CE 581 Final Report FINAL

CE 581 – Advanced geotechnical engineering

Geotechnical Engineering Report: Highland Drive Parking Garage and Site Improvements

Prepared for Dr. Gregg L. Fiegel and Mr. Nephi Derbidge

Juan Alvarez, Julio Amorim, Andy Flores, and Isabelle Rawlings

June 10, 2014

June 10, 2014

Gregg L. Fiegel, PhD, PE, GENephi DerbidgeDepartment of Civil and Environmental EngineeringCalifornia Polytechnic State UniversitySan Luis Obispo, CA 93407

Subject: Geotechnical Engineering ReportHighland Drive Parking Garage and Site Improvements Project

Dear Dr. Fiegel and Mr. Derbidge,

Transmitted herein per your request is our Geotechnical Engineering Report for the Highland Avenue Parking Garage and Site Improvements Project. The following report documents site and project description, local site conditions, geotechnical properties for design, and conclusions and recommendations.

The purpose of this document is to provide geotechnical recommendations for the Highland Drive Parking Garage and Visitor’s Center site. The report includes a summary and analysis of the geotechnical investigation for the project including laboratory and field investigations, and foundation recommendations for the proposed parking structure and Visitor’s Center. Construction concerns for the project are discussed and possible mitigation measures are provided for ease of constructability.

Please contact Mr. Juan Alvarez at [email protected] or Mr. Andrew Flores at [email protected] if you have any questions concerning this report. We look forward to working with you.

Sincerely,

Juan Alvarez Julio AmorimGeotechnical Specialist, EIT #150856 Geotechnical Specialist

Andrew Flores Isabelle RawlingsGeotechnical Specialist, EIT #149795 Geotechnical Specialist, EIT #149673

Table of Contents1. Introduction.................................................................................................................................................... 1

2. Site Description............................................................................................................................................... 1

3. Project Description.......................................................................................................................................... 1

4. Site Conditions................................................................................................................................................ 2

4.1 Work Performed................................................................................................................................................24.1.1 Site Reconnaissance and Field Exploration.................................................................................................24.1.2 Laboratory Tests.........................................................................................................................................2

4.1.2.1 Atterberg Limits...................................................................................................................................34.1.2.2 Hydrometer Method...........................................................................................................................34.1.2.3 Incremental Consolidation..................................................................................................................34.1.2.4 Moisture/Density Determination........................................................................................................34.1.2.5 Proctor Compaction............................................................................................................................34.1.2.6 Mechanical Sieve Analysis...................................................................................................................34.1.2.7 Swell and Expansion Index..................................................................................................................34.1.2.8 Unconsolidated Undrained Triaxial Test.............................................................................................44.1.2.9 Consolidated Undrained Triaxial Test..................................................................................................4

4.2 Soil Conditions...................................................................................................................................................44.2.1 Soil Encountered at Drill Hole 1..................................................................................................................44.2.2 Soil Encountered at Drill Hole 2..................................................................................................................4

4.3 Groundwater Conditions...................................................................................................................................45. Soil Property Evaluation.................................................................................................................................. 5

5.1 Generalized Soil Profile......................................................................................................................................5

5.2 Geotechnical Properties for Design...................................................................................................................75.2.1 Unit Weight, Moisture Content and Friction Angle....................................................................................75.2.2 Undrained Shear Strength..........................................................................................................................85.2.3 Consolidation and Stress History..............................................................................................................105.2.4 Shear Wave Velocity.................................................................................................................................125.2.5 Compaction Characteristics......................................................................................................................12

6. Conclusions and Recommendations............................................................................................................... 13

6.1 Summary of Findings.......................................................................................................................................13

6.2 Foundation Recommendations........................................................................................................................146.2.1 Visitor’s Center.........................................................................................................................................14

6.2.1.1 Settlement.........................................................................................................................................146.2.1.2 Swell/Expansion................................................................................................................................14

6.2.2 Parking Structure......................................................................................................................................146.2.2.1 Driven Piles.......................................................................................................................................146.2.2.2 Drilled Shafts.....................................................................................................................................15

6.3 Construction Considerations............................................................................................................................156.3.1 Use of Casing or Slurry..............................................................................................................................15

6.3.2 Concrete Placement.................................................................................................................................156.3.3 Non-Destructive Testing...........................................................................................................................156.3.4 Construction Sensitivity............................................................................................................................156.3.5 Existing Site Constraints...........................................................................................................................16

7. Closure...................................................................................................................................................................16

8. References.............................................................................................................................................................16

Appendix A – Site Plan and Subsurface Profile.........................................................................................................A-1

Appendix B – Field Exploration.................................................................................................................................B-1

Appendix C – Laboratory Testing..............................................................................................................................C-1

Appendix D – Calculations......................................................................................................................................D-41

List of TablesTABLE 1 - UNIT WEIGHT AND MOISTURE CONTENT.....................................................................................................7TABLE 2 - GENERALIZED UNDRAINED SHEAR STRENGTH...........................................................................................10TABLE 3 – OVERCONSOLIDATION RATIOS..................................................................................................................12TABLE 4 - SHEAR WAVE VELOCITY AND MODULUS....................................................................................................12TABLE 5 - COMPACTION CHARACTERISTICS OF SURFACE CLAY.................................................................................13TABLE 6 - GEOTECHNICAL PROPERTIES FOR DESIGN..................................................................................................13

List of FiguresFIGURE 1 - COMPARISON OF SOIL CLASSIFICATION (A) DH-1 (B) DH-2........................................................................6FIGURE 2 - DH-1 COMPARISON OF UNDRAINED SHEAR STRENGTH BY METHOD OBTAINED......................................9FIGURE 3 - DH-2 COMPARISON OF UNDRAINED SHEAR STRENGTH BY METHOD OBTAINED......................................9FIGURE 4 –DH-1 COMPARISON OF OCR BY METHOD OBTAINED...............................................................................11FIGURE 5 – DH-2 COMPARISON OF OCR BY METHOD OBTAINED..............................................................................11

Highland Drive Parking Structureand Site Improvements Project June 10, 2014

1. IntroductionThe purpose of this document is to provide geotechnical recommendations for the Highland Drive Parking Garage and Visitor’s Center site. The report includes a summary and analysis of the geotechnical investigation for the project including laboratory and field investigations, and foundation recommendations for the proposed parking structure and Visitor’s Center. Construction concerns for the project are discussed and possible mitigation measures are provided for ease of constructability.

For this Geotechnical Engineering Report for the Highland drive Parking Garage and Site Improvements Project, we will discuss the following: site and project description, site conditions, soil property evaluation, foundation recommendations, conclusions and recommendations.

2. Site DescriptionThe proposed Highland Drive Parking Garage and Site Improvements Project will be in northern San Luis Obispo, California on the California Polytechnic State University, San Luis Obispo campus, approximately ¼-mile east of California Highway 1. The site is bordered by Highland Avenue and the Crops Unit building to the northwest and citrus orchards to the northeast. The University campus is to the east and southeast of the site. Please refer to the Vicinity Map in Appendix A.

The proposed Visitor’s Center will be directly adjacent to Highland Drive; the proposed Parking Structure will be at the center of the site, approximately 300 feet southeast of Highland Drive. The general layout of the site relative to the subsurface explorations is shown on Building Layout in Appendix A.

The site is currently occupied by an unpaved perimeter road, small corn crops, and native plants and grasses. Overhead power lines run along the dirt perimeter road parallel to Highland Avenue. Seasonal streams run along the site at the west and southeast perimeter. The site is relatively flat, with gentle slopes to the south and west. Drainage follows the topography to the seasonal stream west adjacent of the site. Current site elevations range from approximately 290 to 295 feet above mean sea level.

3. Project DescriptionAs part of its 2020 Master Plan, California Polytechnic State University, San Luis Obispo intends to construct a 3-4 story reinforced concrete parking structure south of Highland Drive on the northwest vicinity of the campus. In addition to the parking structure, the University will construct a typical wood frame single story Visitor’s Center and associated temporary parking; this structure will be between the proposed parking structure and Highland Drive. Refer to Building Layout in Appendix A for more detail.

