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    PAGE NO. 2 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    TABLE OF CONTENTS

    1.0 SCOPE

    2.0 DEFINITIONS

    3.0 CONFLICTS AND DEVIATIONS

    4.0 GENERAL AND SAFETY REQUIREMENTS

    4.1 General Requirements

    4.2 Safety Requirements

    5.0 CODES ANDSTANDARDS

    5.1 Company Standards

    5.2 International Standards

    6.0 CLEARING SITE AND ROUGH GRADING

    6.1 Clearing of Existing Materials and Miscellaneous Fill Materials

    6.2 Rough Grading

    7.0 EXCAVATION

    7.1 General

    7.2 Excavation for Buildings and Structures

    7.3 Utility Trenching

    7.4 Bracing and Shoring

    8.0 DEWATERING

    8.1 Groundwater

    8.2 Surface Runoff

    9.0 SELECTION AND TYPES OF CONTROLLED FILL MATERIALS

    9.1 Types of Controlled Fill

    9.2 Requirements of Controlled Fill Materials

    9.3 Acceptance of Controlled Fill Materials

    10.0 CONSTRUCTION REQUIREMENTS

    10.1 Sub-grade10.2 Backfill

    10.3 Embankments

    10.4 Test Section for Embankments

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    PAGE NO. 3 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    11.0 SLOPE PROTECTION

    11.1 Permanent Slopes

    11.2 Temporary Slopes

    12.0 SABKHAH SOILS

    12.1 General

    12.2 Improvement of Sabkhah Soils

    12.3 Drainage Control

    13.0 QUALITY CONTROL, INSPECTION AND REPORTS

    13.1 Quality Control and Inspection

    13.2 Reports

    14.0 FINAL GRADING AND CLEANUP

    15.0 BIBLIOGRAPHY AND APPENDICES

    15.1 Bibliography

    15.2 Appendices

    16.0 FIGURES

    Figure 1 - Slope Protection for Foundation

    Figure 2 - Utility Trench

    Figure 3 - Dewatering Scheme

    Figure 4 - Gutter Isometric View - Slope Protection

    Figure 5 - Gutter Longitudinal Section - Slope Protection

    Figure 6 - Gutter Section A-A - Slope Protection

    Figure 7 - Soil Particles Sizes for Ground Improvement Techniques

    Figure 8 - Approximate correlation of soil ratings base on CBR values for use in

    pavements.

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    PAGE NO. 4 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    1.0 SCOPE

    This Transmission Construction Standard covers the mandatory requirements for the

    construction of safe and reliable facilities by controlling earthwork in the system of Saudi

    Electricity COMPANY (SEC). This Standard is applicable for all the works for the

    COMPANY including, but not limited to, the following:

    a. Clearing site and rough grading

    b. Excavation

    c. Bracing and shoring

    d. Dewatering

    e. Selection of fill materials

    f. Preparation and compaction of existing sub-grade

    g. Backfilling

    h. Construction of embankment

    i. Slope protection

    j. Developing Sabkhah Area

    k. Final grading and cleanup

    2.0 DEFINITIONS

    2.1 Backfill Refers to the construction of earth fill in confined spaces, such as therefilling operations above concrete structures, or refilling in trenches

    around pipes, direct buried cables, etc.

    2.2 Base course The layer or layers of specified or selected material of designed

    thickness placed on a sub-base or sub-grade to support surface course

    such as asphalt concrete, aggregate surfacing or concrete pavement

    2.3 Borrow Pit A site where earth material is removed by mechanical equipment and

    transported to an off-site location for use in grading

    2.4 Borrow Pit Boundary: The boundary for a Borrow Pit is defined in the Borrow Pitpermit

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    PAGE NO. 5 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    2.5 Controlled Fill This is defined as the placement of earthfill of specified engineering

    properties (gradation, plasticity index, California Bearing Ratio,

    thermal conductivity, etc.) and compacted to a required density.

    2.6 Existing grade Existing grade is the grade prior to grading

    2.7 Fill Fill is a deposit of earth material placed by artificial means

    2.8 Finished grade Finished grade is the final grade of the site, which conforms to the

    approved plan by the COMPANY.

    2.9 Grade Grade shall mean the vertical location of the ground surface

    2.10 Grade Slope Refers to cut and fill side slope as per site requirements or as indicatedin the approved drawings. Standard for Cut=1:2 (vertical: horizontal)

    and for Fill = 1:4. Berming system is also applicable for cut slope.

    2.11 Grading Leveling at site any excavation, filling or a combination thereof

    2.12 Rough Grade Refers to grading the construction site to approximate design contours

    2.13 Select Fill Materials, obtained from a specified source such as a borrow area, of

    acceptable quality having a specified characteristic to be used for a

    specific purpose. The material, if not of acceptable quality, shall be

    improved by mixing at site with suitable material to meet the specifiedcharacteristics such as gradation, CBR, plasticity index, etc.

    2.14 Sub-base The layer or layers of specified or selected material of designed

    thickness placed on a sub-grade to support a base course

    2.15 Sub-grade The existing underlying ground prepared and compacted for

    supporting foundations of structures, embankments, pavements, etc.

    3.0 CONFLICTS AND DEVIATIONS

    3.1 Any conflicts between this Standard and other applicable Saudi Electricity Company

    (SEC) Standards, Industry Standards, Codes, and forms shall be resolved in writing

    by the COMPANY Representative.

    3.2 Any request to deviate from this Standard shall be directed to the Manager of

    Transmission Standards and Specifications.

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    PAGE NO. 6 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    4.0 GENERAL AND SAFETY REQUIREMENTS

    4.1 General Requirements

    4.1.1 All works performed and all materials furnished shall be in conformity with

    the lines, grades, cross-sections, dimensions, and material requirements,

    including tolerances, shown on the plans/drawings or indicated in the

    specifications.

    4.1.2 All materials to be incorporated into the work shall meet or exceed the

    appropriate AASHTO, ASTM, or other Standard and specifications as

    required by the plans/drawings and specifications but in no case shall be less

    than the requirements of this Standard.

    4.1.3 All materials shall be inspected, sampled, tested and accepted by the

    COMPANY Representative before incorporation into the work.

    4.1.4 Field and laboratory tests required to determine compliance with the

    compaction requirements of this Standard shall be done by an Independent

    Agency approved by the COMPANY.

    4.1.5 No material, regardless of its source, shall be incorporated in the Work until

    representative samples taken and tested by the SEC approved Independent

    Laboratory have been reviewed and approved by the COMPANYRepresentative.

    4.1.6 Sub-grades or bottom of excavation for structures shall be firm, dense and

    thoroughly compacted as specified under Construction Requirements. It shall

    be free from mud and muck, and sufficiently stable to remain firm and intact

    under the feet of the workmen.

    4.1.7 Adequate dewatering equipment to remove and dispose all surface and

    groundwater entering the excavations and other parts of the work, shall be

    provided at site and maintained properly.

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    PAGE NO. 7 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    4.2 Safety Requirements

    4.2.1 The safety provisions of Construction Safety Manual (Appendix I) shall be

    strictly followed.

    4.2.2 Excavation by the use of explosives shall be with prior written approval from

    the SEC.

    4.2.3 The stability of adjacent structures or facilities including public safety shall

    not be impaired or endangered by excavation works.

    4.2.4 All existing underground utilities, which may be uncovered or otherwise be

    affected by the excavation work shall be properly protected, by shoring,bracing, and supporting, etc., as needed.

