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1
GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
GEO TECHNICAL INVESTIGATION REPORT
REPORT No.: GT /0866/2014-15
PROJECT: Soil Investigation for proposed Multi Modal Logistic Hubat Visakhapatnam, Andhra Pradesh.
CLIENT: M/s Balmer Lawrie & Co. Ltd., Kolkata-700001
W. O. No.: BL/NI/MMLH/Vizag/WO-001 dated: 22-05-2014
Completion Date: 30 June 2014
GEOTECHNICALCONSULTANTS: GEO TECHNOLOGIES
ISO 9001:2008 COMPANY
# 5-83/B, V. V. NAGAR
HABSIGUDA, STREET No. 8
HYDERABAD - 500 007
Tele/Fax: 040 – 42217757; M: 9347275255
Email: [email protected]
Website: www.geotechnologies.co.in
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
CONTENTS
S.NO. TITLE PAGE
1. INTRODUCTION 3
2. FIELD INVESTIGATIONS 4 – 6
3. LABORATORY TESTING 7
4. ANALYSIS OF DATA & RESULTS 8
5. SUB-SOIL PROFILE 9
6. RECOMMENDATIONS 10 – 18
7. TABLE–1: Summary of Drilling 19
8. TABLE–2 (a)-(c): Summary of results of Laboratory tests of soil 20 – 23
9: TABLE–3: Results of laboratory tests on rock samples 24
10. TABLE–4 (a-b): Results of Chemical Tests of soil and water 24
11. TABLE–5 (a-b): Results of Field and Lab CBR Tests 25
12. TABLE–6 (a-d): Results of DCPT Tests 26
13. APPENDIX-1: Calculations for SBC for Open foundations 27 – 28
14. APPENDIX-2: Calculations for Pile Capaciy 29 – 30
15 APPENDIX-3: Boundary wall foundations 31
16. FIG–1: Site Plan showing locations of Bore Holes, CBR and DCPT
17. FIG–2: Combined Log of Bore holes
19. Annexure-1: Field Bore Log charts
20. Annexure-2: BIS Codes
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
1. INTRODUCTION
The work of soil investigation for the proposed Multi Modal Logistic Hub project at VPT,
Visakhapatnam, was assigned to M/s GEO TECHNOLOGIES, vide Work Order No.
BL/NI/MMLH/Vizag/Wo-001 dated: 22-05-2014 from M/s Balmer Lawrie & Co. Ltd., Kolkata.
Geotechnical investigations were carried out by drilling Nine (09) bore holes, conducting
Standard Penetration Tests, collecting soil and rock samples and conducting relevant
laboratory tests. California Bearing Ratio (CBR) tests and Dynamic Cone Penetration Tests
(DCPT) were also conducted.
Fig.1. gives the Site Plan of the proposed development, showing the locations of bore holes,
California Bearing Ratio (CBR) tests and Dynamic Cone Penetration Tests (DCPT).
The aim of investigations is to determine the depth of foundations and the Safe Bearing
Capacity based on Field and Laboratory Investigations.
All the investigations are carried out in accordance with the relevant BIS (IS) Codes.
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
2. FIELD INVESTIGATIONS
OBJECTIVE:
The sub soil investigation was carried out to determine the nature of stratum and engineering
properties of soil which may affect the mode of construction of the proposed structures, and
to recommend the SBC of foundations accordingly.
BORE HOLES:
Nine (09) bore holes (BH-1 to BH-9) were drilled at the locations fixed by the client (Fig.1).
Table-1 gives the details of the bore holes drilled.
The bore holes were planned so as to yield complete information in the effective and critical
zones under the foundations.
DRILLING:
Rotary Drilling was performed as per IS: 1892. The size of the casing used was 125 to 75
mm yielding samples of NX size.
The following information was collected during the drilling operations:
Depth-wise soil profile
Depth and results of SPT
Details of soil and rock samples collected
Core recovery & RQD of rock
Color of return water
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
STANDARD PENETRATION TEST (SPT):
Standard Penetration Tests were conducted at frequent intervals in the bore holes. These
tests were performed as specified in IS: 2131-1981. In this test, a standard weight is
dropped through 75 cm height to drive the split-spoon sampler, and the number of blows
required to effect three consecutive 15 cm penetrations is recorded. The first 15 cm
penetration is considered as seating drive and neglected. Thereafter, the split-spoon sampler
is further driven for 30 cm penetration or 100 blows, whichever is reached earlier. The total
number of blows for the second and third 15 cm penetrations is designated as penetration
resistance N. If less than 30 cm is penetrated, the number of blows and the depth
penetrated are recorded, and N value is recoded as N > 100. If the number of blows exceeds
100, Refusal is said to have been reached and further testing is discontinued.
FIELD BORE LOGS:
All the details collected from the field operations are presented in Logs of Bore holes given in
Annexure-1. These logs contain depth wise strata details, sample collection data, results of
Standard Penetration Tests, core recovery data, and colour of return water etc.
SAMPLES:
All the samples collected were properly packed, labeled and transported to Geo
Technologies Soil Testing Laboratory at Hyderabad.