The parking structure will be similar to the existing structure on the south side of campus on 1 Grand Avenue. The parking structure will be supported by deep foundations; the Visitor’s Center will be supported by shallow foundations. Loads imparted by the structures are not expected to exceed approximately 1.5 kips per square foot (ksf) with wall loads of 1.5 kips per linear foot (klf), and 5 ksf with wall loads of 5 klf for the Visitor’s Center and the parking structure, respectively.

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The finish floor elevation at the ground floor of both structures will correspond approximately with the surface elevation of Highland Drive. Site grading will be minimal since the existing ground surface is relatively flat. Grading will be designed so surface water drains away from Highland Drive, towards the existing seasonal streams to the west and southeast.

As requested, a thorough geotechnical investigation was completed. We analyzed all field data and laboratory results on soil samples collected to make recommendations.

4. Site Conditions

4.1 Work PerformedWork performed for this Geotechnical Engineering Report included: site reconnaissance, subsurface field exploration including drilling of boreholes and Cone Penetrometer Testing (CPT), soil sampling, and laboratory testing. Data collected and analyzed was used to provide foundation recommendations.

4.1.1 Site Reconnaissance and Field ExplorationOur firm performed site reconnaissance before field exploration to gather site description information as well as construction constraints on April 15, 2014.

Earth Systems Pacific performed a subsurface investigation on the proposed project site during April 17 to April 24, 2014. Earth Systems utilized their truck-mounted Mobile B-53 drill rig to drill two 8-inch borings. Drill Hole 1 (DH-1) reached a depth of 41.5 feet below ground surface (bgs). Drill Hole 2 (DH-2) reached a depth of 45.5 feet bgs. The locations of the drill holes are shown on the attached CPT/Drill Hole Location Map in Appendix A. Logs recorded during drilling may be found in Boring Logs, in Appendix B.

Soil samples were collected and classified during drilling. Soil classification and descriptions were performed in accordance with the Unified Soil Classification System (ASTM D-2488). Earth Systems Pacific performed Standard Penetration Testing (SPT) at varying depths; both standard split spoon and modified California split spoon samplers were used. Thin-walled Shelby tubes were used to obtain relatively undisturbed soil samples. Additionally, bulk bag samples were collected from soil cuttings within the first 10.0 feet in both drill holes.

Gregg Drilling performed two CPT’s in the proximity of each drill hole on May 19, 2014. Continuous data was collected during exploration. In addition to regular CPT operations, Gregg Drilling performed 3 dissipation tests to estimate the location of the groundwater table (1 in CPT-1 and 2 in CPT-2), and 1 Shear Wave Velocity test in CPT-1 to obtain Shear Wave Velocities of subsurface soil layers. Detailed CPT data may be found in CPT Report in Appendix B. Locations of the CPT’s may be found on CPT/Drill Hole Location Map in Appendix A.

4.1.2 Laboratory TestsOur firm performed tests on the soil samples provided by Earth Systems Pacific. The tests included: Atterberg Limits, Hydrometer Tests, Incremental Consolidation Tests, Moisture/Density Tests, Proctor

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Compaction Testing, Mechanical Sieve Analysis, Swell and Expansion Index Testing, and both Unconsolidated Undrained (UU) and Consolidated Undrained (CU) Triaxial Testing. Refer to Appendix C for laboratory test results.

4.1.2.1 Atterberg Limits Atterberg Limits Measurements (ASTM D4318) evaluated liquid limit, plastic limit and plastic index of fine grained soil samples. Liquid limit was estimated as the water content corresponding to 25 blows on a Casagrande Cup. Plastic Limit was estimated as the water content corresponding to soil crumbling during rolling of a 1/8-inch thread. Casagrande’s Plasticity Chart uses Plastic Index and Liquid Limit to classify fine soils.

4.1.2.2 Hydrometer MethodThe Hydrometer Method (ASTM D422) evaluated grain size distributions of fine soil material (passing the number 10, 2.0-mm, sieve). Temperature and Hydrometer recorded specific gravity of fluid-soil mixtures at decreasing time intervals. Utilizing Stoke’s Law, the specific gravity readings estimate percent clay and silt. The Hydrometer Method classifies fine soils.

4.1.2.3 Incremental Consolidation Incremental Consolidation Testing (ASTM D2435) evaluated the relationship between axial stress and void ratio or strain of soil specimens subject to settlement beneath loading. Soil specimens were axially loaded with stress increments; increments are varied until the specimen reaches approximately 90 percent consolidation. A strain gage measured axial strain.

4.1.2.4 Moisture/Density Determination Standard methods evaluated water content (ASTM D2216) and the Drive Cylinder Method evaluated in-place density/unit weight (ASTM D2937). Weighting samples before and after oven-drying allows determination of water content and dry density. Phase relations were used to estimate total in-place density/unit weight.

4.1.2.5 Proctor CompactionProctor Compaction Testing (ASTM D698/D1557) evaluated optimum water content and max dry density of shallow soil samples. Soils of ranging water contents were placed in a mold and compacted, estimating a relationship between dry density and water content.

4.1.2.6 Mechanical Sieve AnalysisA Mechanical Sieve Analysis (ASTMD6913) estimated grain size distribution of soil material greater than 0.075-mm. The grain size distribution classifies coarse-grained soil.

4.1.2.7 Swell and Expansion IndexSwell testing (ASTM D2435) and Expansion Index (EI) of Soils (ASTM D4829) evaluated the potential for heave or swell of soil samples. Swell testing evaluates the swell pressure (the pressure at which no axial strain occurs), and EI is a unit less index to estimate expansion potential.

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4.1.2.8 Unconsolidated Undrained Triaxial TestUU Triaxial Tests (ASTM D2850) evaluated shear characteristics of cohesive soil samples. In two stages, the specimen was not allowed to consolidate while applying a confining pressure, and then the specimen was not allowed to drain while applying an axial load until failure.

4.1.2.9 Consolidated Undrained Triaxial TestCU Triaxial Tests (ASTM D4767) evaluated shear characteristics of cohesive soil samples. In two stages, the specimen was allowed to consolidate while applying a confining pressure, and then the specimen was not allowed to drain while applying an axial load until failure.

4.2 Soil ConditionsWe developed a cross-section between the two drill holes by careful observation, estimation and simplification of the soil strata in the subsurface of the site using boring logs, lab data and CPT interpretation. According to the Geologic Map of The San Luis Obispo Quadrangle (Wiegers, 2010), the subsurface consists of Alluvial deposited soils (Qal) above Franciscan Mélange (KJfm) sandstone and shale bedrock. Bedrock sloped downward to the west and south. Soil strata and layers also follow this slope. The attached Subsurface Profile in Appendix A illustrates an estimation of the subsurface in the vicinity of the Highland Avenue Parking Garage and Site Improvements Project Site.

4.2.1 Soil Encountered at Drill Hole 1Soils encountered at Drill Hole 1 of the site consisted of Fat Clay (CH), Sandy Lean Clay (sCL), Lean Clay (CL), and Clayey Sand (SC) above Sandstone and Shale. The fat clay layer is approximately 15 feet thick and is stiff to very stiff with depth. The sandy lean clay layer is approximately 20 feet thick, reaching a depth of 35 feet bgs, and its consistency was soft. Below the sandy lean clay is a lean clay layer approximately 7 feet thick, reaching a depth of 41 feet and its consistency was stiff. A seam of dense clayey sand was beneath the lean clay, until bedrock, encountered at a depth of 47 feet. Further discussion of soil properties is in Chapter 5.

