Soil Investigation Report

Home , Geology of Singapore, Jurong, Kallang

3 URBAN REDEVELOPMENT AUTHORITY TERM CONTRACT FOR SOIL INVESTIGATION (URA/T/13/010) Soil Investigation Works At Sungei Tengah Agrotechnology Park

CONTENTS VOLUME I Page No. 1.0 INTRODUCTION 005 1.1 General 005

2.0 FIELD WORKS 006 2.1 General 006 2.2 Description of Field Investigation 006 2.2.1 Drilling 006 2.2.2 Undisturbed Sampling 006 2.2.3 Standard Penetration Testing 006

3.0 LABORATORY TESTING 007 3.1 General 007 3.2 Code of Practice 007 3.3 Physical Properties 007 3.3.1 Moisture Content 007 3.3.2 Bulk and Dry Density 008 3.3.3 Atterberg Limit 008 3.3.4 Grain Size Analysis 008 3.4 Mechanical Properties 008

3.4.1 Unconsolidated Undrained (UU) Triaxial Test 008

3.5 Summary of Laboratory Test Results for Soils 009

4.0 SOIL CLASSIFICATION 009 5.0 LIST OF GEOLOGICAL CROSS-SECTIONS 011

REFERENCES 012

LIST OF TABLES

Table 1.1 Quantity of Field Works and Laboratory Tests 013 Table 2.1 Classification / Symbol of Soil and Rock Type 014

Report No: ECGP 2531 URA ECON GEOTECH PTE LTD

3 4 URBAN REDEVELOPMENT AUTHORITY TERM CONTRACT FOR SOIL INVESTIGATION (URA/T/13/010) Soil Investigation Works At Sungei Tengah Agrotechnology Park

Table 2.2 Geological Stratigraphy of Singapore 015 Table 2.3 Identification and Description of Soils 016 Table 2.4 Weathering Classification of Soils / Rocks 018 Table 2.5 Plasticity Chart 019 Table 2.6.1 Classification of Clays/Silts from Shear Strength 020 Table 2.6.2 Classification of Clays/Silts from SPT results 020 Table 2.6.3 Classification of Sands from SPT Results 020

LIST OF FIGURES

Fig. 1 Illustration of Boring Work 021 Fig. 2 Illustration of Standard Penetration Test 022

APPENDICES

APPENDIX A · Location Plan 024

· Borehole Location Plan 025

· As-built Borehole Locations 026

· Cross-Sections 027

· Legends for different soil and rock types 028

· Borehole Logs 029-036

APPENDIX B · Laboratory Test Results of Physical & Mechanical Properties of Soil Samples 038-097

· Certificate of Accreditations 098 aõb

Report No: ECGP 2531 URA ECON GEOTECH PTE LTD

4 1.0 INTRODUCTION

1.1 General On behalf of Urban Redevelopment Authority, Econ Geotech Pte Ltd has performed the Contract URA/T/13/010 Site Investigation Works at West Coast Vale. The field investigation for this project was carried out between 26th March 2015 and 2nd April 2015. The works described in this report have been carried out as per the specifications and under the technical direction of the client. This report presents the soil investigation based on 3 boreholes. The particulars of this project are as follows:

(a) Name of Project Site Investigation Works for Contract URA / T/13/010

(b) Location West Coast Vale (c) Client URBAN REDEVELOPMENT AUTHORITY (d) Main Contractor ECON Geotech Pte. Ltd. (e) Director Steven Ih Yeo (f) Project Manager Aung Moe (g) Period of Work Field Works 26th March 2015 – 2nd April 2015

Laboratory Works and Report 4th April 2015 – 21st April 2015 (h) Scope of Work Field Works Ø Boreholes 4 Locations Ø

Laboratory Tests Water Content, Bulk & Dry Density, Atterberg Limit Tests, Triaxial (UU) Tests, Mechanical Analysis

(Refer Table 1.1 & 1.2 for Quantities of Field and Laboratory Works)

5 2.0 FIELD WORKS

2.1 General The field works were carried out in accordance with BS 5930: 1999 “Code of Practice for Site Investigation” and / or as directed by the client. The Borehole Location Plan for proposed site investigation works is shown in Appendix-A. The as-built coordinates and reduced levels of the boreholes are also presented in respective borelogs in Appendix-A.