CBR TESTS :
The CBR tests (CBR-1 to CBR-3) were conducted at three (3) locations shown in the site
plan (Fig.1), at a depth of 30 cm. The tests were conducted in accordance with IS: 2720
(Part-31): 1969 – Field Determination of California Bearing Ratio.
The equipment comprises mechanical loading jack of 10 ton capacity, with bracket and
swivel head. A bridge support is provided for a calibrated proving ring of capacity 5000 kg,
with a dial gauge to read to an accuracy of 0.002 mm. A 50-mm dia metal penetration piston
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
is used for penetration. A dial gauge held in a universal dial gauge clamp, supported by
datum bar is used for measuring the penetration. One 5-kg, 250-mm dia annular metal
weight, with a 53-mm dia central hole and two circular slotted weights of 5 kg & two circular
slotted weights of 10 kg are used as surcharge weights. Equipment to provide reaction
(truss, truck) are located such that the beam is over the centre of the surface under test.
The load is applied at the rate of 1.25 mm / min. Load readings are recorded for penetrations
of 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 4.0, 5.0, 7.5, 10.0 & 12.5 mm.
Each test was conducted with three trials (at 3 adjacent points) in unsoaked and soaked
conditions.
Soil samples were also collected from the test locations for laboratory CBR tests.
DCPT TESTS :
Dynamic Cone Penetration tests were conducted at four locations as per IS Code: 4968
(Part-1): 1976 – Method for Subsurface Sounding for Soils: Part 1: Dynamic Method using 50
mm Cone without Bentonite slurry.
A 50 mmm dia, 60 cone screwed to the driving rod and hammer assembly was used for the
test. This assembly is kept vertical with the cone resting on the ground to be tested. The
cone is then driven into the soil by allowing a 65 kg hammer to fall freely through a height of
750 mm each time. The number of blows per every 100 mm penetration of the cone is noted.
The process is repeated for three consecutive 100 mm penetration and the sum of number of
blows is recorded as DCPT value (Ncd). When the Ncd value reaches 100, it is treated as
refusal and driving is stopped.
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
3. LABORATORY TESTING
The samples were tested at the Soil Testing Laboratory of GEO TECHNOLOGIES at
Hyderabad.
The following tests were performed on the Soil samples:
Natural Moisture Content
Atterberg’s Limits (Liquid Limit & Plastic Limit)
Bulk density & dry Density
Specific gravity
Particle size distribution (a) Sieve (b) Hydrometer
Triaxial Shear / Direct Shear
Consolidation Test
Lab CBR Test (Unsoaked & Soaked)
Chemical Analysis for pH, Sulphate & Chloride on soil / water
All the tests were conducted in accordance with IS: 2720 (Methods of Tests for Soils).
The following tests were conducted on rock samples:
Unit weight of rock (Density)
Water Absorption
Porosity
Uniaxial Crushing Strength
These tests were conducted in accordance with IS: 1124 – 1974 and IS: 9143 – 1979.
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
4. ANALYSIS OF DATA & RESULTS
BORE HOLE DATA:
From the field observation charts, sub-soil profiles, showing the variation of soil strata with
depth and SPT (N) values, are drawn for all the 9 bore holes.
Fig. 2 gives the Combined Log of the 9 bore holes.
Based on the results of lab tests, physical and engineering properties of soil and rock
samples are tabulated.
Tables – 2(a) to 2(c) give the results of lab testing of soil samples.
Table – 3 gives the results of testing of rock samples.
Tables – 4(a) & 4(b) give the results of chemical tests on soil and water samples.
ANALYSIS OF CBR DATA:
CBR test data is analyzed for calculating CBR value as per IS Code: 2720 (Part 31): 1969,
Clause 5.
From the stress-penetration curves, the stress values corresponding to 2.5 mm and 5.0 mm
penetrations are read, and the California Bearing Ratio is calculated as:
CBR = (PT / PS) x 100,
Where PT = Test stress value corresponding to the chosen penetration value, and
PS = Standard stress for the same penetration value, taken from Table-1 of the Code (PS (2.5
mm) = 70 kg/cm2; PS (5 mm) = 105 kg/cm2).
Tables – 5 (a) & 5(b) give the results of Field and Lab CBR Tests.
ANALYSIS OF DCPT DATA:
The results Dynamic Cone Penetration Tests are presented as Ncd value versus depth.
Table – 6 gives DCPT results for four locations.
DCPT (Ncd) values are, by and large, correlatable with SPT values at the corresponding
depths in the nearby borehole data.
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
5. SUB-SOIL PROFILE
Based on Nine (09) bore logs, the generalized subsoil profile at the site is as follows:
Depth, m Strata N Value
0.00 – 7.00 Clay / Silty clay / silty sand 2 – 7
7.00 – 9.00 Clayey Gravel / Silty gravel 12 – 45
9.00 – 14.00 Gravel / Soft Disintegrated Rock(SDR) 38 – 100
Below 14.00 Refusal strata / Rock > 100 & Cores
Thickness of the top soil layer varies from 3.5 m to 9.5 m in different bore holes, with an
average of about 7 m. This layer consists of clay, silty clay and silty sand. N values in this
layer are very low (2 to 7). These soils are soft and weak.
