Clay (to 1.09m), Black Organic soil/peat (to 1.35m), Light Brown Silty Gravels to depth
M35/11690 320m South 2.6
Dark Brown Topsoil (to 0.05m), Light Brown Clay (to 1.15m), Black Organic soil/peat (to 1.8m), Bluish Grey Clay (to 2.1m), Light Brown Sand (to 2.5m), Light Brown Silty Gravels to depth
M35/11691 300m South 2.9
Dark Brown Topsoil (to 0.2m), Light Brown Clay (to 1.25m), Black Organic soil/peat (to 1.65m), Bluish Grey Clay with Organics (to 2.4m), Light Brown Silty Sand (to 2.8m), Light Brown Silty Gravels to depth
The borehole logs are reasonably consistent with the soil profile identified in the investigation logs, with silt, peat and clayey material forming the upper soil layers and gravel at depths ranging from 1.5m bgl in the south of the site, deepening 4.0m to 5.0m to the north of the site. 4.5 Groundwater Levels
Groundwater levels and groundwater seepages were measured in the test pits. A summary of the groundwater measurements is provided in Table 2.
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Table 3– Measured groundwater levels
Test Pit
Groundwater Level (m)
Groundwater Seepage (m)
Test Pit
Groundwater Level (m)
Groundwater Seepage (m)
September 2011 Test pits TP15 4.2 2.6
TP1 3.1 1.1 TP16 3.6 1.6
TP2 2.3 Not Encountered TP17 3.0 Not Encountered
TP3 3.8 3.2 October 2007 Test pits
TP4 Not Encountered 2.0 TP1 2.4 Not Encountered
TP11 4.0 Not Encountered TP2 3.2 Not Encountered
TP13 Not Encountered 2.6 TP3 3.5 Not Encountered
TP14 2.1 Not Encountered TP5 4.0 Not Encountered
Note: Test pits not included where no groundwater level or seepage encountered These results appear to be in reasonable agreement with the groundwater levels identified in the ECan boreholes. We note that groundwater levels may vary depending on the time of year and climatic events. Groundwater in TP4 and TP13 was not reached as the digger was unable to excavate any further. It is assumed that the groundwater level in TP4 is not much further below the gravels as they are saturated. In TP13 the gravels were not reached and it is assumed that the gravels and groundwater are situated below the peat layer. 4.6 Site Walkover
4.6.1 Liquefaction Induced Ground Damage
Based on our site walkover the following was noted:
• Evidence of liquefaction surface ejecta (i.e. sand boils) was not apparent during the site walkover. Including residual evidence, such as degraded sand boils or distinct mounds covered in recent grass growth. Nor was there any evidence of accumulation of sand and silt within the stream.
• Other evidence of ground damage such as ground cracking or lateral spreading adjacent to the stream were not apparent on the site.
4.6.2 Geomorphological Mapping
Based on our site walkover and review of the general landscape, the site can be defined into two distinct geomorphological zones. The zones are shown in Figure 2 in Appendix A and are as follows: Zone 1 – Low Lying Area The low lying area comprises small hollows and indentions in the ground where surface water collects. This low lying area is located in the southern end of the site, from the top of the stream down towards Northbrook Road. Water collects in this area after rainfall events with the formation of pools of standing water.
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Zone 2 – Pastoral Land Area The pastoral land area includes the rest of the site. The area is flat, grassed and relatively level throughout.
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5. Ground Model Based on the ground investigation the following schematic ground model has been defined for the site. Northern Area Table 4 – Ground profile of the northern end of sit e.
Depth to Top of Unit
(m)
Depth to Base of Unit
(m) Soil Unit
0 0.2 to 0.4 TOPSOIL
0.2 to 0.4 1.5 to 2.1 SILT, Stiff to very stiff
1.5 to 2.1 2.1 to 3.5 Sandy SILT and Silty SAND, Stiff to very stiff and medium dense.
2.1 to 3.5 Depth
Investigation Clayey SILT, Sandy SILT, Stiff to very stiff
Middle Area Table 5 – Ground model of the middle section of sit e
Depth to Top of Unit
(m)
Depth to Base of Unit
(m) Soil Unit
0 0.3 to 0.4 TOPSOIL
0.1 to 0.2 2.0 to 2.7 SILT, Stiff to very stiff
2.0 to 2.7 2.9 to 4.6 PEAT, Soft to firm
2.9 to 4.6 3.5 to 4.6 Clayey Silt, Silty SAND and Sandy SILT, Firm to stiff
3.5 to 4.6 Depth
Investigation Sandy GRAVEL, medium dense to very dense
Southern Area Table 6 – Ground model of southern end of site
Depth to Top of Unit
(m)
Depth to Base of Unit
(m) Soil Unit
0 0.2 to 0.3 TOPSOIL
0.2 to 0.3 1.0 to 1.6 SILT, Stiff to very stiff
1.0 to 1.6 1.2 to 4.0 PEAT, Soft to firm
1.2 to 4.0 2.6 to 4.2 Clayey Silt and Sandy SILT, Firm to stiff
2.6 to 4.2 Depth
Investigation Sandy GRAVEL, Medium dense to very dense
The approximate extent of these areas is defined in Figure 2 in Appendix A. Using the CPT and test pit information we were able to construct three north-south cross sections displaying the bands of peat across the site, refer to Figures 8 to 10 in Appendix A.
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6. Engineering Consideration 6.1 General
VB Properties Limited is proposing to develop a residential subdivision on an area of vacant land on Northbrook Road. The subdivision site comprises a total area of approximately 20ha. Based on the ground conditions encountered during the geotechnical investigation we consider that the following geotechnical aspects need to be considered as part of the subdivision:
• Potential for seismically induced liquefaction. • Recommendations for liquefaction mitigation measures, if required. • Recommendation for peat soils. • Compliance with the intent and definition of NZS3604. • Implications for building foundations. • Recommendations for infrastructure construction. • Assessment against Resource Management Act (RMA) Section 106 a) to c).
Each of these is discussed in the following sections. 6.2 Seismically Induced Liquefaction
Under cyclic loading during an earthquake cohesionless material (gravels, sands, silty-sands) tends to decrease in volume. This tendency to decrease in volume is much greater in loose than dense soils. When cohesionless soils are saturated and rapid loading occurs under undrained conditions, the tendency is that soil densification causes excess pore water pressures to increase. The increase in pore water pressure results in a loss of soil strength due to a decrease in effective stress and eventually liquefaction when the effective stress drops to zero. Liquefaction of loose sands can lead to large displacements of foundations, ground surface settlement, sand boils, and post earthquake stability failures.
As part of our geotechnical assessment for the site we have carried out a liquefaction analysis to determine the liquefaction potential for the site.
6.3 Liquefaction Assessment
6.3.1 Introduction
For the site development the main factors to be considered for liquefaction are:
• What layers can liquefy?
• What is the likelihood of further liquefaction in the future?
• What options are available to limit or prevent liquefaction?
Each of these is considered below. 6.3.2 Liquefaction Potential Assessment
The three primary factors that contribute to liquefaction potential are:
• Loose, uniformly graded soils.
• High groundwater table.
• Sufficiently high, earthquake induced ground acceleration and sustained shaking.
Each of these is considered below together with conclusions on the site liquefaction potential.
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Soil Grading and Density
Based on our assessment of the soil conditions at the Northbrook site, the potential for liquefaction to occur is low. The reason for this is that the upper soil layers consist of very stiff silt with sandy gravels at depth. Groundwater
The depth to groundwater was measured in a number of the test pits at depths ranging from 2.1m to 4.2m bgl, with groundwater seepages measured at depths of 1.1m to 3.2m bgl. Soils are therefore potentially liquefiable from a depth of 1.1m onwards. Earthquake Intensity and Soil Resistance to Liquefa ction
The level of ground shaking is one of the key factors in determining whether liquefaction will or will not occur. A back analysis of the 4 September 2010 Darfield earthquake and 22 February 2011 Christchurch Earthquake has not been carried out as the nearest seismogram is located at the Ashley School, which is 5km to the North. Based on the potential variability of spatial and temporal variation from the earthquake centre and uncertainties and conservatisms associated with current analytical tools, it is considered that a back analysis of the recent earthquakes may not be accurate or representative. Therefore we have based the liquefaction analysis on Ultimate Limit State (ULS) and Serviceability Limit State (SLS) earthquake events derived using the NZGS method that in turn is based on NZS1170. This approach is generally accepted as a suitable method for liquefaction analysis as it ties into the building structural design criteria. We are aware that new seismic design guidelines for the Canterbury area are being developed by DBH and GNS, with the timing of their publication unknown at this stage. According to the ‘Minimum Requirements for Geotechnical Assessment of Liquefaction for Land Development – Canterbury Region’, these are likely to supersede the above guidelines for liquefaction analysis. However, in the absence of any updated guidelines and timeframes on when these will be published, it is considered appropriate to use the currently available guidelines. Therefore, based on the current guidelines available at the time of our analysis, we have used the following scenarios to assess the potential for liquefaction in a future seismic event: Serviceability Limit Stage (SLS) Earthquake
We have assessed the SLS earthquake return period based on the current NZS1170.0:2004 Loading Codes with the increased Z hazard factor of 0.3. NZS1170.0:2004 Table 3.3 indicates that SLS level ground shaking be based on a 1 in 33 year event. However, we consider this value to be too low to be applicable when assessing liquefaction because of its discreet nature of liquefaction (i.e. the site either liquefies or does not and when a site has liquefied there is very little difference in expected deformations for a ‘small’ earthquake that causes liquefaction relative to a ‘large’ earthquake that causes liquefaction), and the disproportionate effect seismically induced liquefaction has on a building. We have therefore adopted a more severe (although not unrealistic) earthquake event that has a probabilistic return period of 150 years. We have adopted the method outlined by the NZ Geotechnical Society with reference to the New Zealand Loadings Standard, to obtain the design earthquake for the liquefaction assessment. A 1 in 150 year return period earthquake in Lincoln area for a Class D site has a Peak Ground Acceleration (PGA) of 0.2g. In accordance with NZGS we have adopted a Magnitude 7.5 earthquake event. We consider this event to be well above the requirements from NZS1170 for SLS criteria, but believe it is realistic.