2.2 Description of Field Investigation 2.2.1 Drilling This investigation was performed using rotary drilling rig. A cutting tool was attached to the drilling rod to drill through the soils, which produces 100mm diameter borehole. Circulated mud water was pumped through the hollow rods into the hole to stabilize the borehole and to wash out the soil debris (resulted due to drilling) to the ground surface by pressure. Partial casing (100mmф) was used to stabilize the soil on top in the borehole apart from using mud circulation. Trial pits of size 1.0 x 0.8 x 1.0 m depth was dug manually at every borehole locations. The boreholes were terminated at the depths as suggested by the client. Illustration of boring works was shown in (Fig.2.1) During the investigation, a site bore log was done and kept by the geotechnical site supervisor to note down soil descriptions, stratum changes, SPT and coring field records.

2.2.2 Undisturbed Sampling Undisturbed samples (UD samples) were collected at the depth of 2m interval in Kallang Formation and 3m interval in OA (Old Alluvium) and other formations, unless specified by the client. Before a sample was taken, the bottom of the borehole was properly cleaned. Each sample was then collected using a 75 mm diameter by 1000 mm long thin wall sampler tube driven by hydraulic push. Samples of very stiff to hard soil were collected by using Mazier sampler. Thin wall piston samplers were used for very soft to soft soil. After a sample was retrieved from borehole, it was immediately labeled and sealed with wax at both ends before sending to laboratory.

2.2.3 Standard Penetration Testing Standard Penetration Tests (SPT) is performed at 3.0m interval in all soil layers, except in the Kallang Formation. In Kallang Formation, the SPT is conducted at 2m interval. Once the borehole reached the required test depth, the borehole was cleaned by flushing with

6 water/mud before starting the test. The test was performed by using a split barrel type sampler with a 50.8 mm external and 34.9 mm internal diameter. The test was conducted in six stages, where each stage consisted of driving the sampler 75 mm into the soil by using a free fall of 63.5 kg hammer (or monkey). The hammer was dropped from a height of 760 mm on to anvil connected to the sampler by rods. The number of blows required for each 75mm penetration was noted and the final N-value is reported as the total number of blows required to achieve the last 300 mm of penetration, the initial 150 mm of penetration being to seat the sampler and by-pass any disturbance. If, however, 100 blows were reached before a penetration of 300 mm was achieved, the test was stopped and the penetration achieved recorded.

3.0 LABORATORY TESTING

3.1 General The various laboratory tests were performed on undisturbed samples based on the testing schedule approved by the alient/consultant. The tests related to mechanical properties were performed in the Econ Geotech Laboratory. The quantities of laboratory tests are summarized in Table 1.2

3.2 Code of Practice The laboratory tests were performed in accordance with the British Standard Code of Practice BS 1377 (1990) and as per terms of accreditation under the Singapore Accreditation Council – Singapore Laboratory Accreditation Scheme. The summaries and detailed test results are presented in Appendix-B. The results are also presented in respective borehole logs.

3.3 Physical Properties 3.3.1 Moisture Content To measure moisture content, a weighed specimen is taken from an undisturbed sample and placed in a tin, where it is oven dried at 105-110◦C for 18-24 hours. The soil is weighted after the drying and the weight of water is calculated simply by subtracting the two values. The moisture content is then defined as the percentage of the weight of water over weight of dry soil.

3.3.2 Bulk and Dry Density The bulk density is the measured weight of a solid cylindrical soil specimen taken from an undisturbed sample divided by its volume. The dry density was calculated from bulk density and moisture content.