It should be noted that filled-up soil exists only in the area of BH-7. Thickness of filling in the
borehole is 4.3 m.
The top soil is followed by clayey gravel / silty gravel to a depth of 6.0 – 12.0 m, with N
values varying over a wide limit (12 to 50), in different boreholes.
This is underlain by Gravel / Soft Disintegrated Rock (SDR) to a depth of 9.0 – 14.0 m. N
values in this layer vary from 38 to 100. No cores were recovered in SDR strata due to
weathering and fissuring.
SDR strata is followed by refusal strata (N > 100), consisting of SDR / weathered rock / Hard
rock. Drilling was done through this layer up to 3 m from refusal strata in BH-3 and BH-6.
Rock with core recovery is seen in bore holes BH-2, BH-3, BH-5, BH-6 and BH-9. Core
recovery varies from 42% to 82%, and RQD varies from 0% to 50%.
Water table was seen between ground level and 5.40 m in different bore holes.
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
6. RECOMMENDATIONS
The following recommendations are made for the proposed Multi Modal Logistic Hub project
at VPT, Visakhapatnam. These recommendations are based on Standard Penetration Tests
and Laboratory Tests on samples from Nine (09) bore holes, three (3) Field and Lab CBR
tests, and four (4) Dynamic Cone Penetration Tests.
Sub-soil Profile:
The subsoil profile at the site can be broadly generalized as follows:
Depth, m Strata N Value
0.00 – 7.00 Clay / Silty clay / silty sand 2 – 7
7.00 – 9.00 Clayey Gravel / Silty gravel 12 – 45
9.00 – 14.00 Gravel / Soft Disintegrated Rock(SDR) 38 – 100
Below 14.00 Refusal strata / Rock > 100 & Cores
The top layer essentially consists of clay / silty clay / silty sand. Filled-up soil is
observed only in BH-7 to a depth of 4.3 m. Thickness of the top layer varies from
3.0 m (BH-2) to 9.4 m (BH-7). N (SPT) values in this layer are very low.
The top soil is followed by clayey gravel / silty gravel to a depth of 6.0 – 12.0 m,
with N values varying over a wide limit (12 to 50), in different boreholes.
This is underlain by Gravel / Soft Disintegrated Rock (SDR) to a depth of 9.0 –
15.0 m. N values in this layer vary from 38 to 100. No cores were recovered in
SDR strata due to weathering and fissuring.
Ground water level is generally at 0 – 2 m below the present GL.
DCPT (Ncd) values at the four test locations vary from 3 to 125 in the depth range 0
to 10 m, and are, by and large, correlatable with SPT values at the corresponding
depths in the nearby borehole data.
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
Soil & Rock Properties:
Properties of top soil (clay / silty clay / silty sand) can be summarized as follows:
Parameter / Property ValueIS Classification (IS 1498) CH / CL / SM
Dry density, kN/m3 16.0 – 17.2Specific gravity 2.64 – 2.69Liquid limit, % 33 – 65Plastic limit, % 18 – 34
Cohesion, kN/m2 35 – 59Angle of Internal Friction, Φ, deg. 0 – 10
Compressibility 0.23 – 0.35CBR (Soaked) 3.0 – 4.0
Properties of clayey gravel / silty gravel are as follows:
Parameter / Property ValueIS Classification (IS 1498) GC / GM
Unit weight, kN/m3 17.9 – 19.3Specific gravity 2.65 – 2.67
Liquid limitNP
Plastic limitCohesion, kN/m2 10 – 35
Angle of Internal Friction, Φ, deg. 29 – 35
Properties of rock are as follows:
Parameter / Property Value
IS Classification (IS: 12070) Very Poor to Poor Rock –Classification No. V / IV
Dry Density, g/cm3 2.71 – 2.73Porosity, % 2.38 – 3.21
Water Absorption 1.79 – 2.93Un-Confined Compressive Strength, kg/cm2 550 – 910
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
FOUNDATIONS:
Open foundations:
Open (Footings / raft) foundations are recommended.
Safe Bearing Capacity (SBC) is recommended as follows:
B HNo
GroundLevel, m
+
SoilProfile
SBC at Depth, m (t/m2)
2.0 3.0 3.5 4.0 4.5 5.0 5.5 6.0
1 5.3 1 0 – 4 m Silty clay4 – 6 m Clayey gravel 8 10 12 12 12 15 15 15
2 3.910 – 1.2 m Silty clay
1.2 – 2 m Clay2 – 3.3 m Silty clay
3.3 – 6 m Clayey Gravel
8 10 12 15 15 15 20 20
3 4.450-1.1 m Silty sand1.2 – 3.4 m Clay
3.4 – 7.5 m Clayeygravel
8 10 10 15 15 15 20 20
4 4.250– 1.5 m Silty clay
1.5– 2 m Clay2 – 4 m Silty clay
4 – 6 m Silty Gravel
8 10 10 15 15 15 20 20
5 4.410-1 m Silty clay1 – 5.2 m Clay
5.2– 6 m Clayey gravel8 10 10 10 10 10 20 20
6 3.850-1 m Silty sand1 – 5.6 m Clay
5.6 – 8.0 m Clayeygravel
8 10 10 10 10 10 15 20
7 6.550-4.3 m Filling
4.3 – 5.8 m Silty sand5.8 – 9.4 m Clay
Fill Fill Fill Fill 10 10 10 10
8 3.85 0-1.6 m Silty sand1.6 – 6.5 m Clay 8 10 10 10 10 10 10 10
9 5.560-1.2 m Silty sand1.2 – 3.7 m Clay
3.7 – 6.0 m Clayeygravel
8 10 10 15 15 15 20 20
Notes:1. Ground level refers to MSL.2. Ground water level is generally at 0 – 2 m below the present GL.3. All foundations resting in clay / silty clay should be placed in sand bed.4. Typical calculations for SBC are given in Appendix-1.