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Ultimate Limit State (ULS) Earthquake
For the site we have assessed the ULS earthquake return period based on the current NZS1170.0:2004 Loading Codes with the increased Z hazard factor of 0.3. A 500 year return period earthquake has been adopted, which is based on the recommendations of NZS1170.0:2004 Tables 3.2 (Importance Level 2 building), and Table 3.3 (50 year design working life). We have adopted the method outlined by the NZ Geotechnical Society for using the New Zealand Loadings Standard to obtain the design earthquake for the liquefaction assessment. A 1 in 500 year return period earthquake in the area for a Class D soil (Deep Soil Site) has a PGA of 0.34g, and in accordance with NZGS we have adopted a Magnitude 7.5 earthquake event. A summary of the shaking intensities is presented in Table 6.
Table 7 – Summary of ground shaking cases analysed
Earthquake PGA Magnitude Serviceability Limit State – Based on
NZS1170 0.20g 7.5
Ultimate Limit State – Based on NZS1170
0.34g 7.5
6.3.3 Liquefaction Analysis Results
The ability of the subsoils to resist the effects of ground shaking associated with the five earthquakes has been assessed from the information obtained from the CPT’s. The National Centre for Earthquake Engineering Research (NCEER) method as outlined by Youd et. al. (2001) has been used to assess liquefaction potential using Version 5 of the CivilTech Corporation LiquefyPro computer programme. The method of Robertson and Wride (1998) for the CPT boreholes (the NCEER’s recommended method), modified for fines content, was used to calculate the potential for liquefaction and the method of Tokimatsu and Seed (1987) for settlement. The total settlements due to liquefaction as calculated using the Tokimatsu and Seed (1987) method are presented below. The results show an average settlement for an SLS event of 0mm and 5mm for a ULS event (rounded to the nearest 5mm). Therefore, based on this evidence we have assessed the potential for liquefaction induced settlement as very low. The exception is CPT16 located in the north eastern corner of the site, where the potential total settlement calculated for a ULS event is 15mm.
Table 8 – Calculated liquefaction induced (total) s ettlement in (mm)
Test / CPT
SLS 1170 EQ
Settlement
(mm)
ULS 1170 EQ
Settlement
(mm)
1 0 0
2 0 0
3* 0 0
4* 0 0
5 0 0
6 0 0
7* 0 5
8 0 0
9* 0 10
10 0 0
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11* 0 0
12* 0 5
13* 0 0
14* 0 0
15* 0 0
16* 0 15
Min 0 0
Ave 0 2
Max 0 15
Note: The settlements presented in Table 7 above are to the nearest 5mm and have a likely error of ± 50% *- CPT tests that extended to a reasonable depth to accurately quantify the liquefaction risk over the site.
We note that due to the dense nature of the sandy gravel at depth none of the CPT’s extended to depths in excess of 10m bgl. However, we consider that these tests provided a reasonable coverage of the site and hence provide a good indication of the liquefaction risk across the site. 6.3.4 Ground Damage
Published information (after Ishihara, 1985) can be used to assess the potential for surface expression of liquefaction and the likelihood of ground induced damage. Our assessment of liquefaction induced ground damage, such as sand boils and ground cracking, showed that there is a very low potential for surface expression of liquefaction to occur on the site. The potential for surface expression of liquefaction is shown below.
Table 9 – Liquefaction induced ground damage for design eart hquakes.
Damaging Surface Expression
Test / CPT SLS 1170 EQ ULS 1170 EQ
1 N N
2 N N
3 N N
4 N N
5 N N
6 N N
7 N N
8 N N
9 N N
10 N N
11 N N
12 N N
13 N N
14 N N
15 N N
16 N N
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6.3.5 Lateral Spreading
Liquefaction induced lateral spreading or flow failures can occur when the shear stresses required to maintain static equilibrium are greater than the shear strength of the liquefied soil. Structures built on ground that experiences lateral spreading can be expected to sustain significant damage relative to the damage that would be expected from ground shaking alone. The watercourse on the site is relatively shallow (i.e. less than 1.0m deep) and the ground water levels are at depths greater than 1m. Therefore, the proposed stormwater drains and existing drains are unlikely to pose a lateral spreading risk to the development. Based on this evidence we have assessed the potential for lateral spreading as very low. 6.3.6 Discussion
• Under a SLS earthquake case, the total settlements are typically 0mm and there is unlikely to be any liquefaction induced ground damage.
• Under a ULS earthquake case the total settlements are typically less than 5mm. The exception is CPT16, where potential total settlement is in the order of 15mm. Based on the results there is a very low potential for liquefaction induced ground damage. It is, however, noted that during the ULS design earthquake some building damage is likely at this level of shaking regardless of ground conditions and liquefaction potential.
• The calculated settlements across the site are reasonable consistent, especially for the CPT’s which extended to depths ranging from 2.98m to 8.38m bgl. This would indicate that the potential liquefaction induced settlements across the site are likely to be consistent. The exception is CPT16 in the north eastern corner of the site. Based on our ground investigations we infer that this is due to the ground conditions at this location.
6.4 Land Classification Technical Categories
For the Christchurch region the DBH has recently released a new classification system for residential ‘Green Zone’ land on the flat in respect of liquefaction susceptibility. This new classification system is divided into three technical categories that reflect both the liquefaction experience to date and future performance expectations. The categories and corresponding criteria are summarised as follows:
• Technical Category 1 (TC1) – future land damage from liquefaction is unlikely, and ground settlements are expected to be within normally accepted tolerances.
• Technical Category 2 (TC2) – Minor to moderate land damage from liquefaction is possible in future large earthquakes.
• Technical Category 3 (TC3) – Moderate to significant land damage from liquefaction is possible in future large earthquakes.
The DBH has indicated the following liquefaction deformation limits for house foundations as summarised in Table 9 below:
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Table 10 – Liquefaction deformation limits and hous e foundation implications
Technical Category
Liquefaction Deformation Limits Likely Implication for House Foundations (subject to individual assessment)
Vertical Lateral Spread SLS ULS SLS ULS
TC1 15mm 25mm Nil Nil Standard NZS3604 type foundations with tied slabs
TC2 50mm 100mm 50mm 100mm DBH enhanced foundation solutions
TC3 >50mm >100mm >50mm >100mm Site specific foundation solution
Based upon results of the liquefaction assessment described in Section 6.3 the potential for liquefaction is very low and as such the site can be placed within the TC1 category. However, this is relates only to liquefaction and not the presence of peat and other organic soils which may give rise to excessive total and differential settlement.
6.5 Compliance with the Definition of ‘Good Ground’
Based on the findings of this geotechnical assessment it is inferred that the site is non-compliant with the intent of the definition of ‘Good Ground’ in terms of the New Zealand Standards Timber Framed Buildings (NZS3604:2011) and Concrete Masonry Buildings Not Requiring Specific Engineering Design (NZS4229:1999), from an available soil bearing capacity aspect. Therefore, irrespective of any potential liquefaction risk at the site typical light weight timber framed or masonry houses (which would generally be designed within the guidelines of NZS3604:2011 or NZS4229:1999) would require specific foundation design. 6.6 Peat
The ground investigation identified peat layers predominately within the southern and middle areas of the site at between 1.0m and 4.6m bgl. The southern area of the site shows peat layers within the top 4.4m.The peat layers are between 0.8m and 2.4m thick. The middle area exhibited thickness of 1.0m to 2.3m of peat. Thin peat layers were identified in the northern area of the site but were typically less than 0.5m thick and present at depths ranging from 2.5m to 5.5m bgl. Given that peat does not liquefy, the main concern with the peat layer is in terms of foundations for buildings and infrastructure. 6.6.1 Infrastructure
On the assumption that the majority of the infrastructure is placed within the sand and silt deposits overlying the thick peat deposit, no special pre earthworks are required to protect the infrastructure, subject however to confirmation of the infrastructure design and loadings. It is anticipated that further assessment of infrastructure will be required at the detailed design stage. For deep and/or heavy infrastructure pile foundations as per the main site may be required. 6.6.2 Residential Foundations
Due to the residential nature of the development and the presence of thick deposits of peat, future residential development will require foundations to limit consolidation and creep settlement in the peat. Piles are therefore recommended and founded in the basal sandy gravels typically at 2.0m to 4.6m bgl. Pile foundations will transfer structural loads from the structure to deeper and stronger non-liquefiable sandy gravel layers at 2.0m to 4.6m bgl, thereby minimising any structural damage associated with the ground due to the presence of peat.