3.3.3 Atterberg Limit The liquid limit of a specimen is derived using the cone penetrometer method as to BS 1377. The plastic limit is defined as the moisture content of a specimen at the point where it can be satisfactorily rolled into a 3mm diameter thread with just starting to crumble. The soils’ plasticity index is then derived by subtracting the plastic limit from the liquid limit.

3.3.4 Grain Size Analysis The grain size analysis has been carried out utilizing both sieve and hydrometer analysis. The sieve analysis was carried out by wet sieving method in which the material was first washed through a 2 mm test sieve nested in a 63 mm test sieve. The soils retained in the sieves were then dried in an oven. The dried soils were then sieved by dry sieving by passing the soils through a series of square mesh sieves, which become progressively finer down to 63 mm mesh. Each fraction thus collected was then weighed and the percentage retained on each sieve was calculated by dividing individual weights by the total sample weight. The soils passing through 63 mm mesh was analyzed by sedimentation using hydrometer method. The hydrometer method involves measuring the rate of settlement of fine particles suspended in a solution. Utilizing the principle of Stokes’ law, particle size can be directly related to its rate of settlement in a fluid such as water. From this process, the particle diameter and percentage finer is calculated.

3.4 Mechanical Properties 3.4.1 Unconsolidated Undrained (UU) Triaxial Test This test is generally performed as a set of three single stage tests (UU). However, if the sample is not enough, the test is conducted using two or single (multistage) specimen. The general testing procedure is as explained below. With the three single stage tests, three specimens were extracted from a single undisturbed sample, and was trimmed and cut to a length to diameter ratio is about two. The specimens were then weighed before putting the rubber membrane and placing into triaxial cell. Cell pressures of 0.5sv, sv, and 2sv (where sv is total overburden pressure at the sampling depth) were applied to the three specimens followed by shearing under undrained conditions at a

8 constant rate of strain (usually 2% per minute). Axial load and displacement were recorded at regular intervals until a maximum deviator stress, or 20% of strain is reached. For tests with two specimens, cell pressure of sv and 2sv were used.

3.5 Summary of Laboratory Test Results for Soils Laboratory tests were generally performed in accordance with the British Standards Code of Practice BS 1377 (1990). The tests were carried out on undisturbed samples to determine the physical, mechanical and chemical properties. Details results of physical and mechanical properties of soil for each geological classification are presented together with borehole logs in Appendix-B. Summaries of test results are also presented respectively.

4.0 SOIL CLASSIFICATION The soil classification is based on the geological classification and British classification system as given in Appendix-A.A The consistencies of clay/silt and relative densities of sand have been classified according to the (BS5930: 1999). Classification of sand, clay and silt from SPT and Shear Strength are presented in (Table 2.9.1 to 2.9.3).

4.1 Description of Soil under Present Investigating Area Based on the borehole data and in-situ tests results obtained from the boreholes, the underlying subsoil can be sub-divided into the following layers: - FILL - KALLANG FORMATION - JURONG FORMATION

4.1.1 FILL Fill is inhomogeneous material made by man. The fill layer consists of firm to very stiff, reddish brown and light grey, slightly sandy to sandy SILT with pieces of concrete and stones. Fill layers were observed in all of the four (4) boreholes (BH1, BH2, BH3 and BH4). Thickness of the Fill layers ranges from 3.00m (BH1, BH2 and BH3) to 6.00m (BH3).

4.1.2 KALLANG FORMATION 4.1.2.1 Transitional Member (Kt) Estuarine Peaty/Organic SILT/CLAY/SAND (E) The Kallang Formation – Transitional or Estuarine Member (E) was observed in one (1) boreholes (BH1). Soft, dark brown, Peaty CLAY & PEAT with trace of sand layer was major

9 soil types of the Kallang Estuarine Member (E). Thickness of the (E) layers ranges was 3.00m (BH1).