4.2.2 Soil Encountered at Drill Hole 2Soils encountered at Drill Hole 2 of the site consisted of Fat Clay (CH), Sandy Lean Clay (sCL), and Clayey Sand (SC) above Sandstone and Shale. The fat clay layer is approximately 25 feet thick and is stiff to medium stiff with depth. The sandy lean clay layer is approximately 20 feet thick, reaching a depth of 45 feet bgs, and its consistency ranged from very soft to medium stiff with depth. The medium stiff clayey sand layer is approximately 30 feet thick, until bedrock, encountered at a depth of 75 feet. Further discussion of soil properties is in Chapter 5.

4.3 Groundwater ConditionsWe evaluated groundwater conditions at the site based on observations during drilling on April 17-24, 2014, and CPT dissipation tests performed on May 19, 2014.

DH-1 showed free water at an approximate depth of 16 feet bgs. A dissipation test performed during CPT-1 was ignored because the test was not performed properly within sandy material. DH-2 showed free water at an approximate depth of 23.5 feet bgs. A dissipation test performed during CPT-2 at a depth of 54.3 feet recorded pore water pressure of approximately 13.7 pounds per square inch (psi).

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Back-calculation of the hydrostatic head confirms the location of the groundwater table to be at a depth of 23 feet. It should be assumed that the groundwater table slopes down to the west and the south, following the slopes of the soil layers and bedrock. Groundwater was estimated to be approximately 16 to 23 feet bgs, although it should be noted that slight fluctuation of the groundwater table is expected to occur seasonally.

5. Soil Property Evaluation

5.1 Generalized Soil Profile The general profile consisted of Alluvial Deposits (Qal) on top of Franciscan Mélange Sandstone and Shale. The soil profile was estimated by inspection of Visual/Manuel classification during drilling, computerized soil classification during CPT operations, and soil classification during laboratory testing. Our firm examined all information to generate a simplified profile. Errors or mistakes may arise during Visual/Manuel classification which varies from CPT and laboratory data. Thus it is important to use all three sources to generate a soil profile. Figure 1 displays a comparison of the three classification systems with depth. The final simplified Subsurface Profile used a combination of the three and is in Appendix A.

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Figure 1 - Comparison of Soil Classification (A) DH-1 (B) DH-2

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24681012141618202224262830323436384042444648

DEPTH V/ M CPT LAB

SILTY SAND (SM)

CLAYEY SAND (SC)

GRAVEL AND SAND

SILT MIXTURES

CLAY

FAT CLAY (CH)

CLAYEY SAND (SC)

FAT CLAY (CH)

LEAN CLAY (CH)

2468

10121416182022242628303234363840424446485052545658606264666870727476

CLAY

SAND MIXTURES

FAT CLAY

LEAN CLAY

DEPTH V/ M CPT LAB

LEAN CLAY (CL)

SILTY SAND (SM)

SANDY LEAN CLAY (sCL)

SANDY LEAN CLAY (sCL)

WELL GRADED GRAVEL (GW)

FAT CLAY (CH)

GRAVEL AND SAND

SAND MIXTURES

(A)

(B)


The simplified soil profile consists of 15 to 25 feet of expansive Fat Clay (CH) that ranged from medium-stiff to stiff with depth. The fat clay has unit weights ranging from 121 to 127 pcf between the two drill-hole locations, and estimated undrained shear strength of 1.6 kips per square foot (ksf). The fat clay was found to be overconsolidated. Beneath the fat clay, 20 feet of Sandy Lean Clay (sCL) was encountered to depths of 35 to 45 feet that ranged from soft to medium stiff. The sandy lean clay has a unit weight of 121 to 127 pcf between the two drill hole locations, and estimated undrained shear strength of 0.8 ksf. A small layer of Lean Clay (CL) was encountered beneath the sandy lean clay in drill hole 1. This layer was approximately 6 feet thick, to a depth of 41 feet in drill hole 1. The lean clay has an estimated unit weight of 125 pcf, and an undrained shear strength of 1.2 ksf. The deepest soil layer, above the Franciscan bedrock was Clayey Sand (SC), ranging from 6 to 30 feet thick; this layer has an estimated unit weight of 130 pcf. Franciscan Mélange (KJfm) bedrock was encountered at 47 feet in drill hole 1 and 75 feet in drill hole 2. The soil layers and bedrock slope downward to the south and west.

Groundwater was located at 16 feet in drill hole 1, and at 23 feet in drill hole 2, approximately. Table 5 in Chapter 6 summarizes important geotechnical engineering properties of soil layers.

5.2 Geotechnical Properties for DesignOur firm evaluated geotechnical engineering properties of soil samples critical for foundation recommendations and engineering design. Properties were compared between laboratory data, boring logs, and CPT operations. For this section we will discuss our analysis including methodology, comparisons/discrepancies, generalization and property selection.

5.2.1 Unit Weight, Moisture Content and Friction AngleOur firm evaluated unit weights and moisture contents of in-situ soils determined through laboratory tests. We assumed unit weight and moisture content based on typical values for soil layers missing lab tests (Holtz et al 2011). Unit weight varied in each layer between drill hole locations. Our analysis averaged unit weights and moisture contents between locations. Unit weights and moisture contents are presented below in Table 1.

Table 1 - Unit Weight and Moisture Content

Soil LayerFat Clay (CH)

(Above GWT)

Fat Clay (CH) (Below

GWT)

Sandy Lean Clay (sCL)

Clayey Sand (SC)

Lean Clay (CL)

Unit Weight (pcf) 124 127 124 130 125

Moisture Content (%) 23 33 25 22 28

We estimated the sandy lean clay layer to be saturated year round; the water table was encountered near the soil boundary of the fat clay and the sandy lean clay. Additionally, capillary action of clay maintains a saturated state even as the water table fluctuates.

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We corrected SPT blow count recorded during drilling to obtain the friction angle of soil at varying depths. However, friction angle is not an appropriate strength property for the site because the subsurface consists primarily of clay. Undrained shear strength is used for the analysis of cohesive soils while friction angle is used for the analysis of coarse-grained soils. One SPT was performed in drill hole 1 in the clayey sand layer. Analysis and correlation estimated the friction angle of this layer to be approximately 40 degrees.

CPT correlations may be used to estimate relative density of coarse-grained soils. Relative density of the Clayey sand layer was estimated to be approximately 55 percent. Relative density does not apply to cohesive soils. Friction angle and relative density is not presented for remaining soil layers.

5.2.2 Undrained Shear Strength Shear strength is an important soil characteristic which depends on the stresses applied, time of consolidation, strain rate, and the stress history experienced by the soil. Cohesive soils utilize undrained shear strength because water does not flow out of the soil immediately after loading. Undrained shear strength is used in bearing capacity analysis of cohesive soils. In a purely cohesive soil, undrained shear strength is equal to cohesion, c’.

Shear strength values were estimated from: Unconsolidated Undrained triaxial tests in the laboratory, during CPT operations through known correlations to soil behavior, and hand tools including pocket penetrometer and hand torvane devices during drill operations. Figure 2 and 3 displays variation in undrained shear strength in the soil profile between methods.

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Figure 2 - DH-1 Comparison of Undrained Shear Strength by Method Obtained

Figure 3 - DH-2 Comparison of Undrained Shear Strength by Method Obtained

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As indicated above, variation in shear strength occurs between methodologies. UU Tests indicated in red were performed on Modified California samples and thin-walled Shelby tube samples. The UU results are less reliable for samples collected using the Modified California samplers due to higher disturbance caused by hammer impact. It may explain the low shear strength values recorded between depths of 20 and 35 feet in drill hole 1 shown on Figure 2. Furthermore, in examination of the UU results, the three samples between these depths did not achieve full shear failure even though they reached 15% strain. Aside from these few uncertainties, the lab tests agree with and follow the general trend of the CPT results. The field tests are a rough estimate of shear strength rather than one to be used in analysis.

After careful inspection, we selected the following shear strength values representing each soil layer encompassing the entire site in Table 2.