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Piled foundations for a residential house typically comprise driven piles and can be either concrete (typically used if a concrete floor system is to be used), or timber (typically used if a timber floor and sub-floor system is to be used). A pile foundation system does not require any special soil preparation, but will require site specific investigation and design. We note that all pile foundations are to be designed to carry the full structural loads and stresses with no reliance on the ground below the slab. As required under the new DBH guidelines, a building consent investigation will be required for each lot. 6.6.3 Discussion and Recommendations
The DBH advised the above foundation systems for residential houses built in areas potentially susceptible to seismically induced liquefaction or settlement. Guidance and typical design details are provided in their publication ‘Guidance on house repairs and reconstruction following the Canterbury Earthquake’, dated 20 December 2010. It is typically recommended that piled foundation s are adopted for residential housing at sites where thick deposits of peat are present at shallow depths. If the pile foundation option is adopted, then the floor slab should be well reinforced to provide continuity across the building floor and foundation elements. The objective will be to provide additional capacity in the floor slab and enhance its ability to redistribute loads. All pile heads need to be adequately tied into the floor slab. As part of the detailed house foundation design, particular attention should be paid to detailing the connection joints of buried services (water and sewer pipes, power conduits, etc.) between the house foundation and the in situ ground. The design should allow sufficient movement and ductility to account for seismic shaking and movement, and to allow for the easy reinstatement if they were to be damaged during a future seismic event. It should be noted that the above discussion on the foundation options is generic only. The actual foundation option chosen and associated costs will depend upon the specific design of the proposed dwelling and the results of a site specific geotechnical and structural assessments. 6.6.4 Proposed Earthworks
It is likely that the amount of earthworks required for the site will be minimal as the site is relatively flat with a very low risk of liquefaction occurring. Although there are layers of peat present throughout the site, due to the depth of peat layers it would be both time consuming and costly to remove the peat as part of any preparatory earthworks. 6.7 General Site Development Recommendations
6.7.1 Cut Excavations
Based on the investigation results we make the following comments:
• Cuts are likely to encounter predominantly silty soil with the potential for sand layers. We anticipate that the soils will be easy to excavate with conventional earth moving equipment.
• Cuts greater than 1.5m in height should be inspected by a geotechnical engineer or
engineering geologist as work proceeds to confirm the acceptability of the actual slopes;
• Cut slopes of 3H:1V are likely to maintain global stability for static and seismic cases.
• Groundwater seepages maybe encountered in cut excavations. If significant groundwater inflows are encountered and left untreated, slumping of cuts could occur. If groundwater
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seepages are encountered these should be inspected by a geotechnical engineer or engineering geologist and site specific treatment adopted, as required.
• Cut slopes will be vulnerable to erosion and therefore should be hydroseeded/planted or
otherwise protected as soon as practicable after excavation. 6.7.2 Earthfill
We make the following recommendations with regard to the fill placement: • Filling shall generally be carried out in accordance with NZS4431:1989 – Code of Practice for
Earth Fill for Residential Development, with appropriate on site quality control;
• Depending on the nature of the fill material the appropriate compaction standard will need to be applied. A geotechnical engineer should review the compaction standard prior to site earthworks.
• All areas where earthfill is to be placed should be stripped of topsoil and other organic material
and stockpiled.
• Benching to key the fills into the ground is required wherever the existing ground slope is steeper than 3H:1V.
• Fill slopes are likely to be stable at a slope of 3H:1V. If fill slopes are required to be steeper,
then the use of geogrids may be required to reinforce the fill edge. This should be assessed by a geotechnical engineer as part of the detail design.
• The fill slope could be vulnerable to erosion if concentrated stormwater flows develop. To
control runoff from the fill batters and scouring of the fill, the front face should be planted and stormwater runoff directed away from the fill face.
• The design of any fill slope will need to take into account the potential for liquefiable soils or the presence of peat at the base of the slope.
• If fill depths exceed 0.5m, we recommend a geotechnical engineer carries out an assessment to confirm the affect the fill surcharge will have on the peat.
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7. Assessment Against RMA Section 106 of the Resource Management Act (RMA) states inter alia
… “a consent authority may refuse to grant a subdivision consent, or may grant a subdivision consent subject to conditions, if it considers that:
a) the land in respect of which a consent is sought, or any structure on the land, is or is likely to be subject to material damage by erosion, falling debris, subsidence, slippage, or inundation from any source; or
b) any subsequent use that is likely to be made of the land is likely to accelerate, worsen, or result in material damage to the land, other land, or structure by erosion, falling debris, subsidence, slippage, or inundation from any source; or
c) sufficient provision has not been made for legal and physical access to each allotment to be created by the subdivision.”
No erosion was observed on the site. However the silty soils that directly underlie parts of the site are inferred to be potentially susceptible to erosion when the site is left without vegetation cover. We infer that the site is not susceptible to falling debris or slippage due to the topographical location. It is noted that issues surround stormwater discharge are being dealt with in the detailed civil engineering design. Therefore any potential “inundation” susceptibility due to stormwater has already been addressed. Due to the presence of peaty and organic soils at depth we infer that the site is possibly susceptible to subsidence. However, if the appropriate peaty soil mitigation measures, as outlined in this report, are undertaken then the risk of subsidence is significantly addressed. Therefore, with appropriate mitigation measures where required, the site in our opinion will generally be free of “erosion”, “falling debris”, “subsidence”, “slippage”, or “inundation”. The proposed subdivision development therefore generally complies with the intent of Section 106 (a). Due to the site being partially underlain by fine grained soils, there exists the potential for erosion and drilling of the sandy and silty soils if vegetation cover is removed for prolonged periods of time from both stormwater runoff if it is not discharged in a controlled manner, and from the wind. This susceptibility to erosion of the sandy and silty soils can be minimised with appropriate industry standard design measures undertaken during construction. Revegetation should be carried out as soon as practicable post bulk earthworks. The site has been identified as being partially susceptible to consolidation or settlement and hence has the potential for “subsidence. Provided that appropriate consolidation mitigation measures are implemented, as recommended in this report, subsequent use of the land following development is unlikely to accelerate, worsen, or result in material damage to the land, other land, or structures. In our opinion therefore, the development will comply with the intent of Section 106 (b). Section 106 (c) is not directly relevant to a geotechnical appraisal and therefore has not been considered in detail in this report, although it is noted that the site is accessible from Northbrook Road. Thus in our opinion, under Section 106 of the RMA, there are no geotechnical reasons preventing the development, provided the appropriate engineering measures as recommended in this report are carried out.
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8. References Brown and Weeber, (compliers), 1992. Geology of the Christchurch urban area. Institute of Geological and Nuclear Sciences, 1:25,000 geological map 1. 1 sheet + 104p. Lower Hutt, New Zealand.
Department of Building and Housing, 2011. Compliance Document for New Zealand Building Code, Clause B1, Structures.
Department of Building and Housing, 2011. Interim Minimum Requirements for Geotechnical Assessment of Liquefaction for Land Development – Canterbury Region
Department of Building and Housing, 2011. ‘Guidance on house repairs and reconstruction following the Canterbury Earthquake’, dated 20 December 2010 – Canterbury Region
Geonet, 2011. ftp://ftp.geonet.org.nz/strong/processed/Proc
Gerstenberger, M.; Cubrinovski, M; McVerry, G.; Stirling, M.; Rhoades, D.;Bradley, B.; Langridge, R.; Webb, T.; Peng, B.; Pettinga, J.; Berryman, K.; Brackley, H. 2011. Probabilistic assessment of liquefaction potential for Christchurch in the next 50 years, GNS Science Report 2011/15 30 p.
GNS, 1999. Probabilistic Seismic Hazard Assessment and Earthquake Scenarios for the Canterbury Region, and Historic Earthquakes in Christchurch. Geological and Nuclear Sciences, Lower Hutt, Wellington.
GNS, 2011a. http://maps.gns.cri.nz/website/af/viewer.htm
GNS, 2011b. http://www.gns.cri.nz/Home/News-and-Events/Media-Releases/earthquake-part-of-aftershock-sequence
Ishihara, 1985. Stability of natural deposits during earthquakes. Proceedings, 11th International Conference on soil Mechanics and Foundation engineering, Vol 1, 321-376.
Ishihara and Yoshimine, 1992. Evaluation of settlements in sand deposits following liquefaction during earthquakes. Soils and Foundations, Vol. 32, No. 1, pp. 173-188.
Kramer, 1996. Geotechnical Earthquake Engineering. Prentice Hall, Upper Saddle River, NJ, USA.
Martin, G. and Lew, M., 1999. Recommended Procedure for Implemention of DMG Special Publication 117 – Guidelines for Analyzing and Mitigating Liquefaction in California. Southern California Earthquake Center, University of Southern California. Ca, USA.
NZS1170.0:2002. Australia/New Zealand Standard, Structural Design Actions, Part 0: General Principals. Standards New Zealand, Wellington, New Zealand.
NZS1170.5:2002. Australia/New Zealand Standard, Structural Design Actions, Part 5: Earthquake Actions – New Zealand. Standards New Zealand, Wellington, New Zealand.
NZGS, 2005. Guidelines for the Classification and Field Description of Soils and Rocks in Engineering. NZ Geotechnical Society Inc, Wellington, New Zealand.
NZGS, 2010. Geotechnical earthquake engineering practice, Module 1 – Guideline for the identification, assessment and mitigation of liquefaction hazards. NZ Geotechnical Society Inc, Wellington, New Zealand.