4.1.2.2 Alluvial Member (Ka) The Kallang Formation – Alluvial Member (Fluvial SAND and Fluvial SILT/CLAY) was observed in one (1) borehole (BH3). This Alluvial Member is consisted of fine and coarse fluvial sediments such as: - Fluvial SAND (F1) - Fluvial SILT/ CLAY (F2). a) Fluvial SAND (F1) The Kallang Formation – Fluvial SAND Member (F1) was not observed in assigned area. b) Fluvial CLAY / SILT (F2) It consists of stiff, light grey, slightly gravelly sandy. (F2) layer was observed only in one (1) borehole (BH3). Thickness of (F2) layers was 3.00m (BH3) with SPT N-value 2.

4.1.2.3 Marine Member (M) Marine Member (M) of the Kallang Formation was also not observed in assigned area.

4.1.2 JURONG FORMATION (J) The soil and rock samples, retrieved from all four (4) boreholes (BH1, BH2, BH3 and BH4) indicated the occurrence of the SILTSTONE, SANDSTONE and alternation of Siltstone and Sandstone of the Jurong Formation. There were evidences of Residual Soil of Jurong Formation (S VI) to Completely Weathered Sedimentary Rocks (S V) at these boreholes. Highly Weathered Rocks (S IV), Moderately Weathered Rocks (S III), Slightly Weathered Rocks (SII) and Fresh Rocks (SI) of the Jurong Formation were not encountered until the termination depth.

4.1.2.1 The Residual Soils (S VI) of the Jurong Formation were composed of very stiff to hard, light grey, reddish brown, light purplish reddish brown mottled light grey, slightly gravelly slightly fine to medium sandy to sandy SILT. SPT N-value varies from 19 (BH1) to 31 (BH2). Thickness of Residual Soil of Jurong Formation (SIV) ranges from 3.00m (BH3) to 12.00m (BH1).

10 4.1.2.2 The Completely Weathered Sedimentary Rocks (S V) were composed of hard , light yellow to yellowish grey, light grey spotted white, purple strike whitish grey, slightly gravelly slightly fine to coarse sandy to sandy SILT; very dense, light grey, light yellowish brown to yellowish brown mottled pale purple, light brownish yellow striked yellowish grey, slightly gravelly slightly silty to silty, fine to coarse SAND. SPT N-value varies from 35 (BH1) to >100 (BH1, BH2, BH3 and BH4). Measurable thickness of Completely Weathered Rock of Jurong Formation (SV) ranges from 6.26m (BH1) to 14.19m (BH4).

4.1.2.3 The Highly Weathered Sedimentary Rocks (S IV) of the Jurong Formation was not encountered in assigned area.

4.1.2.4 The Moderately Weathered Sedimentary Rocks (S III) of the Jurong Formation was not encountered in these assigned boreholes.

4.1.2.5. The Slightly Weathered Sedimentary Rocks (S II) and Fresh Sedimentary rocks (S I) of the Jurong Formation was not encountered in these assigned boreholes.

4.1.3 Summary Summary of Geological Units in the present area is shown in Table 4.0.

5.0 LIST OF GEOLOGICAL CROSS-SECTIONS Geological cross-sections showing the soil strata profile at the borehole locations are presented in Appendix-A.

SECTION BOREHOLES

1 BH1 – BH2 – BH4 – BH3

REFERENCES

1. BS 5930: 1999.“Code of Practice for Site Investigation”, British Standard Institution. 2. Braja M. Das, 1994. Principles of Geotechnical Engineering, Third Edition. PWS Publishing Company, Boston 3. Coduto, Donald P, 1994. Foundation Design: Principles and Practices. Pentice-Hall, New Jersey. 4. Karl Terzaghi, Ralph B. Peck and Gholamreza Mesri, 1996. Soil Mechanics in Engineering Practice, Third Edition. 5. Michael Carter and Stephen P Bentley, 1991. Correlations of Soil Properties. Pentech Press, London. 6. P.W.D., 1976. “The Geology of the Republic of Singapore”, Public Works Department, Singapore. 7. DSTA, 2009. “Geology of Singapore”, 2nd ed., Defense Science and Technology Agency, Singapore.