Table 2 - Generalized Undrained Shear Strength

Soil Layer Fat Clay (CH) Sandy Lean Clay (sCL) Clayey Sand (SC) Lean Clay (CL)

Undrained Shear Strength (ksf) 1.6 0.8 0.8 1.2

5.2.3 Consolidation and Stress HistoryOur firm evaluated stress history of cohesive soil samples at varying depths. Stress history can be used to estimate degree and rate of consolidation under loading conditions. Soils can be classified as either normally consolidated or overconsolidated. Normally consolidated soils typically have lower shear strength values and consolidate more; overconsolidated soils typically have higher shear strength values and consolidate less.

Soils encountered on site were overconsolidated near the surface and becoming normally consolidated with depth. Overconsolidation ratio (OCR) is the ratio of maximum past pressure felt by the soil to the existing; normally consolidated soils have an OCR of 1 while overconsolidated soils have an OCR greater than 1. Soils at deeper depths are affected by higher pressures similar to the maximum past pressure resulting in an OCR of approximately 1, or normally consolidated. Soils at shallower depths experience less pressure than the maximum past pressure resulting in an OCR greater than 1, or overconsolidated.

Figures 4 and 5 present the measured overconsolidation ratio during CPT operations and the evaluated overconsolidation ratio during laboratory testing with depth. As expected, OCR decreases with depth in both drill holes. The discrepancy between lab and CPT estimations may be explained by the correlation utilized during CPT operations. CPT operations estimated OCR from measured shear strength; shear strength is based on cone resistance, overburden stress and a dimensionless parameter, Nkt. Our analysis assumed an Nkt value of 14 although it can be varied to fit the soil type.

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Figure 4 –DH-1 Comparison of OCR by Method Obtained

Figure 5 – DH-2 Comparison of OCR by Method Obtained

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After careful inspection, we selected the following overconsolidation ratios representing each soil layer encompassing the entire site in Table 3.

Table 3 – Overconsolidation Ratios


OCR 5 2 - 1

Fat clay material encountered near the surface was estimated to have an OCR of 5. This is typical of heavily overconsolidated clays, as expected of surface materials. The soil is heavily overconsolidated because with the addition of the 5 ksf load expected from the parking structure, the maximum past pressure is still greater than the expected pressures post-construction. The sandy lean clay is overconsolidated and the lean clay is normally consolidated. The clayey sand was not assigned a value because OCR is not applicable to coarse-grained soils.

Settlement will not be a concern for deep foundations of the parking structure but will be for shallow foundations of the Visitor’s Center. Settlement analysis evaluated the settlement of fat clay material under expected loading of the Visitor’s Center. The surface fat clay layer will be most influenced by induced load and susceptible to settlement. The expected settlement was approximately greater than 8 inches in this clay layer. Refer to Chapter 6 for further information.

5.2.4 Shear Wave Velocity CPT-1 operation recorded shear wave velocity measurements with respect to depth. Shear wave velocity is an indicator of consistency and can be correlated to Young’s modulus of the soil. It can also be used to estimate liquefaction potential in saturated sandy soils; the site contains clay soils or sands with high clay content resulting in a low liquefaction potential. Table 4 presents shear wave velocities and Young’s modulus for each layer.

Table 4 - Shear Wave Velocity and Modulus


Shear Wave Velocity (ft/s) 200 725 1000 1050

Young’s Modulus (tsf) 75 1000 1850 2050

5.2.5 Compaction CharacteristicsWe performed modified proctor tests on soils found within 10 feet of the surface to estimate maximum dry unit weight and optimum moisture content. We recommend compaction of surface soils to at least 90% of the maximum dry unit weight during ground improvement of the Visitors’ Center building pad. Maximum dry unit weight and optimum moisture content are presented in Table 5.

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Table 5 - Compaction Characteristics of Surface Clay

Soil Layer Fat Clay (CH)Maximum Dry Unit Weight (pcf) 110Optimum Moisture Content (%) 19

6. Conclusions and Recommendations

6.1 Summary of Findings The site contains fat clay at the surface to depths of approximately 15 to 18 feet bgs. A layer of

sandy lean clay was found below and extends to approximately 25 to 45 feet bgs. A layer of lean clay was encountered on the eastern side of the site extending to approximately 41 feet bgs. A layer of clayey sand was encountered below the sandy lean clay/lean clay extending approximately 6 to 30 feet bgs. A competent Franciscan Formation underlies the site at depths varying from approximately 47 to 75 feet bgs.

Soil layers and bedrock slope downward to the west and south. Groundwater was encountered at 16 and 23 feet bgs, sloping to the west and south Table 6 displays soil properties for design that were evaluated using field and laboratory data:

Table 6 - Geotechnical Properties for Design

Soil Layer USCS Classification

Unit Weight

(pcf)

Moisture Content

(%)

Undrained Shear

Strength (ksf)

OCR

Shear Wave

Velocity (ft/s)

Young’s Modulus

(tsf)

Max Dry Unit

Weight (pcf)

Optimum Water

Content (%)

Fat Clay (Above GWT)

CH 124 23 1.6 5 200 75 110 19

Fat Clay (Below GWT)

CH 127 33 1.6 5 200 75 110 19

Sandy Lean Clay sCL 124 25 0.8 2 725 1000 - -

Lean Clay CL 125 22 1.2 1 1000 - 1850 -Clayey Sand SC 130 28 0.8 - 1050 - 2050 -

It is recommended that drilled shaft foundations be used for the parking structure to the depth of the Franciscan Formation.

It is recommended that shallow mat foundations be used for the Visitor’s Center.

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6.2 Foundation Recommendations

6.2.1 Visitor’s Center We recommend use of shallow mat foundations for the Visitor’s Center structure. The structure will be constructed of light wood framing. Dead plus live loads are not expected to exceed 2.0 ksf. Shallow foundations will be placed on the fat clay layer; this material was evaluated to have an undrained shear strength of 1.6 ksf. Shallow foundations on the fat clay will be suitable to support these relatively low loads. Settlement of the shallow foundations is expected to be significant. Mat foundations are recommended due to the settlement and swell/expansion potential of the fat clay material.

6.2.1.1 SettlementThe fat clay material is expected to settle significantly beneath the load imparted by the Visitor’s Center. Analysis estimated settlement to be greater than 8 inches. Fat Clay encountered near the surface was estimated to be heavily overconsolidated. Settlement of clay materials occurs over extensive periods of time, such as months or years. However, during field exploration small sand seams were encountered intermittently in clay layers. While these seams were ignored in the general analysis and profile, they may increase the rate of settlement in the clay due to faster drainage rates in sand then clay. Mat foundations are effective at limiting differential settlement.

6.2.1.2 Swell/ExpansionThe fat clay material was evaluated to be expansive. The expansion index (EI) was evaluated to be approximately 100 during laboratory testing. Generally, expansion becomes a concern for design when the EI approaches 100. Expansive or swelling soils are particularly problematic in areas of groundwater fluctuation, called the active zone. The fat clay material ranges from 15 to 25 feet bgs; because the groundwater table was encountered between 16 and 23 feet bgs, the fat clay material is expected to be susceptible to groundwater fluctuation. Shallow mat foundations are recommended to combat soil expansion. Other methods to combat expansive soils include: use of pre- or post-tension dowels, increasing the thickness of the slab and footings, increasing reinforcement area in slab and footings, moisture conditioning clay material to discourage water content fluctuation.

6.2.2 Parking Structure

6.2.2.1 Driven PilesWe do not recommend use of driven piles for the Highland Avenue parking structure. Pile driving operations produce excessive noise and vibration. The project site is on The Cal Poly University Campus and the Crops Unit building is only several hundred feet to the northeast. Noise and vibration will be a disturbance to sensitive Cal Poly residents, students and staff.

In addition the site conditions and soils present are primarily clay; clay materials typically do not provide large side resistances on piles. It is possible that deep foundation design will rely on end bearing resistance on bedrock material. End area of driven piles is relatively small so rendering proper end bearing values difficult.