    5.0 CODES ANDSTANDARDS

    The latest revisions/amendments of the following Standard and specifications are intended as

    guidance in providing an acceptable level of quality and practice. In case of conflict between

    these Standards and the text of this Standard, the latter shall govern:

    5.1 COMPANY Standards

    5.1.1 TCS-P-104 Underground High Voltage Cable Installation Standards

    5.1.2 TCS-Q-113.01 Asphalt Concrete Paving

    5.1.3 TCS-Q-113.03 Cast-In-Place Concrete

    5.1.4 TES-P-122.11 Access Roads and Structure Pads

    5.1.5 TES-S-130 General Procedures/Safety Standards for Blasting nearSEC Facilities

    5.2. International Standards

    5.2.1 ASTM C 127 Test Method for Density, Relative Density (Specific

    Gravity) and Absorption of Coarse Aggregates

    5.2.2 ASTM D 421 Practice for Dry Preparation of Soil Samples for Particle-

    Size Analysis and Determination of Soil Constants

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    PAGE NO. 8 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    5.2.3 ASTM D 422 Method for Particle-Size Analysis of Soils

    5.2.4 ASTM D 698 Test Methods for Laboratory Compaction Characteristics

    of Soil (Moisture-Density Relations) Using Standard Effort

    (12,400 ft-lbf/ft3(600 kN-m/m3))

    5.2.5 ASTM D 854 Test Methods for Specific Gravity of Soil Solids by

    Pycnometer

    5.2.6 ASTM D 1194 Test Method for Bearing Capacity of Soil for Static Load

    and Spread Footings

    5.2.7 ASTM D 1556 Test Method for Density of Soil in place by the Sand-ConeMethod

    5.2.8 ASTM D 1557 Test Method for Laboratory Compaction Characteristics of

    Soil Using Modified Effort (56,000 ft-lbf/ft3 (2,700 kN-

    m/m3))

    5.2.9 ASTM D 1558 Test Method for Moisture Content Penetration Resistance

    Relationships of Fine-Grained Soils

    5.2.10 ASTM D 1586 Test Method for Penetration Test and Split Barrel

    Sampling of Soils

    5.2.11 ASTM D 1632 Practice for making and Curing Soil-Cement Compression

    and Flexural Test Specimens in the Laboratory

    5.2.12 ASTM D 1633 Test Method for Compressive Strength of Moulded Soil-

    Cement Cylinders

    5.2.13 ASTM D 1739 Test Method for Collection and Measurement of Dustfall

    (Settleable Particulate Matter)

    5.2.14 ASTM D 1883 Test Method for CBR (California Bearing Ratio) of

    Laboratory-Compacted Soils

    5.2.15 ASTM D 2216 Test Method for Laboratory Determination of Water

    (Moisture) Content of Soil and Rock by Mass

    5.2.16 ASTM D 2922 Test Methods for Density of Soil and Soil-Aggregate in

    Place by Nuclear Methods (Shallow Depth)

    5.2.17 ASTM D 4253 Test Methods for Maximum Index Density and UnitWeight of Soils Using a Vibratory Table

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    PAGE NO. 9 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    5.2.18 ASTM D 4254 Test Methods for Minimum Index Density and UnitWeight of Soils and Calculation of Relative Density

    5.2.19 ASTM D 4318 Test Methods for Liquid Limit, Plastic Limit, and Plasticity

    Index of Soils

    5.2.20 ASTM D 4791 Test Method for flat particles, elongated particles, or flat

    particles and elongated particles in coarse Aggregate

    5.2.21 AASHTO T-180 Test Method for Moisture-Density Relations of Soils Using

    a 4.54 kg (10-lb) Rammer and 457 mm (18-in.) Drop

    6.0 CLEARING SITE AND ROUGH GRADING

    6.1 Clearing of Existing Materials and Miscellaneous Fill Materials

    6.1.1 The site shall be cleared of all boulders, debris, decomposable materials such

    as wood, grass, plants, tree stumps, etc., to the satisfaction of COMPANY

    Representative.

    6.1.2 All existing miscellaneous fill, broken building materials, or damaged

    concrete shall be removed from the area.

    6.1.3 Where structural support is required, the soil that softens due to rainfall,

    groundwater, disturbance, exposure or any other cause shall be excavated and

    replaced with controlled fill.

    6.1.4 Burning of rubbish and organic materials, resulting from the site clearing

    operations, shall not be permitted on the site or adjacent property.

    6.1.5 All surplus materials, resulting from the site clearing operations, shall be

    transported to and dumped in municipal approved dump areas, with priorapproval from the COMPANY Representative

    6.1.6 Care shall be taken to protect existing utilities, site improvement works and

    existing structures.

    6.2 Rough Grading

    Rough grading shall be done to the approximate finished lines and grades shown on

    approved drawings. This area shall then be inspected and approved by the

    COMPANY Representative before commencing any work.

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    PAGE NO. 10 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    7.0 EXCAVATION

    7.1 General

    7.1.1 Prior to excavation, information about all existing underground services such

    as gas, water, telephone lines, sewage lines, electric cables, etc., shall be

    obtained from ministries, municipalities, utility companies and other affected

    agencies. Excavation shall be carried out with special care and with proper

    permissions to avoid any interference with these systems. Only manual

    excavation shall be employed in locations where underground utilities are

    present. Any damage caused shall be repaired expeditiously and restoration of

    services shall be made without delay.

    7.1.2 Safe working distances and overhead clearances shall be maintained at all

    times when working near or under energized overhead lines or substation

    structures to ensure safety of personnel and avoid accidental disruption of

    power. Safe working distance shall be in accordance with Chapter 14 of

    Construction Safety Manual (See Appendix II).

    Work permits shall be secured prior to excavation in locations classified as

    restricted areas such as inside substations, power plants, and near or under

    overhead power lines.

    7.1.3 Subject to permission from concerned agency of Saudi Arabian Government,any blasting in the proximity of facilities shall be approved by the SEC as per

    TES-S-130, General Procedures/Safety Standards for Blasting near SEC

    facilities. The danger of damage to existing structures shall be minimized by

    limiting velocity, induced in any structure due to ground motions created by

    blasting to a maximum of 50 mm/sec. No blasting shall be permitted in the

    vicinity of concrete within 7 days of its placement.

    Blasting shall be controlled to avoid injury to human beings, damage to

    adjacent structures and shattering or weakening of the rock below foundation

    level. All blasting shall conform to the local and government regulations.

    7.1.4 Excavation in all types of soil and rock shall be treated as unclassified

    excavation.

    7.2 Excavation for Buildings and Structures

    7.2.1 Excavation Limits for Structures

    Pits and trenches shall be excavated to grades and depths shown on the

    approved drawings. Trenches and pits in loose earth shall be at least 300 mm

    bigger in both plan dimensions than the size of foundations. Trenches andpits for footings in stiff cohesive material or rock shall not be wider than

    necessary for formwork and bracing.

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    PAGE NO. 12 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    Also, special trenching and backfilling requirements of the Government

    agencies (Ministries, Municipalities), having jurisdiction, shall apply.

    7.3.2 Utility trenching shall follow strictly the approved alignment requirements.

    Care shall be taken such that pipes, cables, and duct runs shall be made as

    straight as possible, both horizontally and vertically, and if a deflection must

    be made, it shall be along a smooth and gradual curve to avoid stressing the

    ducts, cables or pipes.

    7.3.3 All excavations shall be extended at least 150 mm below the bottom of pipe

    or power cable to provide an all around 150 mm minimum clean sand bedding

    (See Figure 2). The gradation of clean sand shall conform to Section 9.1.3.