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
Pile foundations:
Alternatively, Pile foundations may be considered.
Pile Capacities for different lengths and diameters are given separately for each
bore hole in the following table.
B HNo
GroundLevel, m
+Soil
Profile
Pile capacity Safe lateralpile
capacity,tonnesLength,
mDia,mm
VerticalCapacity,
tonnes1 5.31 0 – 4 m Silty clay
4 – 6 m Clayey gravel6 - 11.5 m Gravel N=38 - 5611.5 – 12.0 m SDR N>50
1010
450650
5075
711
2 3.91 0 – 1.2 m Silty clay1.2 – 2 m Clay2 – 3.3 m Silty clay3.3 – 6 m Clayey Gravel6 -12 m Gravel N= 51-8112-14 m SDR N=88 -10014 -15 m Rock
1010
450650
5075
711
3 4.45 0-1.1 m Silty sand1.1 – 3.4 m Clay3.4 – 7.5 m Clayey gravel7.5 – 11.4 m Gravel N=57-7011.4 -14.6 m SDR >5014.6 -17.6 m Rock
1010
450650
5075
711
4 4.25 0– 1.5 m Silty clay1.5– 2 m Clay2 – 4 m Silty clay4 – 6 m Silty Gravel6 -10 m Gravel N =49-6510-15 m SDR N 73-100
1010
450650
5075
711
5 4.41 0-1 m Silty clay1 – 5.2 m Clay5.2– 6 m Clayey gravel6- 9 m SDR N = 91-949- 10 m Rock
1010
See Note6
450650
5075
711
6 3.85 0-1 m Silty sand1 – 5.6 m Clay5.6 – 8.0 m Clayey gravel8-9.8 m Gravel N =569.8–14.8 m SDR N=50 – 9614.8 -17.8 m Rock
1010
450650
5075
711
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
B HNo
GroundLevel, m
+Soil
Profile
Pile capacity Safe lateralpile
capacity,tonnesLength,
mDia,mm
VerticalCapacity,
tonnes7 6.55 0-4.3 m Filling
4.3 – 5.8 m Silty sand5.8 – 9.4 m Clay9.4 -13.2 m Clayey gravel
(N= 50-85)13.2 -15 m SDR N>50
1010
450650
5075
711
8 3.85 0-1.6 m Silty sand1.6 – 6.5 m Clay6.5 - 8 m Clayey gravel8 – 10.6 m Gravel N = 31-6010.6 – 14 m SDR N=50-94
1010
450650
5075
711
9 5.56 0-1.2 m Silty sand1.2 – 3.7 m Clay3.7 – 6.0 m Clayey gravel6.0 – 6.7 m Gravel6.7 – 9.0 m SDR N=50-859-10 m Rock
1010
See Note6
450650
5075
711
SDR … Soft Disintegrated RockNotes on Pile foundations:
1. Ground level refers to MSL.
2. Groundwater level is generally at 0 – 2 m below the present GL.
3. Typical calculations for Pile capacities are given in Appendix – 2.
4. Lateral Pile capacity is taken as 15% of Vertical capacity.
5. All Piles considered to be of length 10 m, resting in gravel for 3 m depth.
6. (a) In BH-5 and BH-9, SDR is seen at a depth of 5 to 7 m.
(b) If SDR is reached earlier than 10 m, Piles may be rested in SDR strata, with an embedment of
1.5 m.
(c) Suggested minimum length of socket is as follows:
where D is the diameter of Pile.
7. All requirements of IS Code: 2911 shall be adhered to.
8. For other Pile Capacities, Pile dia / length may be modified.
Rock Type Embedment LengthSound Rock 1 – 2 D
Moderately weathered rock 2 – 3 DSoft Rock 3 – 4 D
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
Boundary wall foundations
Specific Recommendations for Boundary Wall Foundation:
The soils from 0 – 7 m are weak and soft soils (Clay /silty clay/silty sand). N values are less
than 10.
Considering the soft soils, the following alternatives are suggested:
Open foundations at a depth of 3 m with SBC of 10 t / sq m, and sand bed. SBC
calculations are given in Appendix – 1
Alternatively, 10 m long Piles may be used. Pile dia may be 300 mm with a vertical
pile capacity of 20 tonnes. Pile capacity calculations are given in Appendix-3.
PAVEMENT:
It should be noted that the top soil essentially consists of clay / silty clay / silty sand.
Thickness of this layer varies from 3.0 m to 9.5 m below existing ground level in
different boreholes.
Filled up soil of thickness 4.3 m exists in the area of Bore Hole-7.