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6.2.2.2 Drilled ShaftsWe recommend the use of drilled shaft foundations for the Highland Avenue parking structure. Large diameter drilled shafts will be suitable to support the expected loads imparted by the parking structure of approximately 5.0 ksf. Clay material provides less side axial resistance than sands. Additionally, the potential for settlement in the clay layers creates ‘downdrag’, effectively reducing side resistance and additional axial demand. Deep foundations implemented will reply on end bearing for axial resistance. End bearing can be achieved by using large diameter drilled shafts to the bedrock material. Drilled shafts are preferable for the subsurface at this site due to the varying elevations of the Franciscan Formation; drilled shafts have the benefit of having flexible lengths and can accommodate for fluctuations in depth to competent material.

Additionally, drilled shaft construction reduces noise pollution and maintains a quiet environment for the university.

6.3 Construction Considerations

6.3.1 Use of Casing or SlurryWe recommend that drilled shafts are constructed under wet conditions using slurry due to the presence of groundwater. Clay material on site range from soft to stiff. Soft clays have a tendency to ‘neck’ during drilled shaft construction, where the hollow shaft can collapse inward. Slurry maintains a net positive pore water pressure against the walls of the excavation and helps stabilize walls. Three types of slurry can be used: mineral, synthetic or natural. Use of slurry also encourages the full concrete-soil bond develops as concrete sets. Side resistance developed is dependent this bond. Using slurry will encourage the maximum axial resistances of the foundation.

Casing also stabilizes walls and allows groundwater to be pumped out. Casing allows construction personnel to properly clean out the bottom of the hole. With the same concrete-soil bond discussed above, cleaning out the base of the excavation encourages full base resistance mobilization.

6.3.2 Concrete PlacementThe concrete used for a drilled shaft will be placed by tremie pipe to the bottom of the excavation. The concrete should have a relatively high slump to pour evenly and discourage formation of voids. The tremie tip elevation should be kept 5.0 to 10.0 feet below the surface of rising concrete to maintain proper head and so concrete does not mix with slurry.

6.3.3 Non-Destructive Testing We recommend conducting non-destructive testing during shaft construction. Detection and remediation of concrete anomalies in proximity to the depth of maximum shaft bending moment is important for structural integrity.

6.3.4 Construction Sensitivity Because the depth to bedrock is approximate and varies, reliance on driller expertise will be critical in determining whether required soil layer has been reached. We recommend that a geotechnical engineering is onsite during construction to confirm the shaft is built to specifications.

15


Quality of drilled shaft foundations is highly sensitive to the construction process and quality. Construction personnel should clearly understand the drilled shaft method and proper implementation on the project. It proposed shaft installation methods or results differ from plans or specifications, the design engineer should be notified to minimize the list of improper installation.

6.3.5 Existing Site Constraints Blackhammer Engineering performed site reconnaissance on April 15, 2014 where sensitive site constrains were identified. Overhead power lines span along the north perimeter of the site and irrigation pipes span the west and east perimeter of the site. Careful practices should be taken to avoid damaging the power lines or irrigation pipes.

7. Closure

This report is intended for the exclusive use of Dr. Fiegel and Mr. Derbidge at California Polytechnic State University, San Luis Obispo for the Highland Avenue Parking Garage and Site Improvements Project. Blackhammer Engineering does not accept any liability for third party interpretation of this report. The necessity of further interpretation or modification of this report should be reported to Blackhammer Engineering. Additional projects outside of the Highland Avenue Parking Garage and Site Improvements Project should not rely on this report for the interpretation of the subsurface profile or site conditions and should instead rely on an independent, project specific field investigation.

This report is to be used in its entirety without the independent use of certain sections or the specific design recommendations. Use of any information from this report outside explicit recommendations by Blackhammer Engineering will terminate any and all liability held by Blackhammer Engineering.

All data, design recommendations, and interpretations contained in this report are the property of Blackhammer Engineering.

8. ReferencesASTM International, (2007). “Particle-Size Analysis of Soils,” ASTM D422.

ASTM International, (2007). “Unconsolidated-Undrained Triaxial Compression Test on Cohesive Soils,” ASTM D2850.

ASTM International, (2008). “One-Dimensional Swell or Collapse of Cohesive Soils,” ASTM D4546.

ASTM International, (2009). “Description and Identification of Soils (Visual-Manual Procedure),” ASTM D2488.

ASTM International, (2009). “Particle-Size Distribution (Gradation) of Soils Using Sieve Analysis,” ASTM D6913.

16


ASTM International, (2010). “Laboratory Determination of Water (Moisture) Content of Soil and Rock by Mass,” ASTM D2435/D2435M.

ASTM International, (2010). “Density of Soil in Place by the Drive-Cylinder Method,” ASTM D2937.

ASTM International, (2010). “Liquid Limit, Plastic Limit and Plasticity Index of Soils,” ASTM D4318.

ASTM International, (2011). “Expansion Index of Soils,” ASTM D4829.

ASTM International, (2011). “One-Dimensional Consolidation Properties of Soils Using Incremental Loading,” ASTM D2216.

ASTM International, (2012). “Field Logging of Subsurface Explorations of Soil and Rock,” ASTM D5434.

ASTM International, (2012). “Laboratory Compaction Characteristics of Soil Using Standard Effort,” ASTM D698.

ASTM International, (2012). “Laboratory Compaction Characteristics of Soil Using Modified Effort,” ASTM D1557.

Brown, D.A., J.P. Turner, and R.J. Castelli (2010). “Drilled Shafts: Construction Procedures and LRFD Design Methods,” FHWA NHI-10-016, Federal Highway Administration, Washington D.C.

Coduto, D. P., M. R. Yeung, and W. A. Kitch, Geotechnical Engineering: Principles and Practices. Upper Saddle River, Pearson Education, 2011.

Holtz, R. and W. Kovacs, An Introduction to Geotechnical Engineering. Pearson Education, 2011. Print

Salgado, R., The Engineering of Foundations. Boston: McGraw Hill, 2008. Print.

Wiegers, Mark (2010). “ Geologic Map of The San Luis Obispo Quadrangle,” California Department of Conservation, California Geological Survey.

17


Appendix A – Site Plan and Subsurface Profile

Appendix A includes the following:

Figure A-1: Vicinity Map of Highland Avenue Project

Figure A-2: Building Layout and CPT/Drill Hole Locations

Figure A-3: Generalized Profile Cross-Section A-A’

Figure A-4: Subsurface Profile Cross-Section A-A’

18

1

Figure A-1: Vicinity Map of Highland Avenue Project

2

Figure A-2: Building Layout and CPT/Drill Hole Locations

3

Appendix B – Field Exploration

Appendix B includes the following:

B-2: Boring Logs

B-6: Gregg Drilling CPT Report

1

LOCATION: Cal Poly crop field, 700 feet south of

Highland Drive, east road, 5 feet east of path

SURFACE EL: 290 +/- (rel. MSL datum)

ALLUVIUM (Qal)

290 2 FAT CLAY (CH): stiff, dark brown, moist

1 (15) 87 26 68 45

288 4 1A 70 52

286 6 2 9 - sand present PP 2.25

284 8 3 (30) - very stiff, brown, moist, pinhole voids present 127 104 22 58 39

1B iron oxide staining 282 10

4 14 PP 3.0

280 12

278 14

276 16 5 (13) - seam of sand 127 104 23 32 21

- groundwater encounted at 16.0 feet274 18 CLAYEY SAND (SC): soft, olive brown, wet 35 21

6272 20

7 (7) - loose, contains gravel at bottom of sampler 115 16 34 26 9

270 22

268 24

266 26 8 (3) - very loose, trace gravel 97 27

264 28

SILTY SAND (SM): very loose, olive brown, wet262 30

9 103 23

260 32 - clayey

258 34

256 36 10 (21) LEAN CLAY (CL): stiff, olive brown, wet, mottled with 92 31

iron oxide

COMPLETTION DEPTH: 41.5 feet DRILLING METHOD: 8-inch dia. HSADEPTH TO WATER: 16.0 feet HAMMER TYPE: Automatic TripBACKFILLED WITH: Cutti ngs, cold patch DRILLED BY: Earth Systems Pacific, INC. DRILLING DATE: April 17, 2014 LOGGED BY: Group 4

SAM

PLER

S

ELEV

ATIO

N (F

T)

DEPT

H (F

T)

MAT

ERIA

LSY

MBO

L

SAM

PLE

NO.