Robertson and Wride, 1998. Evaluating cyclic liquefaction potential using the cone penetration test. Canadian Geotechnical Journal, Vol. 35, pp. 442 – 459.
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Sewell, R. J.; Weaver, S. D.; Reay, M. B. (1992) ‘Geology of the Banks Peninsular - Scale 1:100,000’. Institute of Geology & Nuclear Sciences Geological Map 3, Institute of Geological and Nuclear Sciences Ltd, Lower Hutt, New Zealand.
Structural Engineering Society (SESOC), 2011. Christchurch Seismic Design Load Levels Interim Advice.
Tonkin & Taylor, 2010 Darfield Earthquake 4 September 2010 Geotechnical Land Damage Assessment and Reinstatement Report; Stage 1 Report, for the Earthquake Commission.
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9. Limitations We have prepared this report in accordance with the brief as provided. The contents of the report are for the sole use of the Client and the Waimakariri District Council for the purpose of subdivision consent only, and no responsibility or liability will be accepted to any other third party. Data or opinions contained within the report may not be used in other contexts or for any other purposes without our prior review and agreement.
The recommendations in this report are based on data collected at specific locations and by using suitable investigation techniques with limited site coverage. Only a finite amount of information has been collected to meet the specific financial and technical requirements of the Client’s brief and this report does not purport to completely describe all the site characteristics and properties. The nature and continuity of the ground and groundwater between test locations has been inferred using experience and judgment and it must be appreciated that actual conditions could vary from the assumed model.
Subsurface conditions relevant to construction works should be assessed by contractors who can make their own interpretation of the factual data provided. They should perform any additional tests as necessary for their own purposes.
Subsurface conditions, such as groundwater levels, can change over time. This should be borne in mind, particularly if the report is used after a protracted delay.
We note that resource and building consents are required from local and regional authorities in advance to develop the proposed subdivision. The application of all consents is the responsibility of the client; however Aurecon can assist if required.
This report is not to be reproduced either wholly or in part without our prior written permission.
Appendix A Figures
Aurecon New Zealand Limited
Unit 1, 150 Cavendish Road
Casebrook
PO Box 1061
Christchurch - New Zealand
Client
Project
By
Figure 1
Date Job Number
A4
Paper Size
Revision
Note: Not to scale; boundaries and locations are approximate only
1
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Email: christchurch@ap.aurecongroup.com
Website: www.aurecongroup.com
VB Properties 2008 Limited
MHD 23 November2011 223094
Northbrook Subdivision
Site Location
N
Site Location
Northbrook Road
Rangiora
Aurecon New Zealand Limited
Unit 1, 150 Cavendish Road
Casebrook
PO Box 1061
Christchurch - New Zealand
Client
Project
By
Figure 2
Date Job Number
A4
Paper Size
Revision
Note: Not to scale; boundaries and locations are approximate only
1
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Email: christchurch@ap.aurecongroup.com
Website: www.aurecongroup.com
VB Properties 2008 Limited
MHD 23 November2011 223094
Northbrook Subdivision
Site Location and Geomorphological Features
N
Stream
Low Lying area – Zone 1
Power lines
Aurecon New Zealand Limited
Unit 1, 150 Cavendish Road
Casebrook
PO Box 1061
Christchurch - New Zealand
Client
Project
By
Figure 3
Date Job Number
A4
Paper Size
Revision
Note: Not to scale; boundaries and locations are approximate only
1
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Email: christchurch@ap.aurecongroup.com
Website: www.aurecongroup.com
VB Properties 2008 Limited
MHD 23 November2011 223094
Northbrook Subdivision
Geological Map of Canterbury Region
N
Site Location
Aurecon New Zealand Limited
Unit 1, 150 Cavendish Road
Casebrook
PO Box 1061
Christchurch - New Zealand
Client
Project
By
Figure 4
Date Job Number
A4
Paper Size
Revision
Note: Not to scale; boundaries and locations are approximate only
1
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Email: christchurch@ap.aurecongroup.com
Website: www.aurecongroup.com
VB Properties 2008 Limited
MHD 23 November2011 223094
Northbrook Subdivision
CPT Locations
16
15
3
7
8
9
10
11
13
12
14
1
2
4
5
6
Aurecon New Zealand Limited
Unit 1, 150 Cavendish Road
Casebrook
PO Box 1061
Christchurch - New Zealand
Client
Project
By
Figure 5
Date Job Number
A4
Paper Size
Revision
Note: Not to scale; boundaries and locations are approximate only
1
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Email: christchurch@ap.aurecongroup.com
Website: www.aurecongroup.com
VB Properties 2008 Limited
MHD 23 November2011 223094
Northbrook Subdivision
Test Pit Locations in 2011
N
TP1
TP9TP8
TP7TP6
TP5
TP4 TP3
TP2
TP16
TP17
TP15TP14
TP13TP12
TP11
TP10
Aurecon New Zealand Limited
Unit 1, 150 Cavendish Road
Casebrook
PO Box 1061
Christchurch - New Zealand
Client
Project
By
Figure 6
Date Job Number
A4
Paper Size
Revision
Note: Not to scale; boundaries and locations are approximate only
1
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Email: christchurch@ap.aurecongroup.com
Website: www.aurecongroup.com
VB Properties 2008 Limited
MHD 23 November2011 223094
Northbrook Subdivision
Test Pit Locations in 2006
N
TP2
TP1
TP3
TP8
TP7
TP6
TP4
TP5
Aurecon New Zealand Limited
Unit 1, 150 Cavendish Road
Casebrook
PO Box 1061
Christchurch - New Zealand
Client
Project
By
Figure 7
Date Job Number
A4
Paper Size
Revision
Note: Not to scale; boundaries and locations are approximate only
1
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Email: christchurch@ap.aurecongroup.com
Website: www.aurecongroup.com
VB Properties 2008 Limited
MHD 23 November2011 223094
Northbrook Subdivision
Environment Canterbury GIS Borehole Locations
N
M35/11683
M35/11559
M35/8026
M35/11684
Site Location
PEAT
PEAT
PEAT
PEAT
PEAT
??
SANDY GRAVEL
SANDY GRAVEL
TOPSOIL TOPSOIL TOPSOIL TOPSOIL TOPSOIL TOPSOILTOPSOIL
CLIENT
NORTHBROOK ROADRANGIORA
DATE
TITLE
REVISION DETAILSDATEREV APPROVED
CHECKED
APPROVED
PROJECTDRAWN DESIGNED
223094PROJECT No.
SCALE SIZE
DRAWING No. REV
A3GEOLOGICAL CROSS SECTIONSTP 2,3,4,5,6,7,8,9 Figure 8 A
AS SHOWN
NOT FOR CONSTRUCTIONT Stocker M Derkson
J Murison
M DohertyA 8-12-2011 ISSUED M Doherty
00/0
0/00
VB Properties 2008 Limited
TOPSOIL TOPSOIL TOPSOIL TOPSOIL TOPSOIL TOPSOIL
SANDY GRAVEL SANDY GRAVEL ???
??
PEAT
PEAT
PEAT
PEAT
PEAT
CLIENT
NORTHBROOK ROADRANGIORA
DATE
TITLE
REVISION DETAILSDATEREV APPROVED
CHECKED
APPROVED
PROJECTDRAWN DESIGNED
223094PROJECT No.
SCALE SIZE
DRAWING No. REV
A3GEOLOGICAL CROSS SECTIONSTP 10,11,12,13,14,15,16 Figure 9 A
AS SHOWN
NOT FOR CONSTRUCTIONT Stocker M Derkson
J Murison
M DohertyA 8-12-2011 ISSUED M Doherty
00/0
0/00
PEAT
PEAT
PEAT
PEAT
PEAT
SILTSILT
SILT
SILT
SILT
SANDY GRAVEL
SANDY GRAVEL
SANDY GRAVELSANDY GRAVEL
Appendix B CPT Logs
CPT ANALYSIS NOTES
Soil Type Interpretation using chart of Robertson & Campanella (1983). This is a simple but well proven interpretation using cone tip resistance (qC) and friction ratio (fR) only. No normalisation for overburden stress is applied. Cone tip resistance measured with the piezocone is corrected with measured pore pressure (uC).
sand (and gravel)
silt-sand
silt
clay-silt
clay
peat
Liquefaction Screening The purpose of the screening is to highlight susceptible soils, that is sand and silt-sand in a relatively loose condition. This is not a full liquefaction risk assessment which requires knowledge of the particular earthquake risk at a site and additional analysis. The screening is based on the chart of Shibata and Teparaksa (1988).
high susceptibility
medium susceptibility
low susceptibility
High susceptibility is here defined as requiring a shear stress ratio of 0.2 to cause liquefaction with D50 for sands assumed to be 0.25 mm and for silty sands to be 0.05 mm.
Medium susceptibility is here defined as requiring a shear stress ratio of 0.4 to cause liquefaction with D50 for sands assumed to be 0.25 mm and for silty sands to be 0.05 mm.
Low susceptibility is all other cases.
Relative Density (DR) Based on the method of Baldi et. al. (1986) from data on normally consolidated sand.
Undrained Shear Strength (SU)
Derived from the bearing capacity equation using SU = (qC –σVO)/15.