Soaked CBR values of the top soil (clay/silty clay/silty sand) are quite low (3% to 4%).
Design:
As per Tender Document, Axle load transferred for each side of front axle of container
handling ‘Reach Stacker’ equipment is taken as 50 MT.
Sri Mohan Kumar, Manager, Railway Division, AARVEE Consultants, has given
Cumulative Standard Axles as 1.971 million times with full load over the surface.
From IRC: 37 – 2001 (Guidelines for Design of Flexible Pavments), Fig. 1 ( Pavement
design Thickness Chart ),
For CBR = 3 %, and Cumulative Standard Axles = 2 million,
Total Pavement Thickness T = 580 mm, say 600 mm
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GEO TECHNOLOGIES
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Pavement design of Combination Block for 2 million Cumulative Standard Axles is as
follows (IRC: 37 - 2001):
Total Pavement Thickness T = Y + Z = 600 mm
Where Y = Thickness of Granular Base = 225 mm
Z = Thickness of Granular Sub Base = 375 mm
X = Thickness of Surfacing = 20 mm
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
Base Material:
This requires the load spreading properties to reduce the stresses on the subgrade.
This has an important bearing on the performance of block pavement. Since the
available strata are unsuitable, base course should consist of unbound crushed rock,
water bound macadam, wet mix macadam, cement-bound crushed rock / granular
materials, and lean cement concrete.
In broad terms, whenever the subgrade is weak (with CBR < 5 %, as in the present
case), use of bound granular materials like cement treated crushed rock, requiring a
relatively thinner base, is recommended.
Sub - base Material:
The quality of sub-base materials includes natural gravels, cement treated gravels,
sand stabilized sub grade materials. The quality of sub grade materials should be in
conformance with IRC: 37 -2001 (Guidelines for the Design of Flexible Pavements).
Drainage:
Drainage of the pavement structural section improves its performance. Adequately
designed sub – surface drainage system consisting of an open graded drainage layer
with collector and outlet pipes should be provided (IRC: 37- 2001).
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
CHEMICAL PROPERTIES OF SOIL & WATER:
Results of Chemical analysis of soil are as follows:
Parameter Range Average
pH 7.76 – 8.02 7.9
Chlorides as Cl, ppm 420 – 445 433
Sulphates as SO4, ppm 282 – 201 242
Results of Chemical analysis of water are as follows:
Parameter Range Average
pH 6.23 – 7.15 6.7
Chlorides as Cl, mg/l 23100– 24400 23750
Sulphates as SO4, mg/l 4093 – 5068 4580
The values of Chlorides and Sulphates in water are in excess of permissible limits as
per IS: 456, and may have deleterious influence on concrete and steel. Effective
precautionary measures are required. Use of Sulphate-Resistant Cement and
Corrosion-Resistant Steel is recommended for sub-structure.
(Dr. D. BABU RAO)M.E., Ph.D. (USA), MIGS
Former Professor & Head of Civil EngineeringPrincipal Geotechnical Consultant
(Dr. N. VENKAT RAO)M.Sc. Tech., Ph.D. FAEG, MIGS
Former Professor & Head of GeophysicsGeological Consultant & Proprietor
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Project: Soil Investigation for proposed Multi Modal Logistic Hubat Visakhapatnam, Andhra Pradesh.
TABLE – 1: SUMMARY OF DRILLING
S.No. DEPTH DRILLED,(m) GL, (m)
DEPTH OFWATER
LEVEL, (m)RL of Water
BH-1 12.0 5.31 2.2 3.11
BH-2 15.0 3.91 1.8 2.11
BH-3 17.6 4.45 0.2 4.25
BH-4 15.0 4.25 1.2 3.05
BH-5 10.0 4.41 1.4 3.01
BH-6 17.8 3.85 0.2 3.65
BH-7 15.0 6.55 5.4 1.15
BH-8 14.0 3.85 0.0 3.85
BH-9 10.0 5.56 0.0 5.56
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GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
Project: Soil Investigation for proposed Multi Modal Logistic Hubat Visakhapatnam, Andhra Pradesh.