12 SOIL INVESTIGATION WORK AT WEST COAST VALE TABLE 1.1 QUANTITY OF FIELD WORKS AND LABORATORY TESTS In Situ Test & Sampling Soil Drilling Work Soil Laboratory Test DS Undistrubed Sample

Borehole Total Soil Rock SPT TW PS MZ LL/PL UU CU Trial Pit No. Drilling Drilling Coring /Thick Size Starting Finished Depth wall Bulk Density Bulk Consolidation

Date Date Particle Density Water Content Water Grain Size (Sieve)

(m) (m) (m) (Hydro)Grain Size

13 (mxmxm)

BH1 26-Mar-15 28-Mar-15 1.0x1.0x1.0 24.26 24.26 - 8 4 - - 4 4 - - 4 4 4 - -

BH2 30-Mar-15 06-Apr-15 1.0x1.0x1.0 22.24 22.24 - 7 2 - 1 3 3 - - 3 3 3 - -

BH3 26-Mar-15 28-Mar-15 1.0x1.0x1.0 24.25 24.25 - 8 2 - - 2 2 - - 2 2 2 - -

BH4 31-Mar-15 02-Apr-15 1.0x1.0x1.0 21.19 21.19 - 7 3 - 1 4 4 - - 2 4 4 - -

Total 91.94 91.94 - 30 11 - 2 13 13 - - 11 13 13 - -

Trial Pit ~ Hand auger from GL-1.0 to 2.0m SPT = Standard Penetration Test TW= Thin Wall Soil Sample, PS= Piston Soil Sample, MZ= Mazier Sample LL/PL= Atterberg Limits Test SOIL & ROCK GEOLOGICAL REFERENCE GENERAL DESCRIPTION TYPE FORMATION (PWD, 1976)

B BEACH (Littoral) Sandy, sometimes silty, with gravels, coral and KALLANG Littoral, possibly shells also part of all other members & TEKONG

E ESTUARINE Peats, peaty and organic clays, organic sands KALLANG Transitional, (Transitional) possibly part of Alluvial and Marine.

F FLUVIAL Sands, silty sands, silts and clays KALLANG Alluvial, possibly (Alluvial) part of all other members and TEKONG.

F1 Predominantly granular soils including silty Bed of Alluvial Member of sands, clayey sands and sandy silts KALLANG

F2 Cohesive soils including silty clays, sandy Bed of Alluvial Member of clays and clayey silts KALLANG

M MARINE Very soft to soft blue or grey clay KALLANG Marine Member

O OLD ALLUVIUM Very weak to weak beds of sandstone and OLD ALLUVIUM mudstone. See C-5 for weathering classification

FC FORT CANNING A colluvial deposit of boulders in a soil matrix. Not shown in PWD (1976) BOULDER BED The matrix is typically a hard silty clay, but (also known as can be granular. The material is largely derived S3, Bouldery Clay from the rocks and weathered rocks of the or Boulder Bed) Jurong Formation

S SEDIMENTARIE Sandstones, siltstones mudstones, JURONG Tengah, Rimau, S (Rocks & conglomerate and limestone. The rock Ayer Chawan and Queenstown associated soils) has been subjected to a varying degree of Facies (plus the Pandan metamorphism. Limestone, which was not identified in PWD (1976)

G GRANITE (Rock Granitic rocks, including granodiorite, BUKIT TIMAH GRANITE and associated adamellite and granite. Residual soils)

C-3 Classificatiion/ Symbol of Soil and Rock Type

14 Geological Time Series/Stage Description of stratum Time Bp- Stratum Era Period Epoch Formation Symbol Particular Origin year Zone First Au (O1) Consists mainly decomposed organic Deposit of limnetic brackish Organic Clay material. Very soft & high water content. water