    The thermal conductivity of sand around power cables shall comply with

    design requirements.

    7.3.4 Trenches shall be excavated to the grade shown on the profile with a

    minimum of 1000 mm and 500 mm earth cover over the top of the service line

    in traffic areas and non-traffic areas, respectively (See Figure 2). Excess

    excavation below required level shall be backfilled with selected fill materials

    compacted to 95% of the maximum density as determined by ASTM D 1557

    for soils containing more than 15% material passing the 75-micron sieve or

    85% relative density (ASTM D 4253 and ASTM D 4254) for free draining

    cohesionless soils containing less than 15% non-plastic material passing 75-

    micron sieve.

    7.3.5 Soft or loose spots in the trench shall be compacted to the density as per

    Section 7.3.4 or the soft materials shall be removed and replaced with selected

    fill materials that is compacted to the density per Section 7.3.4.

    7.3.6 The trench bottom shall be continuous, smooth and free of loose debris and/or

    sharp rocks which could damage the service line/power cable.

    7.4 Bracing and Shoring

    7.4.1 The sides of pits and trenches shall be sloped back to the natural angle ofrepose of the soil to avoid caving. Sides which cannot be sloped, because of

    space limitation due to adjacent structures, or unrestrained sand masses (loose

    sand) shall be shored adequately to resist earth movement, protect workers,

    and protect on-going work and existing property.

    7.4.2 Shoring shall not be braced against forms. Forms shall be properly braced and

    tied together, independent of shoring.

    7.4.3 Excavated soils, construction materials, or heavy machineries shall not be

    placed at the top of excavations or embankments unless they are set back at a

    previously established safe distance from the top of excavation.

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    PAGE NO. 13 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    8.0 DEWATERING

    8.1 Groundwater

    When it is required to excavate below Ground Water Table (GWT), a suitable

    dewatering system shall be provided to keep the excavated area dry. Sheet piling may

    be required for deep excavations. It will be important to maintain the bottom stability

    of excavations by sheeting and dewatering. Appropriate shoring shall be installed and

    dewatering done to lower the GWT to a depth of approximately 1.0 m below the

    maximum depth of excavation (See Figure 3).

    In order to obtain a stable bottom of the excavation, dewatering should be carried out

    in advance of excavation. Dewatering shall be performed by carefully installed wellpoint system which should be properly designed, having sufficient knowledge of

    local condition. The problem of bottom heave can be anticipated by adopting a

    designed dewatering system. A typical dewatering procedure could be as follows:

    Excavate to near the anticipated ground level. The sides may be supported by sheet

    piles.

    Install well points around the perimeter of the area to be excavated.

    The well points could be jetted or drilled into position. The well points should extend

    below the excavation to a depth of at least about 1.5 times the excavation depthbelow the ground water level. The well points should be spaced about two meters

    center to center (other depth-spacing criteria may be adopted to suit the field

    conditions).

    Dewatering should be accomplished by pumping from the well points. After

    dewatering, excavate the remaining soils to the final grade. Supplemental well points

    may be necessary to lower ground water levels below the bottom of the interior of the

    excavation.

    Typical grain size distribution range of the soils encountered at the study area or fromthe gradation charts shall be obtained. This should assist in the design of a well point

    system, the size of the screening, the sand filter and the size of the vacuum pump, if

    necessary.

    8.2 Surface Runoff

    Grading in the vicinity of excavations shall be controlled to prevent surface water

    running into excavated areas. Any water accumulated in the excavations shall be

    removed by pumping or by other means as approved by the COMPANY

    Representative.

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    PAGE NO. 14 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    9.0 SELECTION AND TYPES OF CONTROLLED FILL MATERIALS

    Controlled fill shall be free of organic matters, rubbles, cobbles and boulders, and other

    deleterious substances.

    9.1 Types of Controlled Fill

    The following four (4) types of controlled fills are classified for earthworks.

    9.1.1 General Fill (Class D) shall meet the following gradation requirements:

    a. Maximum particle size = 100 mm

    b. Between 80% and 40% by weight passing the 2.0 mm mesh sieve

    c. Not more than 15% by weight passing the 75 micron mesh sieve; less

    than 4 plasticity index. Where binding effect is required between soil

    particles as in uncontained embankments, a maximum of 20% by

    weight material passing the 75 micron mesh sieve shall be provided.

    9.1.2 Select Fill shall be a well graded granular material as shown in Table-I.

    Table-I

    USA Standard Sieve

    Size (mm)

    Percent Passing

    50 100

    19.0 95 to 80

    2.0 80 to 50

    0.250 50 to 25

    0.075 20 to 5

    Where free draining properties of the controlled fill are essential, such as

    groundwater table being within 1.5 m depth below the bottom of foundations

    or pavements, the material passing the 75 micron mesh sieve shall be between

    5% and 10% by weight. Where groundwater is not a problem and binding

    effect is required between soil particles, as in uncontained embankments and

    surfaces exposed to erosion, near maximum limit of 20% by weight material

    passing the 75 micron mesh sieve shall be provided.

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    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    9.1.3 Clean sand satisfying the following USA Standard sieve size gradation shall

    be used for bedding around utilities as shown in Table II.

    Table II

    USA Standard Sieve Size (mm) Percent Passing

    4.75 100

    2.00 95 to 80

    0.425 80 to 40

    0.250 60 to 20

    0.075 Less than 10

    9.1.4 Aggregate sub-base and base course materials shall meet the following

    gradation as shown on Table III and physical properties as shown on Table

    IV.

    Table III GRADATION

    Sub-base Material Classes Base Course Material Classes

    CLASS A CLASS B CLASS C CLASS A CLASS BSieveSize

    (mm)

    Well graded

    gravel with

    sand & silt

    Uniform mixture of

    gravel and/ or stone

    fragments with

    sand, silt and clay

    Well

    graded

    sand gravel

    Mixture of all

    aggregate

    uniformly graded

    from coarse to fine

    Uniform

    mixture of

    crushed rock or

    crushed gravel

    101.6 - - - - -

    63.5 100 - - 100 -

    50.8 90 - 100 100 - 90 - 100 -

    38.1 - 70 - 100 100 60 - 90 100

    25.4 - 55 - 85 - 42 - 77 60 - 100

    19.0 * - 50 - 80 - 35 - 70 55 - 85

    12.7 - - - 25 - 60 -9.51 - 40 - 70 - - -

    4.76 35 - 70 30 - 60 - 15 - 40 35 - 60

    2.00 - 20 - 50 80 max. 10 - 26 25 - 50

    0.425 - 10 - 30 - 5 - 15 15 - 30

    0.250 - - - - -

    0.075 0 - 15 5 - 15 15 max. 2 - 9 8 - 15

    * If less than 30% of the sample is retained on a 19 mm sieve, Moisture-Density Relations of

    soils shall be tested in accordance with ASTM D1557, Method C. If the retained sample on a

    19 mm sieve is 30% or more, tests shall be as per AASHTO T-180, Method D

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    PAGE NO. 16 of 46TCSQ11302R0/SZA

    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    TABLE IV PHYSICAL PROPERTIES

    Sub-base Material Base Course Material

    PHYSICAL

    REQUIREMENTSCLASS

    A

    CLASS

    B

    CLASS

    C

    CLASS

    A

    CLASS

    B

    Liquid Limit (Max %) - 25 25 - 25

    Plasticity Index (Max %) - 6 6 6 4-8

    Sand Equivalent (Min %) 25 25 25 30 50

    Loss by abrasion (Max %) 50 50 50 40 40

    Thin and elongated pieces, by

    weight (larger than 25 mm,

    thickness less than 1/5 length)

    as per ASTM D 4791

    (Max %)

    - - - 5 5

    Friable Particles (Max %) - - - 0.25 0.25

    18 18 18 18 18

    Soundness Test using MgSO4(Max. %)

    Coarse Aggregate

    Fine Aggregate

    20 20 20 20 20

    9.2 Requirements of Controlled Fill Materials

    The COMPANY Representative shall approve the depth of the fill after the

    availability of soil reports. Aggregate sub-base and base courses, if specified, shallbe used as fill material for access roads, substation yards, designated roadways,

    parking lots, and material yards where heavy traffic load is expected.