PLAS

TICI

TY IN

DEX,

PI

UNDR

AINE

D SH

EAR

STRE

NGTH

(ksf)

MATERIAL DESCRIPTION

LOG OF DRILL HOLE NO. DH-1

SAM

PLER

BLO

WCO

UNT

TOTA

L UN

IT W

T (p

cf)

DRY

UNIT

WT

(pcf

)

WAT

ER C

ONTE

NT (%

)

%PA

SSIN

G #2

00

LIQU

ID L

IMIT

, LL

2

LOCATION: South abutment, 30’ south of abutment

wall (proposed)


254 38 11 114 16

- sandy, yellow-brown252 40

12 29 CLAYEY SAND (SC): medium dense, brown, wet 33 17 PP 1.75

250 42 - weathered sandstone, Franciscan Formation

BORING TERMINATED AT 41.5 FEET248 44

246 46

244 48

242 50

240 52

238 54

236 56

234 58

232 60

230 62

228 64

226 66

224 68

222 70

220 72



WAT

ER C

ONTE

NT (%

)

%PA

SSIN

G #2

00

LIQU

ID L

IMIT

, LL

PLAS

TICI

TY IN

DEX,

PI

UNDR

AINE

D SH

EAR

STRE

NGTH

(ksf)

ELEV

ATIO

N (F

T)


TOTA

L UN

IT W

T (p

cf)

DRY

UNIT

WT

(pcf

)

SAM

PLER

BLO

WCO

UNT

SAM

PLER

S

SAM

PLE

NO.

MAT

ERIA

LSY

MBO

L

DEPT

H (F

T)

3


Highland Drive, west road, 5 feet east of path


ALLUVIUM (Qal)

288 2 WELL GRADED GRAVEL WITH SAND (GW): medium

1 (18) dense, gray, dry 3.6

286 4

FAT CLAY (CH): medium stiff, dark brown, moist284 6 2 9 27 66 46 PP 4.3

282 8 1A 24 52 30

3 (22) 121 99 23 PP 3.6

280 10

4 - with sand 55 33

278 12

1B276 14

LEAN CLAY (CL): soft to medium stiff, red-gray, moist274 16 5 (7) mottled with dark brown, 6" seam of sand at 15 feet 113 94 21 TV 1.1

272 18 6 - olive brown 59 35

270 20 95 25

7 58 36

268 22

- groundwater encountered at 23.5 feet266 24

264 26 8 (3) SANDY LEAN CLAY (sCL): very soft, olive brown, wet, 90 33 40 15 TV 0.35

gravel at ~26.0 feet262 28 9 97 27

260 30

10 (16) - less sand, stiff 122 95 28 39 20

258 32

256 34

254 36 11 (7) SILTY SAND (SM): loose, olive brown, wet 120 94 28


SAM

PLER

S

ELEV

ATIO

N (F

T)

DEPT

H (F

T)

MAT

ERIA

LSY

MBO

L

SAM

PLE

NO.

PLAS

TICI

TY IN

DEX,

PI

UNDR

AINE

D SH

EAR

STRE

NGTH

(ksf)



SAM

PLER

BLO

WCO

UNT

TOTA

L UN

IT W

T (p

cf)

DRY

UNIT

WT

(pcf

)

WAT

ER C

ONTE

NT (%

)

%PA

SSIN

G #2

00

LIQU

ID L

IMIT

, LL

4


Highland Drive, west road, 5 feet east of path


252 38

250 40

12 (8) SANDY LEAN CLAY (sCL): medium stiff, olive brown, wet248 42

246 44

13 7 - less sand, brown 30 44 21 PP 0.75

244 46 BORING TERMINATED AT 45.5 FEET

242 50

240 52

238 54

236 56

234 58

232 60

230 62

228 64

226 66

224 68

222 70

220 72

218 74


SAM

PLER

S

ELEV

ATIO

N (F

T)

DEPT

H (F

T)

MAT

ERIA

LSY

MBO

L

SAM

PLE

NO.

PLAS

TICI

TY IN

DEX,

PI

UNDR

AINE

D SH

EAR

STRE

NGTH

(ksf)



SAM

PLER

BLO

WCO

UNT

TOTA

L UN

IT W

T (p

cf)

DRY

UNIT

WT

(pcf

)

WAT

ER C

ONTE

NT (%

)

%PA

SSIN

G #2

00

LIQU

ID L

IMIT

, LL

5

6

7

8

9

10

Appendix C – Laboratory Testing

Appendix C includes the following:

C-2: Atterberg Limits

C-7: Incremental Consolidation Results

C-16: Moisture and Density Measurements

C-21: Proctor Compaction

C-22: Swell Test

C-23: Expansion Index

C-26: Unconsolidated Undrained Triaxial Tests

1

2

3

4

5

6

Job No. Job NameLab No. Client

SAMPLE DATASample No. 5B Depth (ft)

Soil DescriptionSample Type

CONSOLIDATION DATA SHEET

CE581-3-14 Highland Parking StructureCal Poly1

Test Method: ASTM D2435

Fat CLAY w ith sand (CH): olive brow n, moistBoring No. DH-1 16.0

Mod. Cal. Shelby Tube Other

0 1 10 100 1000

-5

0

5

10

15

20

0.30

0.40

0.50

0.60

0.70

0.80

Vertical Stress (ksf)

Verti

cal S

trai

n, ε

(%)

Void

Rati

o, e

7


SAMPLE DATASample No. 6 Depth (ft)





Sandy lean CLAY (CL): brow n, moistBoring No. DH-1 18.2


0 0 1 10 100

-5

0

5

10

15

20

25 0.35

0.45

0.55

0.65

0.75

0.85


Verti

cal S

trai

n, ε

(%)

Void

Rati

o, e

8







Lean CLAY w ith sand (CL): brow n, moist, trace gravelBoring No. DH-1 36.0


0 1 10 100 1000

-5

0

5

10

15

20

250.30

0.40

0.50

0.60

0.70

0.80


Verti

cal S

trai

n, ε

(%)

Void

Rati

o, e

9







Lean CLAY (CL): brow n, moistBoring No. DH-1 37.3


0 0 1 10 100

-5

0

5

10

15

20

25 0.32

0.42

0.52

0.62

0.72

0.82


Verti

cal S

trai

n, ε

(%)

Void

Rati

o, e

10


SAMPLE DATASample No. 3A Depth (ft)





Sandy fat CLAY (CH): olive gray, moist, pinhole-sized voidsBoring No. DH-2 8.0


0 1 10 100 1000

-4.15

0.85

5.85

10.85

15.85

20.85

25.85

0.30

0.40

0.50

0.60

0.70

0.80

0.90


Verti

cal S

trai

n, ε

(%)

Void

Rati

o, e

11







Lean CLAY (CL): brow n, moistBoring No. DH-2 16.0


0 1 10 100 1000

-11

-1

10

20

30

40 0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

1.10

1.20


Verti

cal S

trai

n, ε

(%)

Void

Rati

o, e

12







Lean CLAY (CL): soft, brow n, moistBoring No. DH-2 16.5


0 0 1 10 100 1000

-10

-5

0

5

10

15

20

25

30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

1.10

1.20

1.30


Verti

cal S

trai

n, ε

(%)

Void

Rati

o, e

13







Lean CLAY (CL): dark brow n, moist, w ith trace organicsBoring No. DH-2 21.4


0.0 0.1 1.0 10.0 100.0 1000.0

-9.7

-4.7

0.3

5.3

10.3

15.3

20.3

25.3

30.3 0.40

0.50

0.60

0.70

0.80

0.90

1.00

1.10

1.20


Verti

cal S

trai

n, ε

(%)

Void

Rati

o, e

14

Project Name Project No.