TABLE - 2: SUMMARY OF RESULTS OF LABORATORY TESTS
TABLE – 2(a): Specific gravity, NMC, Bulk and Dry Density, Atterberg Limits (LL, PL, PI) &Consolidation test (Compressibility, Cc)
SNo BH No. D, m Soil Sp.Gr. NMC
BulkdensitykN/m3
Drydensity
Atterberg LimitsCc
LL PL PI
1
BH-1
3.0 Silty clay 2.64 16.5 19.4 17.2 43 29 34 0.24
2 4.0 Clayeygravel 2.67 9.3 19.6 17.9 NP
3 6.0 gravel 2.66 6.3 20.1 18.5 NP
4 8.0 gravel 2.65 5.8 20.3 18.8 NP
5 10.0 gravel 2.65 7.5 20.7 18.9 NP
6
BH-2
2.0 Clay 2.67 18.4 18.9 16.0 61 26 35 0.33
7 4.0 Clayeygravel 2.68 7.1 19.3 18.0 NP
8 6.0 gravel 2.65 6.5 19.9 18.7 NP
9 8.0 gravel 2.66 6.1 20.1 18.9 NP
10 10.0 gravel 2.65 5.8 20.2 19.1 NP
11
BH-3
2.0 Clay 2.68 17.3 19.0 17.1 64 25 39 0.32
12 4.0 Clayeygravel 2.65 9.1 19.3 17.7 NP
13 6.0 Clayeygravel 2.67 8.3 19.4 17.9 NP
14 8.0 gravel 2.64 7.7 20.5 19.0 NP
15 10.0 gravel 2.65 6.4 20.4 19.2 NP
16
BH-4
2.0 Silty Clay 2.68 12.4 19.2 17.1 46 18 28 0.27
17 4.0 Silty gravel 2.66 10.5 20.1 18.2 NP
18 6.0 gravel 2.65 6.7 20.1 18.8 NP
19 8.0 gravel 2.66 6.1 20.1 18.9 NP
20
BH-5
2.0 Clay 2.68 17.9 19 16.1 60 24 36 0.35
21 3.0 Clay 2.67 17.5 19.1 16.3 59 26 33 0.35
22 4.0 Clay 2.67 17.1 19.5 16.7 62 34 28 0.31
23 5.2 Silty gravel 2.65 5.6 19.6 18.6 NP
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Table-2(a) Contd…
SNo BH No. D,m Soil Sp.
Gr. NMCBulk
densitykN/m3
Drydensity
Atterberg LimitsCc
LL PL PI
24
BH-6
2.0 Clay 2.68 19.1 18.9 15.9 49 25 24 0.23
25 4.0 Clay 2.68 18 19.1 16.2 54 29 35 0.31
26 6.0 Clayey gravel 2.68 7.3 19.3 18.0 NP
27 8.0 gravel 2.64 5.2 19.6 18.6 NP
28 9.0 gravel 2.65 5.2 19.8 18.8 NP
29
BH-7
5.0 Silty Sand 2.66 12.3 19.1 17.0 33 21 12 0.27
30 6.0 clay 2.69 18.3 18.7 15.8 65 34 31 0.33
31 8.0 clay 2.67 17.7 19.0 16.1 62 32 30 0.34
32 10.0 Silty gravel 2.65 7.2 19.4 18.1 NP
33 12.0 gravel 2.66 5.8 20.4 19.3 NP
34
BH-8
2.0 clay 2.68 16.1 19.2 16.5 64 29 35 0.30
35 4.0 clay 2.67 17.6 19.1 16.2 50 24 25 0.34
36 6.0 clay 2.69 16.1 19.7 17.0 52 28 24 0.30
37 8.0 gravel 2.65 3.3 18.6 18.0 NP
38
BH-9
2.0 clay 2.68 16.3 19.2 16.5 55 22 33 0.32
39 4.0 Clayey gravel 2.66 7.8 19.1 17.7 NP
40 6.0 gravel 2.65 2.6 19.1 18.6 NP
NOTATION:D … Depth, m, Sp. Gr. … Specific gravity, NMC … Natural Moisture Content %,LL … Liquid Limit %, PL .. Plastic Limit %, PI .. Plasticity Index, NP .. Non plastic,Cc … Compressibility.
22
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Balmer Lawrie & Co. Ltd.
TABLE – 2(b): Particle size Distribution (Sieve & Hydrometer)
S. No BH No. D, m SoilGrain Size, %
Gr Sa Si Cl
1BH-1
3.0 Silty clay 0 0 21 79
2 4.0 Clayeygravel 27 33 15 25
3BH-2
3.0 Silty clay 3 12 19 66
4 4.0 Clayeygravel 29 40 11 21
5BH-3
3.0 Clay 0 0 5 95
6 8.0 gravel 60 18 19 3
7BH-4
4.0 Silty gravel 37 41 18 4
8 6.0 gravel 47 33 12 8
9BH-5
4.0 Clay 0 0 29 71
10 5.2 Silty gravel 29 46 15 10
11BH-6
6.0 Clayeygravel 36 27 27 10
12 8.0 gravel 43 28 21 8
13BH-7
6.0 clay 0 0 33 67
14 12.0 gravel 56 11 27 6
15
BH-8
6.0 clay 0 0 24 76
16 8.0 gravel 45 25 21 9
17 10.0 gravel 41 32 23 4
18
BH-9
2.0 clay 0 3 27 70
19 4.0 Clayeygravel 36 23 18 23
20 6.0 gravel 58 16 22 4
Notation: D … Depth, mGr … Gravel >4.75 mm Sa … Sand 4.75 – 0.075 mm Si … Silt 0.075 – 0002 mmCl… Clay < 0.002 mm,
23
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TABLE – 2(c): Direct / Triaxial Shear Tests
S. No BH No. D, m SoilDirect Shear Triaxial Shear
C, kN/m2 Φ, deg C, kN/m2 Φ, deg
1
BH-1
2.0 Clay 46 3
2 4.0 Clayey gravel 14 29
3 6.0 gravel 10 33
4 8.0 gravel 8 34
5
BH-2
2.0 Clay 51 0
6 4.0 Clayey gravel 10 31
7 6.0 gravel 15 34
8 8.0 gravel 11 35
9
BH-3
2.0 Clay 54 3
10 4.0 Clayey gravel 7 30
11 6.0 Clayey gravel 11 32
12 8.0 gravel 13 35
13
BH-4
2.0 Silty Clay 35 10
14 4.0 Silty gravel 12 33
15 6.0 gravel 10 34
16 8.0 gravel 13 35
17
BH-5
2.0 Clay 49 5
18 4.0 Clay 52 0
19 5.2 Silty gravel 14 33
20
BH-6
2.0 Clay 52 0
21 4.0 Clay 57 0
22 6.0 Clayey gravel 13 32
23 8.0 gravel 10 34
24
BH-7
5.0 Silty Sand 13 31
25 6.0 clay 50 3
26 8.0 clay 53 0
27 10.0 Silty gravel 14 34
28 12.0 gravel 12 35
29BH-8
6.0 clay 59 0
30 8.0 gravel 8 34
31BH-9
2.0 clay 49 5
32 6.0 gravel 11 34
C … Cohesion, kN/m2, Φ … Angle of Internal Friction, deg.