First Au(S1) Poor graded medium grain loose sand with Deposited at beach and

Sand some shell fragments. shallow water depth of sea. 6000 Marine Au(M) Very soft high water content and high Seabed deposit at 5-30m depth - Clay plasticity clay. drowned valley. 10000 Upper Alluvium First Cohesive Au(C) Very soft high water content clayey silt with Deposit of limnetic-half soil sand. brackish water. Second Organic Au(O2) Very soft decomposed organic matter with Deposit of limnetic-half Clay clay. Brackish water. Second Au(S2) Well graded sand with some organic. Deposit at shallow water Sand depth.. Holocene Brown AL(B) Lower water content stiff clay. Thickness Alteration by weathering Clay varies at each location. oxidation. 11000 Third AL(S1) Medium dense fine to medium grained sand Deposit at shallow sea water - Sand depth or beach. 15000

Lower Marine AL(M) Soft and high plasticity homogeneous clay Seabed deposit at 5-30m depth Clay with shell fragments. drowned valley. Quarter Lower nary Alluvium Second Cohesive AL(C) Soft to firm high plasticity clayey silt with Deposit of limnetic-half Soil fine sand. brackish water. Third AL(O) Soft low water content organic clay. Deposit at shallow water depth. Organic Clay Fourth AL(S2) Well graded sand with some gravel and Shallow seabed deposit. Sand organic material Weathered Zone OA(W) Irregular alternating layers of well graded Weaken and alteration by Approx

Cenozoic sandy soil and clayey silt. Very Dense and weathering/ oxidation. 3.5-5.0 Old 4 Pleistocene hard by cementation. x 10 Alluvium Cemented Zone OA(C) Materials is very hard & dense by chemical/ diagenesis.

Weathered Zone Bc(W) Very hard reddish brown clay with various Produce of fault as fault clay Boulder sizes of strong sandstone boulder. Size of and fault breccia and cemented Tertiary__ Unknown__ Clay Cemented Zone Bc(C) boulder ranges from 10-45cm. during some geological period. Residual J(R) Constituted of alternating sandstone, Wholly decomposed material Approx Soil mudstone and conglomerate. Limestone by weathering. 2.0x108 developed as thin layers. Many fault zones Completely J(C) Decomposed material by are found and material near the granite area - Weathered Zone weathering. Jurassic- Initial is disturbed. Thermal metamorphism occurs 8 Highly J(H) near the granite zone. Weak and friable material by 2.1x10 Weathered Zone weathering Jurong Formation Moderately J(M) Materials weakened near joint Weathered Zone surface by weathering. Slightly J(S) Many joints developed with Late Weathered Zone some weathering at joint

Mesozoic surface. Fresh Zone J(F) Strong massive rock.

Residual G(R Coarse-grained granodiorite and biotite Wholly decomposed material Approx Soil granite. Contains porphyrite and to soil. 2.1x108 Triassic Middle Completely G(C) lamprophyre as dike. Two types of fault Decomposed weak material by Weathered Zone system are found to develop. weathering. -

Highly G(H) Weak and friable material by 8 Bukit 2.2x10 Weathered Zone weathering. Timah Granite Moderately G(M) Material is weak near the joint. Weathered Zone Slightly G(S) Joints developed with some Initial Weathered Zone weathering at joint surfaces. Fresh Zone G(F) Strong massive rock.

C-2 Geological Stratigraphy of Singapore (M.W. TAN & A.WADA, 11TH S.E ASIAN GEOTECH. CONF., 4-8 MAY, 1993)

soils soils Very coarse Very Coarse soils Coarse (over about 65% sand and gravel sizes) Fine Soils (over about 35 (over % aboutsilt and sizes) clay 35 Organic Soil Soil Organic

C-4 Identification and Description of Soil (BS 5930, 1999)