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT001
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT002
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT003
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT004
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT005
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT006
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT007
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT008
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT009
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT010
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT011
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT012
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT013
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT014
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT015
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT
qc (MPa) Type Liq Dr (%) Su (KPa)
Job No:
CPT No:
Project:
Location:
Date:
Operator:
Remark:
9552
CPT016
Aurecon
Northbrook Subdivision, Rangiora
28/10/2011
J. Kendrick
Effective Refusal
0 10 20 30 40 50
0510
0
2
4
6
8
10
Friction Ratio (%)
0 20 40 60 80 0 40 80 120 160 200
CIVIL CONSTRUCTION OVERVIEW 5 x Piling Rigs (20 to 80 tonne); 4 x Tieback/Micro-Piling Rigs (0.5 to 20 tonne); Sheet Piling & Injection Grouting; Dewatering; 26 x Drilling Rigs Company wide.
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Can be used next to sensitive buildings; No mess (dry); Cost effective (minimal setup times); Further savings possible for building construction – i.e.
ground beams, deep rafts, pile starters, boxing to piles; No corrosion issues, all natural materials; Reliance on individual piles, and the risk of differential
settlement is reduced.
Fully Instrumented Continuous Flight Auger / Displacement Auger Piling:
Cost effective; Sizes 350mm to 900mm and 19m depth; Fast (150m of 600mm diameter reinforced concrete pile can
be installed per day); Lateral load capacity of RC piles exceed some other piling
methods; Quiet & vibration free; Fully reinforced concrete piles, with no corrosion issues.
McMILLAN’S ALSO OFFER THE FOLLOWING SERVICES: Screw Piles; Conventional Bored Concrete Piles; Mini & Micro Piles; Retaining Walls; Sheet Piling; Anchors & Tiebacks.
Please contact us to find out more information or visit our website www.drilling.co.nz
Geotechnical Assessment Report
Project 223094 | File 223094 Geotech Report Rev1 Second Issue.docx 20 December 2011 | Revision 1 Aurecon Page i
Appendix C Test Pit Logs
0.30
1.00
1.20
3.00
3.10
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Low plasticity.Friable.
SILT; Light yellow grey with orange brown mottling. Stiff. Moist. Low plasticity.Friable.
PEAT with some tree branches and minor silt; Dark brown. Firm. Saturated.Low plasticity. Organic. Fibrous.
Clayey SILT; Light blue grey. Stiff. Saturated. High plasticity.
Sandy GRAVEL; Light brown yellow. Medium dense. Saturated. Gravel fine tocoarse grained and sub rounded. Sand coarse grained.
End of Test Pit at 3.1m (GW reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:1
6 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
Groundwater encountered @ 1.1mGroundwater encountered @ 3.1m
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1568145 mNorthing: 5204745 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP01
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.30
1.40
2.30
2.60
3.10
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Low plasticity.Friable.
SILT; Light yellow grey with orange brown mottling. Very stiff. Dry to moist.Low plasticity. Friable.
PEAT with some tree branches and minor silt; Dark brown. Firm. Saturated.Low plasticity. Organic. Fibrous.
Clayey SILT; Light blue grey. Stiff. Saturated. High plasticity.
Sandy GRAVEL; Light brown yellow. Medium dense. Saturated. Gravel fine tocoarse grained and sub rounded. Sand coarse grained.
End of Test Pit at 3.1m (GW reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:1
7 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
Groundwater encountered @ 2.3m
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1568027 mNorthing: 5204778 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP02
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.30
1.70
3.20
3.70
3.80
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Low plasticity.Friable.
SILT; Light yellow grey with orange brown mottling. Very stiff. Dry to moist.Low plasticity. Friable.
PEAT with some tree branches and minor silt; Dark brown. Firm. Saturated.Organic. Low plasticity. Fibrous.
Sandy SILT; Light blue grey with brown mottling. Stiff. Saturated. Lowplasticity. Sand fine grained.
Sandy GRAVEL; Light brown yellow. Medium dense. Saturated. Gravel fine tocoarse grained and sub rounded. Sand coarse grained.
End of Test Pit at 3.8m (GW reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:1
7 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
Groundwater seepage @ 3.2mGroundwater encountered @ 3.8m
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1568005 mNorthing: 5204915 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP03
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.30
2.00
3.00
3.50
4.00
4.10
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Low plasticity.Friable.
SILT; Light yellow grey with orange brown mottling. Very stiff. Dry to moist.Low plasticity. Friable.
PEAT with some tree banches and minor silt; Dark brown. Firm. Saturated.Organic. Low plasticity. Fibrous.
Clayey SILT; Light blue grey. Stiff. Saturated. High plasticity.
Silty SAND; Light blue grey with brown mottling. Stiff. Saturated. Sand finegrained.
Sandy GRAVEL; Light brown yellow. Medium dense. Saturated. Gravel fine tocoarse grained and sub rounded. Sand coarse grained.
End of Test Pit at 4.1m (Required depth reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:1
8 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
Groundwater seppage @ 2.0m
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1568002 mNorthing: 5205002 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP04
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.30
2.20
3.10
4.60
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Low plasticity.Friable.
SILT; Light yellow grey with orange brown mottling. Very stiff. Dry to moist.Low plasticity. Friable.
SILT; Light grey with orange brown mottling. Very stiff. Moist. Low plasticity.Friable.
PEAT with some silt and tree matter; Light grey brown. Stiff. Wet to saturated.High plasticity.
End of Test Pit at 4.6m (Required depth reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:1
9 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
No groundwater encounteredTree root/branch encountered @ 3.1m
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1567915 mNorthing: 5205102 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP05
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.30
2.70
2.90
4.50
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Friable. Lowplasticity.
SILT; Light yellow grey with orange brown mottling. Very stiff. Dry to moist.Low plasticity. Friable.
PEAT with some tree branches; Light grey brown. Firm. Moist. Low plasticity.Fibrous.
Clayey SILT with minor sand and tree branches; Light blue grey. Stiff. Moist.High plasticity. Sand is fine grained.
End of Test Pit at 4.5m (Required depth reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:1
9 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
No groundwater encounteredTree branch encountered @ 2.7mTree branch encountered @ 4.0m
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1567958 mNorthing: 5205179 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP06
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.40
1.50
1.90
3.50
4.50
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Friable. Lowplasticity.
SILT; Light yellow grey with orange brown mottling. Very stiff. Dry to moist.Low plasticity. Friable.
Silty SAND; Light yellow brown with orange brown mottling. Medium dense.Moist. Sand fine to medium grained.
Sandy SILT with some tree matter; Light blue grey. Very Stiff. Moist. Lowplasticity. Sand is fine grained.
Clayey SILT with minor sand; Light blue grey. Stiff. Moist to wet. Highplasticity. Sand is fine grained.
End of Test Pit at 4.5m (Required depth reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:2
0 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
No groundwater encounteredTree branches and roots from 2.2m - 2.6m
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1567957 mNorthing: 5205275 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP07
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.30
2.10
2.40
2.60
4.40
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Friable. Lowplasticity.
SILT; Light yellow grey with orange brown mottling. Very stiff. Dry. Lowplasticity. Friable.
Sandy SILT; Light yellow brown. Stiff. Moist. Low plasticity. Sand fine tomedium grained.
Clayey SILT; Light blue grey. Stiff. Moist to wet. High plasticity.
Sandy SILT with some tree matter; Light blue grey. Very Stiff. Moist to wet.High plasticity. Sand is fine grained.
End of Test Pit at 4.4m (Required depth reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:2
0 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
No groundwater encountered
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1567930 mNorthing: 5205323 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP08
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.30
2.10
3.40
4.40
TOPSOIL gravelly with some rootlets; Dark brown. Loose. Dry. Friable. Gravelmedium grained and sub rounded.
SILT; Light yellow grey with orange brown mottling. Very stiff. Dry to moist.Low plasticity. Friable.
Sandy SILT; Light yellow brown. Stiff. Moist. Low plasticity. Sand fine tomedium grained.
Clayey SILT; Light blue grey with orange brown mottling. Stiff. Moist to wet.High plasticity.
End of Test Pit at 4.4m (Required depth reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:2
1 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
No groundwater encountered
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1567902 mNorthing: 5205418 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP09
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.40
1.50
3.10
4.20
4.40
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Friable. Lowplasticity.
SILT; Light yellow grey with orange brown mottling. Very stiff. Dry to moist.Low plasticity. Friable.
Sandy SILT; Light yellow brown. Stiff. Moist. Low plasticity. Sand fine tomedium grained.
Clayey SILT; Light blue grey with orange brown mottling. Stiff. Moist. Lowplasticity.
Sandy SILT; Light blue grey. Stiff. Moist. Low plasticity. Sand fine to mediumgrained.
End of Test Pit at 4.4m (Required depth reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:2
1 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
No groundwater encountered
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1568088 mNorthing: 5205467 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP10
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.20
1.60
2.10
2.60
4.00
4.10
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Friable. Lowplasticity.
SILT; Light yellow grey with orange brown mottling. Very stiff. Dry to moist.Low plasticity. Friable.
Sandy SILT; Light yellow brown. Stiff. Moist. Low plasticity. Sand fine tomedium grained.
Clayey SILT; Light blue grey with orange brown mottling. Stiff. Moist. Lowplasticity.
Sandy SILT; Light blue grey. Stiff. Moist. Low plasticity. Sand fine to mediumgrained.
Sandy GRAVEL; Light brown yellow. Medium dense. Saturated. Gravel fine tocoarse grained and sub rounded. Sand coarse grained.