    Controlled Fill materials shall be required up to 1.0 m of the bottom elevation of

    foundations, concrete sidewalks/pavements, slabs on grade, and asphalt concrete

    surface/binder courses depending on the existing sub-grade soil condition.

    Minimum depth of filling shall be 600 mm if the bottom of excavation reveals good

    soil/ hard surface.

    Sand shall be used for bedding around service lines such as pipes, conduits, andcables. In all other instances, General Fill shall be used as sub-base unless

    otherwise specified.

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    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    9.3 Acceptance of Controlled Fill Materials

    Fifty kilogram bag samples of each material to be used as controlled fill shall be

    collected in the presence of COMPANY Representative and submitted for testing to

    an independent soil testing laboratory, approved by the COMPANY, at least ten

    (10) days prior to commencing controlled fill operations. The testing laboratory

    shall perform at least one of each of the following tests on fill samples and submit

    the test results to the COMPANY.

    i. Mechanical analysis (Gradation), ASTM D 422

    ii. Plasticity Index, ASTM D 4318

    If the results from the above tests meet the specification requirements, the testing

    laboratory shall determine the CBR, Sulphate and chloride content including the

    compaction characteristic of the fill material by conducting one of the following tests

    (item a or b below) that is applicable to the gradation, plasticity and drainage

    characteristics of the fill material:

    a. Modified Compaction, ASTM D 1557, Method D, Minimum of Five

    Moisture Density Determinations per Test for soils containing more than

    15% materials passing the 75 micron sieve; or

    b. Maximum and Minimum Index Density of Soils and Calculation of RelativeDensity, ASTM D 4253 and D 4254 for free draining soil containing less

    than 15% non-plastic materials passing the 75 micron sieve.

    c. The California Bearing Ratio (CBR) for each class of fill materials

    compacted in the laboratory after four (4) days soaking as determined by

    ASTM D 1883 shall be as follows:

    Table V

    Material Class CBR Values

    Class A, B, C Not less than 50

    Sub-base Class D (General Fill) Not less than 15

    Base Course Class A & B Not less than 100

    Note: The correlation of the soil ratings based on CBR values is given in

    Figure 8.

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    d. The Sulfate and chloride contents of controlled fill for each class of fill

    materials shall also be determined. Borrowed fill with greater Sulfate orchloride content than the existing soil in the site shall not be used as

    controlled fill for improvement of existing facility.

    No material shall be used as a controlled fill until it is tested, as above, by the

    soil testing laboratory, and approved by the COMPANY Representative.

    Changes in the controlled fill material may be made when characteristics of

    materials, job conditions, weather, test results or other circumstances warrant.

    Each time, a change in fill material has to take place, the new material shall

    be tested as above and test results submitted to COMPANY Representative

    for approval and acceptance before using in the work. A change in controlledfill material and related tests shall be planned so as to avoid construction

    delays.

    Final acceptance of controlled fill material rests with the COMPANY

    Representative, whose decision shall be final and binding.

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    10.0 CONSTRUCTION REQUIREMENTS

    10.1 Sub-grade

    10.1.1 The existing ground surface shall be proof-rolled by the same equipment that

    will be used to compact the controlled fill materials prior to the placement of

    first lift of controlled fill (sub-base). Compaction of the sub-grade may be

    facilitated by maintaining its moisture content at or slightly wet or dry (2 %)

    of the optimum moisture content determined from laboratory tests.

    Depending on the type of structure supported, sub-grade shall be compacted

    to develop the following degrees of compaction to about 300 mm below the

    ground surface:

    Table-VI Compacted Density Requirements of Soils for Different Works

    Type of Supported Structure Degree of Compaction Required

    Service Lines, Concrete Slabs,

    and parking areas

    Minimum of 75% Relative density (ASTM D 4253

    and ASTM D 4254) for free draining soils

    containing less than 15% by weight finer than 75

    micron sieve non plastic material or 90% of the

    maximum density as determined by ASTM D 1557

    for soils containing more than 15% material passingthe 75 micron sieve.

    Light Traffic Road, e.g., Plant

    roads for operations and

    maintenance only and not

    frequently subjected to traffic.

    service lines/ power cables

    below these roads

    Minimum of 80% relative density (ASTM D 4253

    and ASTM D 4254) for free draining soils

    containing less than 15% by weight finer than 75

    micron sieve non plastic material or 92% of the

    maximum density as determined by ASTM D 1557

    for soils containing more than 15% materials

    passing the 75 micron sieve.

    Foundations of all facilitiesincluding buildings,

    transformers, circuit breakers,

    etc, heavy traffic roads carrying

    high density of heavy trucks and

    equipment.

    Minimum of 85% relative density (ASTM D 4253and ASTM D 4254) for free draining soils

    containing less than 15% by weight finer than 75

    micron sieve non plastic material or 95% of the

    maximum density as determined by ASTM D 1557

    for soils containing more than 15% material passing

    the 75 micron sieve

    Service lines or power cables

    below ministry and municipality

    roads

    In addition to above, technical requirements of the

    concerned Ministry or Municipality shall govern.

    Note: ASTM D 2922 can be used for testing the compaction of the soil at site if

    permitted by the COMPANY Representative, provided the soil is uniform.

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    The compaction of the sub-grade or excavation shall be checked and

    approved by the COMPANY Representative before the sub-grade is coveredup with further construction such as sub-base/base course or concrete

    foundation.

    Where soft or otherwise unacceptable zones are disclosed, they shall be

    removed and replaced with approved controlled fill materials compacted as

    discussed above.

    10.1.2 In case of filling Sabkhah or areas of high water table, the requirements for

    proof-rolling the ground surface may be waived by the COMPANY

    Representative if proof-rolling is not feasible. For modification to Sabkhahs,

    refer Section 12.0. Dewatering shall be done for areas of high water table.

    10.1.3 Hand or mechanical tampers shall be used in places inaccessible to rollers.

    10.2 Backfill

    10.2.1 All formworks shall be completely removed but in no case less than 24 hours

    after placing concrete. All debris shall be cleaned out and permission to

    backfill shall be secured from the COMPANY Representative.

    10.2.2 Trenches, pits and other excavations shall be backfilled with materials

    described in Section 9.1. The location of each type of fill shall be governedby Section 9.2. As far as possible, excavated materials shall be used as

    backfill provided they meet the requirements of controlled fill specified in

    this Standard.

    10.2.3 Unless directed otherwise by COMPANY Representative, backfill adjacent

    to or against any structural concrete shall not be placed until the concrete in

    the adjacent structure has attained a minimum of 75% of its design strength

    and is coated with coal tar epoxy.

    10.2.4 Backfill materials shall be placed in uniform layers not exceeding 300 mm ofuncompacted thickness. Increased thickness may be permitted for non-

    cohesive materials by the COMPANY representative if the specified

    compacted density can be obtained.