24
GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
Project: Soil Investigation for proposed Multi Modal Logistic Hubat Visakhapatnam, Andhra Pradesh.
TABLE - 3: RESULTS OF LABORATORY TESTS ON ROCK SAMPLES
BOREHOLE
No.DEPTH OF
SAMPLE (m)Unit
Weight,kN/m3
Porosity(%)
Waterabsorption UCC, kg/cm2
BH-3 14.6 – 15.6 27.1 3.21 2.93 550
BH-6 16.8 – 17.8 27.3 2.38 1.79 910UCC … Unconfined Compressive Strength
TABLE - 4 (a): RESULTS OF CHEMICAL ANALYSIS OF SOIL
Sno. Parameter Units BH-2,SPT-2.0m
BH-5,SPT-4.0m
BH-8,SPT-6.0m
1 pH (1:5 Solution) --- 7.76 8.02 8.00
2 Chlorides as Cl Ppm 445 420 430
3 Sulphates as SO4 Ppm 201 197 182
TABLE - 4 (b): RESULTS OF CHEMICAL ANALYSIS OF WATER
Sno Parameter Units Bore Water-1 Bore Water-2 Permissible valuesas per IS: 456
1 pH -- 6.23 7.15 Not less than 6
2 Chloride as CaCo3 mg/l 24400 231002000 for Concrete500 for Reinforced
Concrete
3 Sulphate as CaCo3 mg/l 5068 4093 400
25
GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
Project: Soil Investigation for proposed Multi Modal Logistic Hubat Visakhapatnam, Andhra Pradesh.
TABLE - 5 (a): RESULTS OF FIELD CBR TESTS
S.No.
TestNo. Location
SampleDepth,
mSoil Unsoaked
CBR, %Soaked CBR,
%
1 FCBR-1 Near BH-8 0.30 Silty sand 7.3 4.2
2 FCBR-2 Near BH-4&5 0.30 Silty clay 6.6 3.4
3 FCBR-3 Near BH-2 0.30 Silty clay 6.2 3.1
TABLE - 5 (b): RESULTS OF LAB CBR TESTS
S.No.
SampleNo. Location Soil Unsoaked
CBR, %Soaked CBR,
%
1 CBR-1 FCBR-1 Silty sand 5.4 3.7
2 CBR-2 FCBR-2 Silty clay 4.9 3.5
3 CBR-3 FCBR-3 Silty clay 5.5 3.4
Note: Lab CBR values are generally less than Field CBR values since in field CBR test, a larger volumeof soil, and hence more representative sample, is tested, and since the density of compacted CBRmould would generally be less than in-situ density as the in-situ soil is in confined condition unlikethe laboratory mould.
26
GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
Project: Soil Investigation for proposed Multi Modal Logistic Hubat Visakhapatnam, Andhra Pradesh.
TABLE - 6: RESULTS OF DCPT TESTS
Table-6(a): DCPT-1 (Near BH-1)
Sno Depth DCPT (Ncd)
1 2.0 82 4.0 183 6.0 674 8.0 985 10.0 121
Table-6(b): DCPT-2 (Near BH-3)
Sno Depth DCPT (Ncd)
1 2.0 82 4.0 513 6.0 794 8.0 1005 10.0 123
Table-6(c): DCPT-3 (Near BH-5)
Sno Depth DCPT (Ncd)
1 2.0 52 4.0 63 6.0 1094 8.0 125
Table-6(d): DCPT-2 (Near BH-8)
Sno Depth DCPT (Ncd)
1 2.0 32 4.0 53 6.0 94 8.0 555 10.0 1056 12.0 118
27
GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
Project: Soil Investigation for proposed Multi Modal Logistic Hubat Visakhapatnam, Andhra Pradesh.