End of Test Pit at 4.1m (GW reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:2
2 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
Groundwater encountered @ 4.0m
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1568082 mNorthing: 5205363 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP11
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.30
1.60
1.80
2.20
3.00
3.40
4.30
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Friable. Lowplasticity.
SILT; Light yellow grey with orange brown mottling. Very stiff. Dry to Moist.Low plasticity. Friable.
Sandy SILT; Light yellow brown with orange brown mottling. Stiff. Moist. Lowplasticity. Sand fine to medium grained.
Silty SAND; Orange brown. Medium dense. Moist. Sand fine to coarsegrained.
SILT; Light yellow grey with orange brown mottling. Stiff. Moist. Low plasticity.Friable.
Sandy SILT; Light yellow brown. Stiff. Moist. Low plasticity. Sand fine tomedium grained.
PEAT with some silt and minor tree branches; Light blue grey. Soft to firm.Wet. High plasticity.
End of Test Pit at 4.3m (Required depth reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:2
2 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
No groundwater encountered
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1568115 mNorthing: 5205239 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP12
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.40
2.00
2.60
4.50
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Low plasticity.Friable.
SILT; Light yellow grey with orange brown mottling. Very stiff. Dry to Moist.Low plasticity. Friable.
SILT; Light blue grey with orange brown mottling. Stiff. Moist to wet. Highplasticity.
PEAT with some silt and minor tree branches; Light blue grey. Stiff. Wet. Highplasticity.
End of Test Pit at 4.5m (Required depth reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:2
3 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
Groundwater seepage @ 2.6m
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1568151 mNorthing: 5205146 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP13
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.30
2.10
4.40
4.60
4.80
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Low plasticity.Friable.
SILT; Light grey with orange brown mottling. Stiff. Dry. Low plasticity. Friable.
PEAT with some silt and tree branches; Dark brown. Soft to firm. Saturated.Low plasticity.
Clayey SILT; Light blue grey with orange brown mottling. Stiff. Moist to wet.High plasticity.
Sandy SILT; Light blue grey. Stiff. Moist. Low plasticity. Sand fine to mediumgrained.
End of Test Pit at 4.8m (Required depth reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:2
3 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
Groundwater seepage @ 2.1m
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1568160 mNorthing: 5205033 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP14
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.30
1.60
4.00
4.20
4.40
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Low plasticity.Friable.
SILT; Light grey with orange brown mottling. Stiff. Dry. Low plasticity. Friable.
PEAT with some silt and tree branches; Dark brown. Soft to firm. Saturated.Low plasticity. Fibrous.
Sandy SILT; Light blue grey. Stiff. Moist. Low plasticity. Sand fine to mediumgrained.
Sandy GRAVEL; Light brown yellow. Medium dense. Saturated. Gravel fine tocoarse grained and sub rounded. Sand coarse grained.
End of Test Pit at 4.4m (GW reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:2
4 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
Tree branches @ 1.6mGroundwater seepage @ 2.6mGroundwater encountered @ 4.2
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1568172 mNorthing: 5204974 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP15
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.30
1.60
3.10
3.60
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Low plasticity.Friable.
SILT; Light grey with orange brown mottling. Stiff. Dry. Low plasticity. Friable.
PEAT with some silt and tree branches. Dark brown. Soft to firm. Saturated.Low plasticity. Fibrous.
Sandy GRAVEL; Light blue grey. Dense. Saturated. Gravel fine to coarsegrained and sub rounded. Sand coarse grained.
Sandy GRAVEL; Light yellow brown. Dense. Saturated. Gravel fine to coarsegrained and sub rounded. Sand coarse grained.
End of Test Pit at 3.6m (GW reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:2
4 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
Groundwater seepage @ 1.6mGroundwater encountered @ 3.6m
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1568176 mNorthing: 5204889 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP16
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
0.20
1.60
2.40
2.70
3.00
TOPSOIL Silty with some rootlets; Dark brown. Loose. Dry. Low plasticity.Friable.
SILT; Light grey with orange brown mottling. Stiff. Dry. Low plasticity. Friable.
PEAT with some silt and tree branches; Dark brown. Soft to firm. Saturated.Low plasticity. Fibrous.
Sandy GRAVEL; Light blue grey. Dense. Saturated. Gravel fine to coarsegrained and sub rounded. Sand coarse grained.
Sandy GRAVEL; Light yellow brown. Dense. Saturated. Gravel fine to coarsegrained and sub rounded. Sand coarse grained.
End of Test Pit at 3m (GW reached)
Last
Genera
ted:
8/1
2/2
011 3
:59:2
5 p
.m.
Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
Remarks:
Groundwater encountered @ 3.0m
Sa
mp
le
Wa
ter
Le
ve
l (m
)
Ele
va
tio
n (
m)
-1
-2
-3
-4
De
pth
(m
)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Gra
ph
ic L
og
Soil Description
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955 Sheet 1 of 1
Logged by: MHDInput by: MHDChecked by: JSMVerified by: JK
CO-ORDINATES NZTMEasting: 1568228 mNorthing: 5204806 mGround Level: 0 m
Data
base F
ile:
223094_T
ES
TP
IT_LO
GS
.GP
J,
Lib
rary
: C
OP
Y O
F C
HC
H L
IBR
AR
Y F
EB
2011.G
LB
, D
ata
tem
pla
te:
CH
CH
DA
TA
TE
MP
LA
TE
NO
V 2
010.G
DT
, Last
Genera
ted:
8/1
2/2
011.
Date Started: 30/09/2011Date Completed: 30/09/2011
Client: VB Properties 2008 LimitedProject Name: Northbrook Subdivision - RangioraLocation: See Location PlanProject Reference: 223094 - Northbrook Subdivision
TP17
TEST PIT INFORMATIONExcavator Type: 13 Tonne ExcavatorTest Pit Dimensions:Contractor: BG Contractors
Aurecon (New Zealand) Limited
Unit 1, 150 Cavendish Rd
PO BOX 1061
Christchurch 8140
New Zealand
www.aurecongroup.com
Email: christchurch@ap.aurecongroup.com
.
Shear
Vane T
ests
Penetr
om
ete
r T
ests
Geotechnical Assessment Report
Project 223094 | File 223094 Geotech Report Rev1 Second Issue.docx 20 December 2011 | Revision 1 Aurecon Page ii
Appendix D 2007 Test Pit Logs
Location
Logged By Weather Conditions
FI FineUndrained Shear Strength (kPa)
Measured Using a Hand Held Shear Vane1
25 50 75 100 125 150
Scala Penetrometer Test2
(Blows/ 50mm)
2 4 6 8 10 12
TOPSOIL, dark brown
Clayey SILT, ligth brown with orange mottling, stiff,
0.5 dry 3.5
Fine silty CLAY, light grey with orange mottling, firm
to stiff, dry
1 4
Fine silty CLAY, dark grey, firm to stiff, dry
1.5 4.5
PEAT with timber, black, soft, saturated
2 5
Clayey SILT with fine sand, grey, soft, moist
2.5 5.5
Fine to coarse SAND with rounded gravel, light
brown, loose, moist
END OF TEST PIT AT 2.8m
Water at the bottom of the test pit draining out of the
upper peat layer and the gravel at the bottom, rising
1 - Hand held shear vane test in accordance with BS1377:1990
2 - Scala Penetrometer Test in accordance with NZS4402:1986 for the first three meters
Test Descriptions:
High School Block, Rangiora P31346-002
Wat
er
Dep
th (
m)
Soi
l Sym
bol FACE 1
25/10/2007Project Job Number
Rangiora
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
Open Excavation LogTest Pit No.
Client Date
Wat
er
Dep
th (
m)
Soi
l Sym
bol FACE 1 Continued
Prenda Investments Ltd
aaaTP1
Connell Wagner Limited195 Hereford St. (PO Box 1061
Christchurch New Zealand
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Location
Logged By Weather Conditions
FI FineUndrained Shear Strength (kPa)
Measured Using a Hand Held Shear Vane1
25 50 75 100 125 150
Scala Penetrometer Test2
(Blows/ 50mm)
2 4 6 8 10 12
TOPSOIL, dark brown
Fine to coarse rounded GRAVEL with some sand,
light brown, dense, moist
Fine to coarse SILT with some clay, brown to grey, END OF TEST PIT AT 3.4m
0.5 firm, dry, Cu 130/20 kPa 3.5 Water at the bottom of the test pit draining out of the
upper peat layer and the gravel at the bottom, rising
1 4
Fine silty CLAY, light grey, stiff, moist
1.5 4.5
2 5
PEAT, black, soft to firm, wet to saturated
Fine silty CLAY with sand and some peat, grey
with orange mottling, soft to firm, moist,
Cu 62/10 kPa
PEAT, black, soft to firm, wet to saturated
Fine silty CLAY with sand and some peat, grey
2.5 with orange mottling, soft to firm, moist, 5.5
PEAT, black, soft to firm, wet to saturated
Fine silty CLAY with sand and some peat, grey
with orange mottling, soft to firm, moist,
PEAT, black, soft, wet
Fine to coarse sandy rounded GRAVEL, light grey
to blue, dense, moist
1 - Hand held shear vane test in accordance with BS1377:1990
2 - Scala Penetrometer Test in accordance with NZS4402:1986 for the first three meters
Open Excavation LogTest Pit No.