    10.2.5 Unless specified otherwise, backfill shall be compacted to densities indicated

    in Table VI at or slightly wet or dry ( 2 %) of optimum moisture content.

    10.2.6 Where controlled fill is placed adjacent to walls, which are not designed as

    retaining walls, either the difference in elevation of the top of the controlled

    fill on both sides of the wall shall not be more than 300 mm, or the wall is to

    be adequately braced.

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    10.2.7 All utility lines shall be laid on a clean sand bed compacted to the density

    criteria of Table VI. Sand shall conform to Section 9.1.3 and thermalresistivity of sand around power cables shall comply with design

    requirements. After utility lines have been laid, clean sand shall be carefully

    placed and compacted beneath the bottom half of the service lines to assure

    firm support. Careful backfilling and compaction by tamping or inundation

    with water shall continue above the service lines.

    10.2.8 Finished grades adjacent to structures shall slope away from the structures to

    minimize ingress of precipitation and quickly drain away the surface runoff.

    10.3 Embankments

    10.3.1 Prior to placing the first layer of controlled fill, sub-grade shall be leveled, if

    necessary moistened, compacted, tested and then scarified so that the surface

    material of the sub-grade is as compact and well bonded with the first layer of

    controlled fill as is specified for succeeding layers of controlled fill. Test

    criteria for the sub-grade shall be as per Section 9.3. Bond between a sloping

    sub-grade and controlled fill shall be improved by benching the sub-grade.

    10.3.2 Unless otherwise specified, all controlled fill shall conform to soil gradation

    specified in Section 9.1. The location of use of each type of controlled fill

    shall be determined by provisions of Section 9.2.

    10.3.3 Unless specified otherwise, all controlled fill shall be compacted to densities

    indicated in Table VI.

    10.3.4 Moisture content shall be uniform throughout the layer to be compacted and it

    shall be as close as practicable to the optimum moisture content from

    laboratory compaction tests, which will result in the maximum densification

    of the material to be compacted.

    10.3.5 Compaction of cohesionless soils by saturation and vibration shall be

    acceptable, provided, it can be demonstrated to the satisfaction of theCOMPANY Representative that required densities can be achieved by this

    method.

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    10.4 Test Section for Embankments

    10.4.1 On large earthwork projects, the COMPANY Representative shall direct for

    the construction of a test section using the material and equipment to be used

    on the project. This shall provide the basis for the most practicable processing

    and placing procedures for representative soils under job conditions. By

    varying the placement procedure within certain limits, by exercising rigid

    control over the relatively small volume of the section, and by keeping

    complete records of the tests, the most applicable procedures shall be

    determined during the initial stages of construction. Results of field density

    tests made on the test section shall provide the necessary information for

    establishing construction control procedures consistent with design

    requirements. This is to establish the moisture content of the borrow material;methods for correcting borrow materials moisture content if too wet or too

    dry; roller characteristics; number of roller passes; thickness of layers; and

    effectiveness of power tamping in places inaccessible or undesirable for roller

    operation.

    If the size of the project does not warrant a test section, then experience from

    the initial placing operations shall be used to determine the above

    characteristics.

    10.4.2 Characteristics determined above shall be used to facilitate construction

    control. Compliance with estimated number of passes of a particular rollerover a predetermined layer thickness shall not, however, be considered as

    meeting the density requirements. Acceptance or rejection of earthwork shall

    depend on field density test results.

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    11.0 SLOPE PROTECTION

    11.1 Permanent Slopes

    All permanent slopes shall be designed based on the stability considerations of the

    embankment and foundation materials.

    Based on feasibility and economic considerations, permanent slopes shall be

    protected against erosion by one of the following measures:

    a. Provide a minimum of 200 mm thick rip-rap of 150-200 mm size stones over

    a 100 mm thick layer of 40 mm size crushed stone on compacted slope. Rip-

    rap and crushed stones shall be continued over the level ground beyond thetoe, and over the top embankment beyond the top edge, for a minimum

    distance of 1.0 meter or to the edge of pavement, if any, whichever is less.

    Riprap shall be tightly hand packed with least possible void space. Riprap and

    crushed stone materials shall be hard and durable.

    b. A layer of hot asphalt concrete mix, conforming to surface course per Asphalt

    Concrete Paving Standard, TCS-Q-113.01, shall be placed on clean,

    compacted and primed embankment slope to provide a 50 mm minimum

    compacted asphalt pavement thickness.

    If the top surface of the embankment is paved, the increased runoff fromprecipitation shall be collected by provision of curbing around edges of the

    pavement and directing the flow of water down the slope through cement

    grouted rip-rap gutters. Typical sections of curbs and gutters arrangement are

    shown in the attached drawings (Figures 4, 5 and 6). Precast concrete gutter

    units may be used if approved by COMPANY Representative.

    c. Protection wire-mesh designed as slope protection blanket to intercept rock-

    fall shall be provided around the structure pads. The mesh shall be flexible

    hot-dip galvanized wire mesh.

    d. Rock-fall protection netting

    e. High resistance rock-fall netting

    f. Galvanized box gabions

    g. Lined Concrete of minimum 150 mm thick with reinforcing wire mesh.

    Compressive strength fc of concrete shall be minimum of 21 MPa.

    11.2 Temporary Slopes

    The temporary slopes, when constructed, shall be maintained in a stable and firm

    condition including proper surface drainage and control of erosion.

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    a. Excavation and Replacement:

    This scheme is suited to modification of shallow Sabkhah soils, i.e., if

    the Sabkhah layer is of shallow depth. The fill of appropriated soil to

    replace the Sabkhah layer shall be as classified in Sec. 9.1, and

    compacted to the required density as suggested in Table VI.

    b. Displacement, Excavation and Replacement:

    This procedure is used for access roads and pavements, and when

    subsurface conditions favor displacement. Filling proceeds from one

    end of the area to be developed, by building a rolling surcharge fill,

    which penetrates and displaces the Sabkhah soil to a certain depth.The Sabkhah in front of the surcharge fill is excavated to a firm base

    and the rolling surcharge is pushed forward to displace any Sabkhah

    material that may have squeezed in after excavation. This is continued

    until the entire filling procedure is completed.

    c. Surficial Chemical Stabilization:

    Sabkhah soils stabilized with cement, lime, etc., have numerous

    applications such as in backfilling, paving slopes, embankment

    protection, lining ditches, access roads, etc. Properly chemically-

    stabilized soils gain higher strength, more erosion resistance, markedlyhigh volume change stability against swelling and shrinkage. It is

    essential to assess the performance of chemically-stabilized Sabkhahs

    upon wetting, as related to the type of construction.

    12.2.2 Deep Soil Densification

    Deep soil modification techniques have to be adopted, as suited to the case in

    question, on large scale construction projects.

    The suitability of these improvement techniques is dependent on the requireddepth and degree of compaction, type of Sabkhah soil (clayey or sandy), its

    clay and organic contents, gradation, contents of fines, degree of saturation,

    location of groundwater table, risks involved, available equipment and time,

    local experience and economic feasibility of the structure.

    a. Vibration Methods

    i. Vibroflotation:

    This is a traditional deep compaction method, employed for

    granular soils. In this method, 0.3 m to 0.45 m diameter pokervibrators (vibroflots) are used to transmit vibrations to the soil

    along the whole length of the vibrator or at the tip. The

    vibrators are provided with water jets/ compressed air at top

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    and bottom to improve the penetration rate and to stabilize the

    borehole. The vibrators are also provided with fins to increase

    the efficiency and to reduce the twisting during compaction. Acutting ring is used to widen the hole when there are cemented

    layers or seams in the soil.