16 Table 3.2 Identification and description of soils (continued)

PRINCIPAL Visual identification Minor constituents Stratum name Example descriptions SOIL TYPE BOULDERS Only seen complete in pits or exposures Shell fragments, RECENT Loose brown very sandy sub- COBBLES Often difficult to recover whole from boreholes pockets of peal, DEPOSITS, angular fine to coarse flint gypsum crystals, flint GRAVEL with small pockets(up Easily visible to naked eye: particle shape can GRAVEL gravel, fragments of ALLUVIUM, to 30mm)of clay. (TERRACE be described: grading can be described. brick, rootlets, plastic GRAVELS) bags etc Medium dense light brown gravelly clayey fine SAND, Visible to naked eye: no cohesion when dry: Gravel is fine (GLACIAL SAND grading can be described. DEPOSITS) using terms such as; WEATHERED BRACKLESHAM CLAY, with rare Stiff very closely sheared orange mottled brown slighlty gravelly CLAY. Gravel is fine Only coarse silt visible with hand lens; exhibits with occasional LIAS CLAY, and medium of rounded little plasticity and marked dilatancy: slightly quartzite. (REWORKED SILT granular or silky to the touch; disintegrates in WEATHERED LONDON CLAY) water; lumps dry quickly; possesses cohesion but can be powdered easily between fingers with abundant/frequent/ numerous

EMBANKMENT Intermediate in behaviour between clay and CLAY/SILT FILL, silt. Slightly dilatant %defined on a site or material specific basis TOPSOIL, or subjective Firm thinly laminated grey CLAY with closely spaced thick laminae of sand (ALLUVIUM)

MADE GROUND Dry lumps can be broken but not powdered OR GLACIAL between the fingers; they also disintegrate DEPOSITS? etc. under water but more slowly than silt; smooth CLAY to the touch; exhibits plasticity but no dilatancy; sticks to the fingers and dries slowly; shrinks Plastic brown clayey appreciably on drying usually showing cracks. amorphous PEAT (RECENT DEPOSITS)

Notes a) Or described as coarse soil depending on mass behaviour d) Gravelly sandy and/or silty or clayey

b) Or described as fine soil depending on mass behaviour e) Gravelly and/ or sandy

c) %coarse or fine soil type assessed excluding cobbles and boulders f) Gravelly of sandy

Table 2.4 WEATHERING CLASSIFICATION OF SOILS / ROCKS

Weathering Classification (Bukit Timah Granite and Gombak Norite) Grade Basis for assessment Intact strength, unaffected by weathering. Not broken easily by hammer – rings G(I) when struck. No visible discoloration. Not broken easily by hammer – rings when struck. Fresh rock colors generally G(II) retained but stained near joint surfaces. Cannot be broken by hand. Easily broken by hammer. Makes a dull or sight ringing G(III) sound when struck with hammer. Stained throughout. G(IV) Core can be broken by hand. Does not slake in water. Completely discolored. Original rock texture preserved can be crumbled by hand. Slakes in water. G(V) Completely discolored. Original rock structure completely degraded to a soil with none of the original fabric G(VI) remains. Can be crumbled by hand.

Weathering Classification for Jurong Formation (Except Pandan Limestone) Grade Basis for assessment

S(I) Intact strength, unaffected by weathering

S(II) Slightly weakened, slight discoloration, particularly along joints. Considerable weakened & discolored, but larger pieces cannot be broken by hand. S(III) RQD is generally >0, but RQD should not be used as the major criterion for assessment. Core can be broken by hand or consists of gravel size pieces. Generally highly to very highly fractured, but majority of sample consists of lithorelics. RQD generally S(IV) = 0, but RQD should not be used as major guide for assessment. For siltstone, shale, sandstone, quartzite and conglomerate, the slake test can be used de differentiate between Grade IV (does not slake). Rock weathered down to soil-like material, but bedding intact. Material slakes in S(V) water S(VI) Rock degraded to a soil in which none of the original bedding remains.