Client Date
Prenda Investments Ltd 25/10/2007Project Job Number
Rangiora
High School Block, Rangiora P31346-002
Wat
er
Dep
th (
m)
Soi
l Sym
bol FACE 1
Wat
er
Test Descriptions:
Dep
th (
m)
Soi
l Sym
bol FACE 1 Continued
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
aaaTP2
Connell Wagner Limited195 Hereford St. (PO Box 1061
Christchurch New Zealand
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Location
Logged By Weather Conditions
FI FineUndrained Shear Strength (kPa)
Measured Using a Hand Held Shear Vane1
25 50 75 100 125 150
Scala Penetrometer Test2
(Blows/ 50mm)
2 4 6 8 10 12
TOPSOIL, dark brown
Clayey fine to coarse SILT, brown to grey with Peat lense
orange mottling, firm to stiff, dry, Cu >140 kPa
Sandy fine to coarse rounded GRAVEL, light grey
0.5 3.5 to blue, loose
END OF TEST PIT AT 3.6m
Water at the bottom of the test pit draining out of the
upper peat layer and the gravel at the bottom, rising
CLAY with fine sand, brown, soft to firm, moist
1 4
1.5 4.5
PEAT with timber, black, soft, seepage
CLAY with fine to medium silt, organic material,
grey, soft, moist
PEAT layers mixed with clay material and silt
2 5
Peat lense
2.5 5.5
Peat lense
Peat lense
1 - Hand held shear vane test in accordance with BS1377:1990
2 - Scala Penetrometer Test in accordance with NZS4402:1986 for the first three meters
Test Descriptions:
High School Block, Rangiora P31346-002
Wat
er
Dep
th (
m)
Soi
l Sym
bol FACE 1
25/10/2007Project Job Number
Rangiora
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
Open Excavation LogTest Pit No.
Client Date
Wat
er
Dep
th (
m)
Soi
l Sym
bol FACE 1 Continued
Prenda Investments Ltd
aaaTP3
Connell Wagner Limited195 Hereford St. (PO Box 1061
Christchurch New Zealand
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Location
Logged By Weather Conditions
FI FineUndrained Shear Strength (kPa)
Measured Using a Hand Held Shear Vane1
25 50 75 100 125 150
Scala Penetrometer Test2
(Blows/ 50mm)
2 4 6 8 10 12
TOPSOIL, dark brown
Fine to coarse SILT, brown to grey with orange Peat lense
mottling, stiff, dry, Cu 115/25 kPa
0.5 3.5
SILT with some fine sand, brown to red, soft to firm, PEAT, black, soft, moist
moist
Fine to medium SILT with some clay, grey with
orange mottling, firm to stiff, moist
1 4
Fine to coarse rounded GRAVEL with some sand
END OF TEST PIT AT 4.3m
1.5 4.5
2 5
Silty CLAY, grey, soft, moist, Cu 24/5 kPa
Organic CLAY with timber, dark grey to black, soft,
becoming firm to depth, wet to saturated
2.5 5.5
Peat lense
Peat lense
1 - Hand held shear vane test in accordance with BS1377:1990
2 - Scala Penetrometer Test in accordance with NZS4402:1986 for the first three meters
Open Excavation LogTest Pit No.
Client Date
Prenda Investments Ltd 25/10/2007Project Job Number
Rangiora
High School Block, Rangiora P31346-002
Wat
er
Dep
th (
m)
Soi
l Sym
bol FACE 1
Wat
er
Test Descriptions:
Dep
th (
m)
Soi
l Sym
bol FACE 1 Continued
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
aaaTP4
Connell Wagner Limited195 Hereford St. (PO Box 1061
Christchurch New Zealand
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Location
Logged By Weather Conditions
FI FineUndrained Shear Strength (kPa)
Measured Using a Hand Held Shear Vane1
25 50 75 100 125 150
Scala Penetrometer Test2
(Blows/ 50mm)
2 4 6 8 10 12
TOPSOIL, dark brown
Peat lense
Fine to medium sandy SILT, grey to light brown
with orange mottling, firm to stiff, surface moist PEAT with organic material, black, stiff,
moist
0.5 3.5 Organic silty CLAY with peat and timber, grey to
black, soft, moist
Peat lense
SILT with some clay, light grey to blue, firm, moist
1 4
END OF TEST PIT 4.3m
Clayey fine SILT, light grey with orange mottling, Water rising rapidly
firm to stiff, moist
1.5 4.5
2 5
PEAT with timber, black, soft, wet to saturated
2.5 5.5
Organic silty-CLAY, with peat and timber, grey to
black, soft, moist
Peat lense
1 - Hand held shear vane test in accordance with BS1377:1990
2 - Scala Penetrometer Test in accordance with NZS4402:1986 for the first three meters
Test Descriptions:
High School Block, Rangiora P31346-002
Wat
er
Dep
th (
m)
Soi
l Sym
bol FACE 1
25/10/2007Project Job Number
Rangiora
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
Open Excavation LogTest Pit No.
Client Date
Wat
er
Dep
th (
m)
Soi
l Sym
bol FACE 1 Continued
Prenda Investments Ltd
aaaTP5
Connell Wagner Limited195 Hereford St. (PO Box 1061
Christchurch New Zealand
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Location
Logged By Weather Conditions
FI FineUndrained Shear Strength (kPa)
Measured Using a Hand Held Shear Vane1
25 50 75 100 125 150
Scala Penetrometer Test2
(Blows/ 50mm)
2 4 6 8 10 12
TOPSOIL, dark brown
Fine sandy SILT, light brown to light grey, stiff, dry
Fine SILT with some clay and some fine sand, light
0.5 brown with orange mottling, soft to firm, moist 3.5
1 4
1.5 4.5
2 5
Clayey SILT, light grey with orange mottling, soft PEAT, black, soft, moist
to firm, moist
END OF TEST PIT AT 5.3m
PEAT, dark brown, firm, moist to wet
2.5 5.5
Clayey SILT, grey, firm, moist, Cu 50/12 kPa
1 - Hand held shear vane test in accordance with BS1377:1990
2 - Scala Penetrometer Test in accordance with NZS4402:1986 for the first three meters
Open Excavation LogTest Pit No.
Client Date
Prenda Investments Ltd 25/10/2007Project Job Number
Rangiora
High School Block, Rangiora P31346-002
Wat
er
Dep
th (
m)
Soi
l Sym
bol FACE 1
Wat
er
Test Descriptions:
Dep
th (
m)
Soi
l Sym
bol FACE 1 Continued
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
aaaTP6
Connell Wagner Limited195 Hereford St. (PO Box 1061
Christchurch New Zealand
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Location
Logged By Weather Conditions
FI FineUndrained Shear Strength (kPa)
Measured Using a Hand Held Shear Vane1
25 50 75 100 125 150
Scala Penetrometer Test2
(Blows/ 50mm)
2 4 6 8 10 12
TOPSOIL, dark brown
Fine sandy SILT, brown with grey and orange
mottling, firm to stiff, dry, becoming moist with depth
0.5 3.5
Fine sandy SILT, grey, firm, moist
1 4
SILT with some sand and some clay, grey, soft to
1.5 4.5 firm, moist
END OF TEST PIT AT 4.9m
2 5
Fine to medium sandy SILT, grey, soft, moist
2.5 5.5
Fine to coarse SAND with some silt, grey, loose,
moist
1 - Hand held shear vane test in accordance with BS1377:1990
2 - Scala Penetrometer Test in accordance with NZS4402:1986 for the first three meters
Test Descriptions:
High School Block, Rangiora P31346-002
Wat
er
Dep
th (
m)
Soi
l Sym
bol FACE 1
25/10/2007Project Job Number
Rangiora
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
Open Excavation LogTest Pit No.
Client Date
Wat
er
Dep
th (
m)
Soi
l Sym
bol FACE 1 Continued
Prenda Investments Ltd
aaaTP7
Connell Wagner Limited195 Hereford St. (PO Box 1061
Christchurch New Zealand
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Location
Logged By Weather Conditions
FI FineUndrained Shear Strength (kPa)
Measured Using a Hand Held Shear Vane1
25 50 75 100 125 150
Scala Penetrometer Test2
(Blows/ 50mm)
2 4 6 8 10 12
TOPSOIL, dark brown Fine to medium SAND with some silt, light grey,
dense
Silty fine to medium SAND, light brown to grey with
orange mottling, loose
0.5 3.5
END OF TEST PIT AT 3.5m
1 4
1.5 4.5
Fine to medium SAND with silt, light brown with
grey mottling, soft, moist
2 5
2.5 5.5
Fine to medium sandy SILT, grey, soft, moist
1 - Hand held shear vane test in accordance with BS1377:1990
2 - Scala Penetrometer Test in accordance with NZS4402:1986 for the first three meters
Open Excavation LogTest Pit No.