    While employing this method, care shall be taken to ensure

    that the flush water does not cause leaching of salt in the

    Sabkhah soil, and that the fines (smaller than 75 micron sieve)

    in the Sabkhah soil are not excessive. Vibroflotation is

    preferred for Sabkhahs containing mainly gravel and coarse

    sand because of the lateral displacement of the vibrator during

    compaction as they are more difficult to compact.

    ii. Vibro-compaction:

    This method is used for deep compaction of saturated granular

    soils. A vibratory hammer, which is attached to a pipe or a

    probe, is used and vibrated down into the soil. In contrast to

    vibroflotation, the vibrations are in the vertical direction only.

    The shaft is pulled out slowly as the soil is vibrated. The

    required spacing of the compaction points depends on the

    depth, permeability, gradation and fines content of the soil.

    Sabkhahs containing medium to fine sand are generally

    compacted by this method.

    iii. Vibro-replacement:

    This method is employed in Sabkhahs containing mainly soft,

    relatively impervious and cohesive soils. These soils are

    penetrated with low pressure, large volume bottom jets with

    the displaced material brought to surface through the water

    flow. Resistant layers are overcome by direct impact of the

    machine. On reaching the desired depth, gravel backfill is

    tipped around the machine to fall down the annulus againstcontinuing upward flow of water from the bottom jet. Gravel

    accumulates at the base of the column building upwards, with

    diameters at each level depending upon the soil resistance and

    the shearing and flushing action.

    iv. Blasting:

    This method is used for granular soils to reduce liquefaction

    potential and settlements. Explosive charges are placed in

    suitably spaced, jetted or drilled boreholes at elevations

    corresponding to 50% to 75% of the required depth of thecompaction. The efficiency of the method depends mainly on

    the pore water pressures generated by blasting and the time to

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    dissipation, and the size of the liquefied zone around the

    detonation point.

    Test blasting is recommended for large jobs in order to

    determine the optimum spacing of the boreholes, the size of the

    charges, and the intervals and sequence of blasting.

    b. Displacement Methods

    i. Stone, Gravel and Sand Columns:

    This method involves the formation of compacted columns,

    or pillars, within fine grained or stable, insensitive, cohesive

    soils and cohesionless soils using poker vibrators. Themachine penetrates a thick-walled, steel casing initially closed

    at the bottom by a gravel plug, both by vibratory impact (drop

    hammer) and by its own weight. There is no removal of soil,

    which is displaced laterally involving local shearing as in

    driven piling. Compressed air is used through the bottom jet

    during penetration.

    On reaching the requisite depth, the gravel plug is extruded and

    new material is added as the casing is withdrawn. The

    machine is lowered on top acting to displace the backfill

    laterally and downwards like a vibratory hammer. Theprocedure is repeated at each measured lift until the column is

    completed. The columns are placed in a triangular or

    rectangular grid pattern at spacing as determined by soil

    conditions and approval of the COMPANY.

    A blanket of sand or gravel, 0.6 m or more in thickness, is

    usually placed over the top of the stone columns. This blanket,

    along with the columns serves both as a drainage layer and

    large diameter drains. Also, it distributes the stresses from the

    structures above and reduces settlement.

    ii. Compaction Piles:

    This method is economical for relatively small areas compared

    with other soil improvement methods for fine-grained soils.

    The compaction is partly caused by the vibrations from driving

    the piles and partly by displacement of the soil caused by the

    piles. A relatively large spacing is normally chosen for the

    first few piles. Additional piles are then driven if the required

    penetration resistance and relative density have not been

    reached.

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    iii. Dynamic Compaction (Heavy Tamping):

    This method involves the compaction of granular soils, using

    heavy tamping, where pore water pressure variation becomes

    virtually instantaneous and used to densify loose granular fills.

    iv. Dynamic Consolidation:

    This is similar, in essence, to dynamic compaction; however, it

    deals with the improvement of fine grained soils, using several

    phases of heavy tamping, with time intervals dictated by pore

    water pressure response and dissipation. This method does not

    work properly if the low permeability Sabkhah layer exceeds 3to 4m in thickness. A 1m thick layer of free draining material

    is normally placed over the area before the tamping to improve

    the transfer of energy to the soil.

    v. Squeeze and Compaction Grouting:

    Granular soils can be improved by squeeze and compaction

    grouting.

    At squeeze grouting, relatively thin cement slurry is used,

    where the grout penetrates into the soil. Relatively thick slurryis employed at a relatively high grout pressure in compaction

    or consolidation grouting. This method is mainly applied in

    Sabkhahs containing soft compressible silts and sandy silts

    below the groundwater table. The boreholes are vertical and

    grouted from the top downwards. Penetration grouting using

    cement, silica or different chemicals is employed to reduce the

    permeability of the soil, rather than to reduce the

    compressibility or to increase the shear strength and the

    bearing capacity of the foundation soils.

    12.2.3 Loading Methods:

    Preloading:

    Preloading followed by complete or partial unloading is used to reduce the

    settlements in Sabkhahs containing granular soils. Bonding between soil

    particles is not destroyed during the loading, and compressibility is greatly

    reduced. Vertical sand wicks at uniform spacing can be used to accelerate the

    consolidation.

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    12.3 Drainage Control

    In order to protect the Sabkhah itself (against salt dissolution), as well as the

    embedded substructures against brine saturation due to capillarity, it is vital to

    implement effective drainage control measures in conjunction with soil densification

    techniques.

    Radial and horizontal sand/gravel drains are effective means of controlling drainage

    in Sabkhah. However, these drains may become clogged if the Sabkhah contains a

    large proportion of fines.

    Geotextiles are versatile, cost-effective and multi-functional (reinforcement,

    separation, drainage, etc.) materials that are used in drainage control of Sabkhahsoils intercepting the capillary fringe. The use of Geotextiles significantly improves

    the inferior properties of Sabkhah sub-grade, particularly when the natural Sabkhah

    Fabric Aggregate (SFA) system is saturated.

    Other methods generally used for Drainage control are:

    a. Well Point system, (See Section 8.0)

    b. Two-Way Subsoil Drainage system

    c. Cofferdams

    d. Electro-osmosis

    e. Electrolysis

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    13.0 QUALITY CONTROL, INSPECTION, AND REPORTS

    13.1 Quality Control and Inspection

    The quality of construction shall be determined by visual examination, by

    measurements, and by testing. The extent to which each of these procedures is

    employed shall depend on local conditions, on the importance and value of the work

    being inspected. The frequency of each type of inspection shall vary as the work

    progresses. During the entire construction stages, testing shall be conducted at

    frequent intervals.

    The inspection operation shall determine whether requirements of the approved

    plans/drawings and specifications are being satisfied. Testing shall be sufficient toprovide adequate quality control and to furnish the necessary permanent records.

    Testing shall be performed on selected samples of work or materials, which are

    representative of some unit of work or material. More specifically, inspection shall

    determine whether the material meets the gradation requirements, whether

    compaction equipment complies with specification and is maintained in working

    order, whether the thickness of lifts and the number of passes produce adequate

    compaction, and whether moisture is at optimum limit and uniformly distributed

    within the layer. Inspection shall be supported with field tests to determine the

    degree of compaction and conformance of the supplied material.

    Mechanical tamping when used around structures, along abutments, and in areas notaccessible to the rolling equipment, shall be checked by frequent density tests.