Tested By Testing Date

Boring No. DH-1

Sample No. 3A

Sample Depth (ft) 8.0

Group Symbol CL

Estimated Specific Gravity 2.70

Soil Description:

dark

gra

y, m

oist

, with

ir

on o

xide

stai

ning

Number of Rings 4

Mass of Moist Sample + Rings (g) 790.22

Specimen Diameter (mm) 61.01

Specimen Height (mm) 102.31

Total Ring Mass (g) 182.82

Dish ID 101

Mass of Dish (g) 30.82

Mass of Moist Soil + Dish (g) 53.67

Mass of Dry Soil + Dish (g) 49.55

Water Content 22.0% #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Total Density (Mg/m3) 2.031 #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Dry Density (Mg/m3) 1.665 #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Total Unit Weight (lbs/ft3) 126.7 #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Dry Unit Weight (lbs/ft3) 103.9 #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Saturation 95.5% #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Void Ratio 0.62 #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Porosity 0.38 #DIV/0! #DIV/0! #DIV/0! #DIV/0!

DEPARTMENT OF CIVIL AND ENVIRONMENTAL ENGINEERINGMoisture and Density Measurements

Test Methods: ASTM D2488, 2216, 2937

CE 581

Group 1CE581-3-14

5/29/2014

RESULTS

SPECIMEN ID AND CLASSIFICATION

DIMENSIONS AND MASS

WATER CONTENT

15



Boring No. DH-1 DH-1 DH-1 DH-1 DH-1

Sample No. 4 2 5A Bluk A Bulk B

Sample Depth (ft) 10.0 5.0 15.5 2.0 7.0

Group Symbol CH CH CH CH CH

Estimated Specific Gravity 2.70 2.70 2.70 2.70 2.70

Soil Description:

stiff,

bro

wn,

moi

st, i

ron

oxid

e st

aini

ng

stiff,

dar

k br

own,

moi

st

stiff,

ligh

t br

own,

moi

st

brow

n, m

oist

very

stiff

, med

ium

br

own,

moi

st

Number of Rings N/A N/A 5 N/A N/A

Mass of Moist Sample + Rings (g) N/A N/A 981.38 N/A N/A

Specimen Diameter (mm) N/A N/A 60.96 N/A N/A

Specimen Height (mm) N/A N/A 127.00 N/A N/A

Total Ring Mass (g) N/A N/A 227.38 N/A N/A

Dish ID 10 30 223.00 35 93

Mass of Dish (g) 30.81 30.32 30.18 30.81 30.45

Mass of Moist Soil + Dish (g) 62.25 55.46 65.77 78.09 61.88

Mass of Dry Soil + Dish (g) 57.07 49.70 58.43 68.90 56.42

Water Content 19.7% 29.7% 22.6% 24.1% 21.0%

Total Density (Mg/m3) #VALUE! #VALUE! 2.034 #VALUE! #VALUE!

Dry Density (Mg/m3) #VALUE! #VALUE! 1.659 #VALUE! #VALUE!

Total Unit Weight (lbs/ft3) #VALUE! #VALUE! 126.9 #VALUE! #VALUE!

Dry Unit Weight (lbs/ft3) #VALUE! #VALUE! 103.5 #VALUE! #VALUE!

Saturation #VALUE! #VALUE! 97.4% #VALUE! #VALUE!

Void Ratio #VALUE! #VALUE! 0.63 #VALUE! #VALUE!

Porosity #VALUE! #VALUE! 0.39 #VALUE! #VALUE!



Highland Parking Structure

Group 1CE581-3-14

5/15/2014

RESULTS


DIMENSIONS AND MASS

WATER CONTENT

16



Boring No. DH-2 DH-2 DH-2 DH-2 DH-2

Sample No. 1A 2 A (Top of bag) A (Bot of bag) 3A

Sample Depth (ft) 2.5 5.0 6.0 - 9.0 6.0 - 9.0 8.0

Group Symbol GW CH CH CH CH

Estimated Specific Gravity 2.65 2.75 2.75 2.75 2.75

Soil Description:

dens

e, g

ray-

brow

n, d

ry,

dist

urbe

d

med

ium

sti

ff, d

ark

brow

n, d

ry

med

ium

sti

ff, d

ark

brow

n, d

ry

med

ium

sti

ff, d

ark

brow

n, d

ry

stiff,

oliv

e-br

own,

moi

st

Number of Rings N/A N/A N/A N/A 4

Mass of Moist Sample + Rings (g) N/A N/A N/A N/A 759.21

Specimen Diameter (mm) N/A N/A N/A N/A 61.50

Specimen Height (mm) N/A N/A N/A N/A 101.60

Total Ring Mass (g) N/A N/A N/A N/A 174.00

Dish ID B51 19 2 37 101

Mass of Dish (g) 183.12 30.71 30.74 30.82 30.82


Mass of Dry Soil + Dish (g) N/A 98.00 112.64 93.72 87.27

Water Content #VALUE! 26.9% 21.8% 23.8% 22.6%

Total Density (Mg/m3) #VALUE! #VALUE! #VALUE! #VALUE! 1.939

Dry Density (Mg/m3) #VALUE! #VALUE! #VALUE! #VALUE! 1.582

Total Unit Weight (lbs/ft3) #VALUE! #VALUE! #VALUE! #VALUE! 121.0

Dry Unit Weight (lbs/ft3) #VALUE! #VALUE! #VALUE! #VALUE! 98.7

Saturation #VALUE! #VALUE! #VALUE! #VALUE! 84.0%

Void Ratio #VALUE! #VALUE! #VALUE! #VALUE! 0.74

Porosity #VALUE! #VALUE! #VALUE! #VALUE! 0.42

RESULTS


DIMENSIONS AND MASS

WATER CONTENT



CE 581

Group 3CE581-3-14

5/8/2014

17



Boring No. DH-2 DH-2

Sample No. 5B B

Sample Depth (ft) 16.0 11 to 14

Group Symbol SM CH

Estimated Specific Gravity 2.65 2.75

Soil Description:

med

-sti

ff, m

oist

, oliv

e br

own

med

-stu

ff, m

oist

, dar

k br

own

Number of Rings 1

Mass of Moist Sample + Rings (g) 180.57

Specimen Diameter (mm) 61.50

Specimen Height (mm) 25.40

Total Ring Mass (g) 43.50

Dish ID 203 ST-46

Mass of Dish (g) 30.30 100.45

Mass of Moist Soil + Dish (g) 152.22 228.90

Mass of Dry Soil + Dish (g) 130.95 208.09

Water Content 21.1% 19.3% #DIV/0! #DIV/0! #DIV/0!

Total Density (Mg/m3) 1.817 #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Dry Density (Mg/m3) 1.500 #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Total Unit Weight (lbs/ft3) 113.4 #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Dry Unit Weight (lbs/ft3) 93.6 #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Saturation 73.0% #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Void Ratio 0.77 #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Porosity 0.43 #DIV/0! #DIV/0! #DIV/0! #DIV/0!



CE 581

Group 3CE581-3-14

6/29/2014

RESULTS


DIMENSIONS AND MASS

WATER CONTENT

18



Boring No. DH-2 DH-2 x x x

Sample No. 11A 10A x x x

Sample Depth (ft) 26.0 30.0 x x x

Group Symbol CL CL x x x

Estimated Specific Gravity 2.70 2.70 x x x

Soil Description:

Lean

Cla

y (C

L): M

ed

Stuff

, Dar

k Br

own,

Moi

st

Sand

y Le

an C

lay,

Med

Sti

ff, D

ark

Brow

n, M

oist

x x x

Number of Rings 5 3 x x x

Mass of Moist Sample + Rings (g) 954.37 377.56 x x x

Specimen Diameter (mm) 61.50 61.50 x x x

Specimen Height (mm) 127.00 50.80 x x x

Total Ring Mass (g) 217.50 87.00 x x x

Dish ID 47 28 x x x

Mass of Dish (g) 30.75 31.05 x x x

Mass of Moist Soil + Dish (g) 88.53 109.20 x x x

Mass of Dry Soil + Dish (g) 75.76 92.22 x x x

Water Content 28.4% 27.8% #VALUE! #VALUE! #VALUE!