Client Date
Prenda Investments Ltd 25/10/2007Project Job Number
Rangiora
High School Block, Rangiora P31346-002
Wat
er
Dep
th (
m)
Soi
l Sym
bol FACE 1
Wat
er
Test Descriptions:
Dep
th (
m)
Soi
l Sym
bol FACE 1 Continued
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
SOIL DESCRIPTION:
Colour, structure, weathering, subordinate/ main / minor
COMPONENTS.
aaaTP8
Connell Wagner Limited195 Hereford St. (PO Box 1061
Christchurch New Zealand
Telephone: +64 3 366 0821
Facsimile: +64 3 379 6955
Geotechnical Assessment Report
Project 223094 | File 223094 Geotech Report Rev1 Second Issue.docx 20 December 2011 | Revision 1 Aurecon Page iii
Appendix E ECan Borehole Logs
Geotechnical Assessment Report
Project 223094 | File 223094 Geotech Report Rev1 Second Issue.docx 20 December 2011 | Revision 1 Aurecon Page iv
Appendix F LiquefyPro Settlements
Job Northbrook Sub Division
Job No. 223094
Client VB Properties 2008 Limited
Date 21-Nov-11
LIQUEFACTION ASSESSMENT RESULTS
SLS 1170 EQ M = 7.5 PGA = 0.20g
ULS 1170 EQ M = 7.5 PGA = 0.34g
CALCULATED SETTLEMENT in mm (Tokimatsu and Seed)
1 0 0
2 0 0
3 0 0
4 0 0
5 0 0
6 0 0
7 0 5
8 0 0
9 0 10
10 0 0
11 0 0
12 0 5
13 0 0
14 0 0
15 0 0
16 0 15
Min 0 0
Ave 0 2
Max 0 15
Over 50mm Settlement
Over 40mm Settlement
Over 30mm Settlement
SLS 1170 EQ
Settlement (mm)
ULS 1170 EQ
Settlement (mm)Test / CPT
223094 Settlements Liquefy pro.xls
1 2.4 0.0 N
2 3.0 0.0 N
3 3.9 0.3 N
4 3.7 0.2 N
5 2.5 0.0 N
6 >5.5 0.0 N
7 4.4 0.2 N
8 >5 0.0 N
9 2.3 0.2 N
10 5.7 0.1 N
11 >6.5 0.0 N
12 3.7 0.1 N
13 >8 0.0 N
14 >5 0.0 N
15 >6.5 0.0 N
16 3.6 0.5 N
1 2.4 0.1 N
2 >3 0.0 N
3 3.9 0.3 N
4 3.7 0.2 N
5 >3.2 0.0 N
6 >5.5 0.0 N
7 4.3 0.2 N
8 >5 0.0 N
9 2.3 0.2 N
10 5.5 0.1 N
11 >6.5 0.0 N
12 3.7 0.9 N
13 4.1 0.1 N
14 >5 0.0 N
15 4.0 0.1 N
16 3.5 0.6 N
Damaging Surface
Expression
Thickness of Upper
Liquefiable Layer (m)
Crust Thickness
(m)
Damaging Surface
Expression
Crust Thickness
(m)
Thickness of Upper
Liquefiable Layer (m)Test / CPT
Test / CPT
SLS 1170 EQ
ULS 1170 EQ
223094 Settlements Liquefy pro.xls
1 N N
2 N N
3 N N
4 N N
5 N N
6 N N
7 N N
8 N N
9 N N
10 N N
11 N N
12 N N
13 N N
14 N N
15 N N
16 N N
Test / CPTSLS 1170 EQ Settlement (mm)ULS 1170 EQ Settlement (mm)
1 0 0
2 0 0
3 0 1
4 0 2
5 0 0
6 0 0
7 2 3
8 0 0
9 1 8
10 0 1
11 0 1
12 0 7
13 0 1
14 0 1
15 0 1
16 2 16
Min 0 0
Ave 0 3
Max 2 16
Damaging Surface Expression
ULS 1170 EQSLS 1170 EQTest / CPT
223094 Settlements Liquefy pro.xls
Geotechnical Assessment Report
Project 223094 | File 223094 Geotech Report Rev1 Second Issue.docx 20 December 2011 | Revision 1 Aurecon Page v
Appendix G LiquefyPro Results
Liq
uefy
Pro
C
ivilT
ech S
oft
ware
U
SA
ww
w.c
ivilt
ech.c
om
CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT1 Water Depth=2.3 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
Silty-CLAY
PEAT
Silty-CLAY
Silty-SAND
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.00 cm
0 (cm) 1
fs1=1.00
Liq
uefy
Pro
C
ivilT
ech S
oft
ware
U
SA
ww
w.c
ivilt
ech.c
om
CivilTech Corporation
LIQUEFACTION ANALYSISNorthbroook Sub-division
SLS Event Plate A-1
Hole No.=CPT2 Water Depth=3.5 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
Silty-CLAY
SANDSilty-CLAY
PEAT
Silty-CLAY
Silty-SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.00 cm
0 (cm) 1
fs1=1.00
Liq
uefy
Pro
C
ivilT
ech S
oft
ware
U
SA
ww
w.c
ivilt
ech.c
om
CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT3 Water Depth=3.8 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
PEAT
Silty-CLAY
PEAT
Silty-CLAY
Silty-SAND
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.00 cm
0 (cm) 1
fs1=1.00
Liq
uefy
Pro
C
ivilT
ech S
oft
ware
U
SA
ww
w.c
ivilt
ech.c
om
CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT4 Water Depth=3.6 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
Silty-CLAY
PEAT
Silty-CLAY
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.01 cm
0 (cm) 1
fs1=1.00
Liq
uefy
Pro
C
ivilT
ech S
oft
ware
U
SA
ww
w.c
ivilt
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT5 Water Depth=3.2 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
SILT
Silty-CLAY
PEAT
Silty-CLAY
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.01 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT6 Water Depth=3.5 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
6
7
8
9
10
SILT
Silty-CLAY
PEAT
Silty-CLAY
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.01 cm
0 (cm) 1
fs1=1.00
Liq
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT7 Water Depth=2.2 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
6
7
8
9
10
SILT
Silty-CLAY
PEAT
Silty-CLAY
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.15 cm
0 (cm) 1
fs1=1.00
Liq
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT8 Water Depth=4 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
PEATSilty-CLAY
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.00 cm
0 (cm) 1
fs1=1.00
Liq
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT9 Water Depth=2.3 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
PEATSILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.11 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT10 Water Depth=4 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
PEAT
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.01 cm
0 (cm) 1
fs1=1.00
Liq
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT11 Water Depth=5 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
Silty-SAND
Silty-CLAY
Silty-SAND
Silty-CLAY
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.04 cm
0 (cm) 1
fs1=1.00
Liq
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT12 Water Depth=3.5 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
6
7
8
9
10
SILT
PEATSILT
Silty-CLAY
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.04 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT13 Water Depth=3.5 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
6
7
8
9
10
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.02 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT14 Water Depth=5 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
6
7
8
9
10
SILT
Silty-SAND
Silty-CLAY
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.03 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT15 Water Depth=3.4 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
SILT
Silty-CLAY
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.03 cm
0 (cm) 1
fs1=1.00
Liq
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
SLS Event Plate A-1
Hole No.=CPT16 Water Depth=3.5 m Magnitude=7.5
Acceleration=0.2g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
Silty-SAND
Silty-CLAY
Silty-SAND
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.20 cm
0 (cm) 1
fs1=1.00
Liq
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT1 Water Depth=2.3 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
Silty-CLAY
PEAT
Silty-CLAY
Silty-SAND
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.03 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbroook Sub-division
ULS Event Plate A-1
Hole No.=CPT2 Water Depth=3.5 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
Silty-CLAY
SANDSilty-CLAY
PEAT
Silty-CLAY
Silty-SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.01 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT3 Water Depth=3.8 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
PEAT
Silty-CLAY
PEAT
Silty-CLAY
Silty-SAND
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.11 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT4 Water Depth=3.6 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
Silty-CLAY
PEAT
Silty-CLAY
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.20 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT5 Water Depth=3.2 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
SILT
Silty-CLAY
PEAT
Silty-CLAY
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.02 cm
0 (cm) 1
fs1=1.00
Liq
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT6 Water Depth=3.5 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
6
7
8
9
10
SILT
Silty-CLAY
PEAT
Silty-CLAY
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.01 cm
0 (cm) 1
fs1=1.00
Liq
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT7 Water Depth=2.2 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
6
7
8
9
10
SILT
Silty-CLAY
PEAT
Silty-CLAY
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.28 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT8 Water Depth=4 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
PEATSilty-CLAY
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.01 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT9 Water Depth=2.3 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
PEATSILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.76 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT10 Water Depth=4 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
PEAT
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.06 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT11 Water Depth=5 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
Silty-SAND
Silty-CLAY
Silty-SAND
Silty-CLAY
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.08 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT12 Water Depth=3.5 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
6
7
8
9
10
SILT
PEATSILT
Silty-CLAY
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.74 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT13 Water Depth=3.5 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
6
7
8
9
10
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.07 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT14 Water Depth=5 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
6
7
8
9
10
SILT
Silty-SAND
Silty-CLAY
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.06 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT15 Water Depth=3.4 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
SILT
Silty-CLAY
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 0.13 cm
0 (cm) 1
fs1=1.00
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CivilTech Corporation
LIQUEFACTION ANALYSISNorthbrook Sub-division
ULS Event Plate A-1
Hole No.=CPT16 Water Depth=3.5 m Magnitude=7.5
Acceleration=0.34g
(m)0
1
2
3
4
5
6
7
8
9
10
Silty-CLAY
Silty-SAND
Silty-CLAY
Silty-SAND
SILT
SAND
Shear Stress Ratio
CRR CSR fs1Shaded Zone has Liquefaction Potential
0 0.5Soil DescriptionFactor of Safety
0 51Settlement
SaturatedUnsaturat.
S = 1.62 cm
0 (cm) 10
fs1=1.00