    The areas of low density, and any other faults, shall be identifed by ascertaining the

    causes and shall be rectified on instructions from COMPANY Representative by

    sprinkling, scarifying, removal, or re-rolling, as required. As a minimum, one field

    density test (ASTM D 1556 or ASTM D 2922) shall be made as follows:

    a. In areas where degree of compaction is doubtful

    b. In localized areas of concentrated controlled fill operations

    c. For every 100 square meters of controlled fill when no doubtful or

    concentrated areas occur on large earthwork projects

    d. For every 25 linear meters of controlled fill when no doubtful or concentrated

    areas occur on small earthwork projects, such as backfilling utility trench

    excavations

    e. In areas subjected to structural loads, such as foundations for buildings,

    transformers, circuit breakers, etc.

    f. During each shift involving placing of earth materials

    g. For each layer of controlled fill placed

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    13.2 Reports

    A record shall be maintained throughout the construction operations. Reports shall

    be made of every test performed in the laboratory and in the field by the approved

    independent testing agency and shall be submitted directly to the COMPANY.

    COMPANY Representative shall make daily reports concerning adequacy, progress

    and the comments on decisions.

    14.0 FINAL GRADING AND CLEANUP

    14.1 At the end of all construction work, all holes, ruts, settlements and depressions shall

    be filled and the whole area graded to final design elevations. All areas disturbed byconstruction shall be restored to their original condition to the satisfaction of the

    COMPANY Representative.

    14.2 All debris, waste, excavated spoils and surplus articles and materials shall be

    transported and/or discarded in a manner approved by the COMPANY

    Representative.

    15.0 BIBLIOGRAPHY AND APPENDICES

    15.1 Bibliography

    1. Soil Dynamics, Deep Stabilization and Special geotechnical construction by

    NAVFAC Dept. Navy, U.S.A. April 83

    2. Geological Survey (Drilling in Sabkhahs of Dhahran Area) by Ministry of

    Petroleum and Mineral Resources, Jeddah, K.S.A.

    3. Geotechnical Investigation for New Generation Projects at Ghazlan by OEO,

    K.S.A.

    4. Pile foundation (Second Edition), Robert D. Chellis

    5. Soil Survey for Engineering by ABA Brink, TC Partridge & AAB Williams

    6. Design and Construction of Foundations, by Cement and Concrete

    Association

    7. Developments in Soil Mechanics, by C.R. Scott

    8. Indian Practical Civil Engineers Handbook, by P.N. Khanna

    9. Specialists Ground Treatment by Vibrating and Dynamic methods, by D.A.

    Greenwood, K. Kirsh & G.K.N. Keller Limited

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    10. Geotechnical Properties of Soils, by Dr. Saad A Aiban, K.F.U.P. M.

    11. Soil Stabilization and Ground Improvement Overview by Dr. Saad A

    Aiban, K.F.U.P.M.

    12. Chemical Stabilization of Soils Using Cement and Lime, by Dr. Omer

    Sayeed Baghbara Al-Amoudi, K.F.U.P.M.

    13. Principles of Geotechnical Engineering, by Brajer M Das, P W S

    Engineering, Boston, U.S.A.

    14. Soil Stabilization and Grouting, by Hans F Winterkorn, Sibel Pamuken

    Ph.D., Princeston Univ, U.S. A.

    15. Symposium on Maintenance System and Application of Materials in the

    Saudi Arabian Environment, by Research Institute, K.F.U.P.M.

    16. Foundation Analysis and Design, by Joseph E. Bowles McGraw Hills Co.,

    Inc,. U.S.A.

    17. General Specifications for Building Construction in Kingdom of Saudi

    Arabia- Latest Edition.

    15.2 APPENDICES

    I. Construction Safety: Special Manual Chapter No. 6: Excavation.

    II. Construction Safety: Special Manual Chapter No. 14: Electrical Hazards.

    Note: These Safety Manuals will be revised/updated by the concerned Department.

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    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    Appendix I. CONSTRUCTION SAFETY: SPECIAL MANUAL NO. 6.483

    ISSUED BY: INDUSTRIAL SECURITY DEPARTMENT

    (LOSS PREVENTION)

    SUBJECT: CHAPTER 6.0 EXCAVATION.

    6.0 EXCAVATION.

    6.1 Introduction

    Construction w6rk involving excavation, either in sandy, rocky asphalt, or concreteareas should be adequately protected by the installation of construction fences,

    barricades, guard rails, warning tapes, road and traffic signs, and warning lights. This

    is based on the assumption that once an area is excavated the ground cannot be relied

    upon to support its own weight. For example, an excavated rocky area may appear

    solid and stable when structures on it are on the verge of collapse. Stability should

    not be taken for granted. Workers and the public must be protected from injury.

    Accidents due to excavations may involve injuries that are minor, serious, disabling

    or fatal as well as property damage. It is essential that appropriate precautions be

    taken to prevent collapse of any excavated structure or area.

    Excavation work done in urban areas and cities usually involve the presence of

    underground facilities such as utility lines (water, electricity, gas or telephone),

    tanks, process piping, and drainage systems. If they are dug into, undercut, or

    damaged in any way injury or death may result. Interruption of service,

    contamination of water, disruption of processes, or extensive delay of Government

    projects may also occur. These accidents will cause direct and indirect losses to the

    COMPANY.

    6.2 References For Standard Safety Requirements.

    6.2.1 SEC Accident Prevention Manual.

    6.2.2 Loss prevention requirements in construction contracts under Schedule A.

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    6.3 Prior To The Start Of Work

    The following items should be seriously considered prior to starting an excavation in

    order to determine the safety measures needed:

    6.3.1 Size of the area to be excavated. According to OSHA if an excavation is

    deeper than 1.5m (5 ft.) adequate bracing and shoring must be provided or

    the trench must be sloped

    6.3.2 Purpose of excavation

    6.3.3 Nature and type of ground surface to be excavated

    6.3.4 Proximity to adjacent structures

    6.3.5 Method of excavation.

    6.3.6 Adjacent roads and walkways

    6.3.7 Weather conditions

    6.3.8 Sources of vibration

    6.3.9 Position of any underground utilities such as water, gas, electric andtelephone lines

    6.4 Work Permit

    A work permit should be obtained from the Operations Supervisor of SEC before

    any excavation work in a restricted area is started. Normally, a separate work permit

    is required for each excavation. Refer to SEC General Instruction LP-002/83 or

    Chapter 13 of this manual for Work Permit procedures.

    6.5 Underground Utilities And Obstructions.

    6.5.1 Mechanical excavators should not be used in an area where underground

    utilities, pipes, cables, vessels, or tanks are known or suspected to exist until

    all such obstructions are exposed by manual digging.

    6.5.2 Mechanical excavators should not be used within 3m (10 ft.) of known

    underground utilities and obstructions.

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    6.6 Safety Precautions To Be Applied In Excavation Work

    6.6.1 Shoring should be used immediately, or the sides sloped to a safe angle, if

    there is a possibility of the sides of an excavation collapsing.

    6.6.2 Shoring material must meet accepted engineering requirements and

    standards.

    6.6.3 Excavations should be provided with appropriate road, traffic, or warning

    signs to warn the public of construction hazards

    6.6.4 A careful inspection of the excavation area and the shoring system should be

    made each day by the Contractor and the SEC Project Management Team.