Total Density (Mg/m3) 1.953 1.925 #VALUE! #VALUE! #VALUE!

Dry Density (Mg/m3) 1.522 1.507 #VALUE! #VALUE! #VALUE!

Total Unit Weight (lbs/ft3) 121.9 120.1 #VALUE! #VALUE! #VALUE!

Dry Unit Weight (lbs/ft3) 94.9 94.0 #VALUE! #VALUE! #VALUE!

Saturation 98.9% 94.7% #VALUE! #VALUE! #VALUE!

Void Ratio 0.77 0.79 #VALUE! #VALUE! #VALUE!

Porosity 0.44 0.44 #VALUE! #VALUE! #VALUE!

RESULTS


DIMENSIONS AND MASS

WATER CONTENT



CE 581

Group 4Highland Parking Structure

5/8/2014

19



Boring No. DH-2

Sample No. 13

Sample Depth (ft) 44.0

Group Symbol CL

Estimated Specific Gravity 2.70

Soil Description:

Lean

Cla

y

Number of Rings NA

Mass of Moist Sample + Rings (g) NA

Specimen Diameter (mm) NA

Specimen Height (mm) NA

Total Ring Mass (g) NA

Dish ID 90

Mass of Dish (g) 30.72

Mass of Moist Soil + Dish (g) 102.97

Mass of Dry Soil + Dish (g) 86.45

Water Content 29.6% #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Total Density (Mg/m3) #VALUE! #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Dry Density (Mg/m3) #VALUE! #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Total Unit Weight (lbs/ft3) #VALUE! #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Dry Unit Weight (lbs/ft3) #VALUE! #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Saturation #VALUE! #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Void Ratio #VALUE! #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Porosity #VALUE! #DIV/0! #DIV/0! #DIV/0! #DIV/0!

RESULTS


DIMENSIONS AND MASS

WATER CONTENT



CE 581

Group 414.581.1

5/22/2014

20



Boring No. DH-1 Sample No. A Depth (ft) 2'-4'

Soil Description

Test Method (D698/D1557) D1557 Ram. Mass (g) 4534 # of Lifts 5Mold Volume (cm3) 943 Mold Mass(g) 1986 Blows/ Lift 25

Mass of Soil + Mold (g) 3869 3810 3905 3966 3661

Dish ID 83 14 2 201 85

Mass of Dish (g) 30.46 31.10 30.73 30.37 30.44


Mass of Dry Soil + Dish (g) 40.40 38.53 40.14 46.13 60.72

Water Content 23.3% 27.9% 20.6% 18.4% 16.5%

Dry Density (Mg/m3) 1.619 1.513 1.687 1.773 1.525 Water Content (%) Lab Max. Dry Density (Mg/m3) 18.5% 27.9%

23.3%20.6%18.4%16.5%

EQUIPMENT AND PROCEDURE

DEPARTMENT OF CIVIL AND ENVIRONMENTAL ENGINEERINGProctor Compaction

Test Method: ASTM D698, D1557

Highland Parking Structure CE 581Group 1 5/22/2014


Fat CLAY (CH): dk. brown, moist

DENSITY AND MOISTURE MEASUREMENTS

RESULTS

1.775 Optimum Water Content (%)

1.40

1.50

1.60

1.70

1.80

1.90

2.00

2.10

2.20

2.30

2.40

2% 6% 10% 14% 18% 22% 26% 30%

Dry

Dens

ity (M

g/m

3 )

Water Content (%)

Moisture Density Relationship

Compaction Curve

ZAV Curve (Gs=2.7)

21

22


SAMPLE DATASample No. A Depth (ft)


Node ID #: -- Cell ID #: ICON 2

212 233

30.36 29.8586.12 93.38 Target, psf Actual, g78.57 82.15 1 100 150 0.0000015.7% 21.5% 2 1,380 2,000 0.01350

3 1,380 2,000 -0.00835456789

10111213141516

17181920212223

0.789 0.789 24252627282930

Tested By Date Checked By

138.54




Mass of Sample+Ring (g)

Fat CLAY (CH): dark brow n, moist

Remold

Boring No. DH-1 2-4

PRELIMINARY RESULTS TESTING INFORMATION

43.01

Void Ratio 0.93

Height Meas/Calc'd (in)

125.82

Specif ic Gravity 2.7

Moisture Tare I.D

Saturation (%) 94.6%

32.6%

Wet Mass + Tare (g) Dry Mass + Tare (g)

Tare Mass (g)

Mass of Ring (g)

Moisture Tare I.D

ND/GF

Equiv. Height of Solids, in 0.408 Volume of Solids, in3 1.878 Dry Mass of Spec. (g) 83.11

Height, H4 (in) 0.784

Dry Unit Weight (pcf) 88.2

Initial Moisture (%) 14.9%

Void Ratio 0.91 Porosity (%) 47.7%

44.3%

Mass of Ring (g) 43.01

Wet Mass + Tare (g)

ND

Average Height (in)

Saturation (%)

0.780

102.73ST-51


FINAL RESULTS153.23

Tare Mass (g)

5/29/2014


Dry Mass + Tare (g) 120.14 Moisture Content (%)

Moisture Content (%)

0.787 Height, H3 (in)

Height, H1 (in) 0.776 Diameter (in) 2.420


Sample Stress Final Disp, in

CONSOLIDATION LOADING SCHEDULE

Step


23




Node ID #: -- Cell ID #: Icon 1

28 223

31.04 30.1839.35 41.88 Target, psf Actual, g38.26 40.37 1 100 150 0.0000015.1% 14.8% 2 2,760 4,000 0.01705

3 2,760 4,000 0.03935456789

10111213141516

17181920212223

0.697 0.697 24252627282930


133.36






Remold

Boring No. DH-1 2-4


45.18

Void Ratio 0.86


128.69


Moisture Tare I.D


30.9%


Tare Mass (g)

Mass of Ring (g)

Moisture Tare I.D

ND/GF






43.2%


Wet Mass + Tare (g)

ND

Average Height (in)

Saturation (%)

0.737

101.81ST-38


FINAL RESULTS145.27

Tare Mass (g)

5/29/2014









Step


24




Node ID #: -- Cell ID #: Icon 3

68

30.6137.77 Target, psf Actual, g36.80 1 100 150 0.0000015.7% %MC2 2 100 150 -0.10370

345678910111213141516

17181920212223

0.867 0.867 24252627282930


136.40






Remold

Boring No. DH-1 2-4


42.88

Void Ratio 1.17


129.81


Moisture Tare I.D


38.9%


Tare Mass (g)

Mass of Ring (g)

Moisture Tare I.D

ND/GF






45.0%


Wet Mass + Tare (g)

Average Height (in)

Saturation (%)

0.763

100.61ST-1


FINAL RESULTS155.62

Tare Mass (g)









Step


25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

Appendix D –Calculations

Appendix D includes the following:

D-2: Shear Wave and Modulus

D-3: Consolidation and Settlement

D-6: Deep Foundation Axial and Corrected Blow Counts

1

This is a sample consolidation graph. The data is from DH-2 3A 8.0ft. We used the Casagrande procedure to find maximum past pressure (6800psf) and got an OCR value of 7. This means the sample is highly overconsolidated, so we constructed the virgin compression curve to get Cc and Cr using the Schmertmann procedure. The following page has hand calculations of these values. This same procedure was performed on all of the consolidation curves from Appendix C to get Cc and Cr values.

3

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