Weathering Classification for Old Alluvium Indicative SPT, Class Classifier Characteristics Blow/300mm* A Unweathered Original strength >50(cannot usually be penetrated by CPTs B Partially Weathered Slightly reduced strength with 20t load capacity)

C Distinctly weathered Further weakened 30 to 50 Greatly weakened, often D Destructured 10 to 30 mottled, bedding disturbed E Residual No bedding remains <10 * The SPT result should not be used in isolation to assess weathering.

18 19

Undrained Shear Strength (kPa) Consistency < 20 Very Soft 20 – 40 Soft 40 – 75 Firm 75 – 150 Stiff 150 – 300 Very Stiff > 300 Hard

Table 2.6.1 Classification of Clays/Silts from Shear Strength (BS5930: 1999)

Approximate Relation of Consistency to SPT N-Value (blows/300mm of penetration) Consistency < 2 Very Soft 2 – 4 Soft 4 – 8 Firm 8 – 15 Stiff 15 – 30 Very Stiff > 30 Hard

Table 2.6.2 Classification of Clays/Silts from SPT results (Terzaghi and Peck)

Approximate Relation of Relative Density to SPT N-Value (blows/300mm of penetration) Relative Density

< 4 Very Loose 4 – 10 Loose 10 – 30 Medium Dense 30 – 50 Dense > 50 Very Dense

Table 2.6.3 Classification of Sands from SPT results (BS5930: 1999)

Fig. 1. Illustration of Boring Work

Fig. 2. Illustration of Standard Penetration Test

APPENDIX - A

BOREHOLE LOCATION PLAN, GEOLOGICAL INFROMATION AND BOREHOLE DATA

· LOCATION PLAN

· BOREHOLE LOCATION PLAN

· AS BUILT BOREHOLE LOCATION PLAN

· CROSS - SECTIONS

· LEGENDS FOR DIFFERENT SOIL AND ROCK TYPES

· BOREHOLE LOGS

23 LAND PARCEL

4.5m D.R.

L O C A T I O N P L A N S C A L E : 1 : 5 0 0 0

24 AYER RAJAH EXPRESSWAY (AYE)

WEST COAST VALE

B O R E H O L E L O C A T I O N P L A N S C A L E : 1 : 2 0 0 0

25 26 SECTION1 : BH1, BH2, BH4 & BH3

GEOLOGICAL CLASSIFICATION

JURONG FORMATION KALLANG FORMATION

Drawn By: Date: VERTICAL SCALE - 1:150 Checked By: Date: HORIZONTAL SCALE - NOT TO SCALE

27 28 ECON GEOTECH PTE LTD

29 ECON GEOTECH PTE LTD

30 ECON GEOTECH PTE LTD

31 ECON GEOTECH PTE LTD

32 ECON GEOTECH PTE LTD

33 ECON GEOTECH PTE LTD

34 ECON GEOTECH PTE LTD

35 ECON GEOTECH PTE LTD

APPENDIX – B

LABORATORY TEST RESULTS

· SUMMARY OF LAB TEST RESULTS OF PHYSICAL AND MECHANICAL PROPERTIES OF SOIL SAMPLES

· DETAIL TEST RESULTS OF PHYSICAL AND MECHANICAL PROPERTIES OF SOIL SAMPLES

¨ Results of Water Content & Bulk/Dry Density

¨ Results of Sieve Analysis Tests

¨ Results of Atterberg Limit Tests

¨ Results of Triaxial (UU) Tests

· CERTIFICATE OF ACCREDIATIONS

37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 SOIL INVESTIGATION REPORT

Project : Soil Investigation Work At West Coast Vale

Date : 22 April 2015

IMPORTANT:

DISCLAIMER NOTICE

The Authority shall not be held responsible in any way for the accuracy or completeness of the soil investigation report and shall not be liable for any loss or damages suffered or expenses incurred by any parties as a result of any use of or reliance on the information in the said report.

The successful tenderer/purchaser is to conduct his own soil investigation for the purpose of his planning and development of the Land Parcel.