    6.6.5 Workers should not be allowed to work in location where there is a

    possibility of being struck by a mechanical excavator

    6.6.6 Wooden planks or temporary walkways should be installed over an excavated

    area for use by workers crossing to the other side

    6.6.7 Trenches should not be used. for dumping materials and rubbish

    6.6.8 Warning lights and barricades should be installed on each side of an

    excavation

    6.6.9 Any excavation made in public roads, streets and sidewalks should be cleared

    in advance with Government Relations and have the approval of relevant

    authorities- See Paragraph 6.4 or Chapter 13 of this manual.

    6.6.10 Excavations should be back filled properly after installation of electrical

    equipment such as ring main unit, mini-pillar boxes, pole mounted

    transformers, etc.

    6.6.11 Excavation of hard rock that requires drilling and blasting activities shall becovered by a special permit. SEC Government Relations, Industrial Security

    Department, and Project Management must be consulted and informed before

    any blasting work.

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    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Date of Approval: Apirl 10, 2006

    Appendix II. CONSTRUCTION SAFETY: SPECIAL MANUAL NO. 6.483

    ISSUED BY: INDUSTRIAL SECURITY DEPARTMENT

    (LOSS PREVENTION)

    SUBJECT: CHAPTER 14.0- ELECTRICAL HAZARDS

    14.0 ELECTRICAL HAZAR

    14.1 Introduction

    As a source of power, electricity is in some ways less hazardous than steam or other

    sources of energy. If used properly it is a most versatile form of energy. However, if

    one fails to take suitable precautions in its use the result may be bodily harm or

    property damage as there are hazards in installing, maintaining, and using electrical

    equipment. Control of most of these hazards is neither difficult nor expensive but

    ignoring or neglecting them may lead to serious accidents. Current flow is the factor

    that causes injury in: electric shock. The severity of the shock is determine4 by the

    amount of current flow through the victim. Other factors affecting the severity of

    injuries are the parts of the body injured, duration of current flow through the victim,

    the frequency of the alternating current.

    14.2 References For Standard Safety Requirements

    14.2.1 SEC Accident Prevention Manual

    14.2.2 SEC General Instruction NO. LPOO2/83, Work Permit

    14.2.3 Guidelines on Clearances, Hold Tagging procedures, and Switching Orders

    14.2.4 OSHA Regulations and Standards, Part 1926, Safety and Health Regulations

    for Construction

    14.2.5 National Electrical Code

    14.2.6 National Electrical Safety Code

    14.2.7 Contract Schedule A, Loss Prevention Requirements

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    14.3 Current Through The Body

    Serious shock is not entirely dependent, upon the voltage of the power source. The

    ratio of the voltage to the resistance determines the current flow and the resulting

    hazard. This ratio is presented in the following formula

    Current through the body = Voltage applied to the body divided by. Resistance of

    the body

    14.4 Temporary Electrical Facilities

    The Contractor will have to make temporary electrical installations within the

    construction site and other nearby facilities on most big construction projects. Asconstruction activities increases more electrical equipment, tools, and wiring are

    installed to meet the increase in work volume. Regardless of the changes that occur,

    good safety advice requires that all temporary electrical facilities be made in

    accordance with established safety code and engineering standards. The following

    rules apply

    14.4.1 The Contractor is responsible for temporary electrical facilities within the

    construction site as specified in the contract. Connections should be made

    with the existing SEC power supply and in coordination with SEC Power

    Operations and the Area Affairs Organizations

    14.4.2 All electrical connections and installations, whether temporary or permanent,

    shall be done according to the provisions of SEC Engineering Standards,

    National Electrical Code, and .National Electrical Safety Codes

    14.4.3 All electrical supply, communication lines, and equipment shall be of suitable

    design and construction, for the services and conditions under which they are

    to be operated

    14.4.4 All electrical supply, communication lines, and equipment shall be

    constructed, protected, worked, and maintained so as to reduce hazards to lifeand prevent danger.

    14.4.5 All work on or near electrical equipment or lines shall be carried out by, or

    under the immediate supervision of, a qualified craftsman. Whenever

    possible the equipment or line shall be de-energized. A Work permit is

    needed for this type of work

    14.4.6 All temporary wiring shall be installed in safe locations to prevent their

    damage. The installation should not pose a tripping hazard in the construction

    site

    14.4.7 All electrical connections shall be in accordance with SEC Engineering

    Standards. Taped joints without a splice box are not permitted. Connections

    to socket outlets are made with the proper plugs only

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    14.5 Work on Energized Equipment or lines

    14.5.1 Any work on energized equipment or lines requires extreme caution,

    planning, and thorough knowledge of the job. Personal protective clothing,

    equipment, and live line tools should be ready. A working panel and live line

    tools should be ready. A work permit is required.

    14.5.2 Employees shall not work alone on live equipment nor on energized lines.

    Another electrician, lineman, or helper should be standing by to give

    assistance if needed. Lead men, supervisors, or a foreman should be present

    to monitor the job

    14.5.3 The power supply shall be checked to know the exact voltage. This willdetermine the type of safety protection required to accomplish the job safely.

    The following should be followed

    14.5.3.1-5 KV is the maximum voltage on any line or equipment which can

    be worked on by hand with an electrician's rubber glove with test

    rating of 20 KV

    14.5.3.2-Work on any line or equipment above 5 KV shall be done with the

    line or equipment de-energized and grounded. This type of work

    requires approved live line tools. Hold tags are placed on de-

    energized switches, disconnects, etc.

    14.5.3.3-When working on energized line or equipment, the following

    safeguards should be applied

    14.5.3.3.1 Employees shall be insulated from insulated parts of

    energized lines or equipment

    14.5.3.3.2 Employees shall be insulated or isolated from the

    ground and grounded structures other than the one

    being worked on

    14.5.3.4-In no case, when employees are working on the same pole,

    Substation structures or from a bucket truck, shall they work

    simultaneously on energized wires or equipment of different phases

    or polarities.

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    30

    BExisting

    footing

    Minimum B or 1.0 m whichever

    is greater

    Excavation Slope (Slope stability must

    be analyzed / checked)

    FIGURE # 1- SLOPE PROTECTION FOR FOUNDATION

    (N.T.S)

    Minimum Earth

    cover (See Section

    7.3.4 )

    Service Line/

    Power Cable

    FINISHED GRADE

    Compacted backfill conforming to

    local municipal requirements

    and/ or TCS-Q-113.02.

    Minimum 150 mm clean sand

    bedding on all sides

    FIGURE # 2- UTILITY TRENCHING

    (N.T.S)

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    Minimum1.0m

    WELLPOINTS

    LoweredGround

    levelE

    xcavation

    Header

    FIGURE#3-DE-WATERINGSCHEME

    (N.T.S

    )

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    TRANSMISSION CONSTRUCTION STANDARD TCS-Q-113.02, Rev. 0

    Fig- 8 Approximate correlation of soil ratings based on CBR values for use in pavements.

    California Bearing Ration (CBR)

    AASHTO SOIL CLASSIFICATION

    General soil rating as subgrade, subbase or base

    UNIFIED SOIL CLASSIFICATION

    2 3 4 5 7 8 9 10 15 20 40 50 70 80 90 1006 30 60

    Subgrade

    Subbase

    Base

    Medium Good Excellent

    Good

    Poor

    Acceptable Excellent

    Acceptable

    GC

    GM-d

    GW

    GM-uOH CH

    MH

    CL

    ML

    SM-u

    SP

    GP

    SM-d

    SW

    SC

    OL

    A-2-5

    A-5

    A-2-6A-2-7

    A-1-aA-1-b

    A-6

    A-7-5A-7-6

    A-2-4

    A-3

    A-4

    Unacceptable


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