APPENDIX-1: CALCULATION OF SAFE BEARING CAPACITY FOR OPEN FOUNDATIONS
a) Foundations resting in clay / silty clay at 2 m depth:i)Shear Criterion :Assumed depth of foundation D= 2 mAssumed width of foundation B= 2 mUnit wt of soil = 16.0 kN/cum Submerged unit wt r’= 6.2 kN/cu mCohesion c = 35 kN / sq m Angle of internal friction = 0 degNc = 5.14 Nq =1.0 Nr = 0,0Using IS Code: 6403-1981 formula :Net ult BC = 1.3 cNc + r’ D ( Nq - 1) + 0.4 r’B Nr
= 234 kN/sq mWith a FS of 3.0, SBC = 78 kN/ sq mRecommended SBC is 8 t / sq m, with sand bed.ii)Settlement Criterion :As per IS: 8009( Part 1)-1978Settlement = [ p B ( 1- µ2 ) I ] / E
Where, p = Pressure, kN/ sq m = 78 kN/ sq mµ = Poisson’s ratio = 0.5 E = Young’s Modulus = 5000 kN/sq mI = Influence Factor =0.95
Substituting, Settlement = 22.5 mm < 40 mm (OK)
a) Foundations resting in clay / silty clay at 3 m depth:i)Shear Criterion :Assumed depth of foundation D= 3 mAssumed width of foundation B= 2 mUnit wt of soil = 16.0 kN/cum Submerged unit wt r’= 6.2 kN/cu mCohesion c = 45 kN / sq m Angle of internal friction = 0 degNc = 5.14 Nq =1.0 Nr = 0,0Using IS Code: 6403-1981 formula :Net ult BC = 1.3 cNc + r’ D ( Nq - 1) + 0.4 r’B Nr
= 300 kN/sq mWith a FS of 3.0, SBC = 100 kN/ sq mRecommended SBC is 10 t / sq m, with sand bed.ii)Settlement Criterion :As per IS: 8009( Part 1)-1978Settlement =[ p B ( 1- µ2 ) I ] / E
Where, p = Pressure, kN/ sq m = 100 kN/ sq mµ = Poisson’s ratio = 0.5 E = Young’s Modulus = 5000 kN/sq mI = Influence Factor =0.95
Substituting, Settlement = 28.5 mm < 40 mm (OK)
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b) Foundations resting in clay gravel / silty gravel at 3 m depth:
i)Shear Criterion :Assumed depth of foundation D= 3 mAssumed width of foundation B= 2 mUnit wt of soil = 17.0 kN/cum Submerged unit wt r’= 7.2 kN/cu mCohesion c = 32 kN / sq m Angle of internal friction = 30 degNc’= 16.17 Nq’ =7.36 Nr’ =6.64Using IS Code: 6403-1981 formula :Net ult BC = 1.3 c’Nc + r’ D ( Nq’ - 1) + 0.4 r’B Nr ‘
= 619 kN/sq mWith a FS of 3.0, SBC = 206 kN/ sq mRecommended SBC is 20 t / sq m.
ii)Settlement Criterion :As per IS: 8009 (Part 1)-1978 (Fig. 9)For B= 2, N = 35Settlement in m per unit pressure (kg/sq cm) =0.006Settlement for Pressure of 200 kN/sq m (2 kg/sq cm) = 0,006 x 2 x 1000
=12 mm < 40 mm (OK)
29
GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
Project: Soil Investigation for proposed Multi Modal Logistic Hubat Visakhapatnam, Andhra Pradesh.
APPENDIX-2: Typical Calculations for Pile Capacity
a) Cast in situ Bored RCC Piles : Pile Diamter D = 450 mm
Vertical Load:
Perimeter = P = 1.413 m C/S area A =.0.16 sq m
Length of pile L = 10 m, including 3 m embedment in gravel
Unit weight r = 16 kN/cu m Effective unit wt r’= 6.2 kN/ cum
End bearing :
Average angle of internal friction at pile tip φ = 40 deg ( for N = 50) IS :6403
Corresponding Nq value is 140 (IS: 2911 – 1982 )
Ultimate pile capacity in bearing :
Q b = A r’ L Nq = 0.16 x 6.2 x 10 x 140 = 1389 kN
Skin friction :
Neglect skin friction in clay/silty clay
For gravel :
Angle of wall friction = δ = 30 degrees (assumed)
Earth pressure coefficient K = 0.75 ( assumed )
fs= 0.5 x r’ x L x K x tan δ = 0.5 x 6.2 x 3 x 0.75 x 0.58 = 4 kN/ sq m
Qf = fs x P L = 4 x 1.413 x 3 = 17 kN
Pile capacity = Qb + Qf = 1389 + 17 = 1406 kN
With a FS of 2.5, Safe Pile capacity = 562 kN
Recommended vertical Pile capacity = 50 tonnes
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b) Cast in situ Bored RCC Piles : Pile Diamter D = 600 mmVertical Load :Perimeter = P = 1.884 m C/S area A =0.28 sq m
Length of pile L = 10 m, including 3 m embedment in gravel
Unit weight r = 16 kN/cu m Effective unit wt r’= 6.2 kN/ cum
End bearing :
Average angle of internal friction at pile tip φ = 40 deg ( for N = 50) IS :6403
Corresponding Nq value is 140 (IS: 2911 – 1982 )
Ultimate pile capacity in bearing :
Q b = A r’ L Nq = 0.28 x 6.2 x 10 x 140 = 2430 kN
Skin friction :
Neglect skin friction in clay/silty clay
For gravel :
Angle of wall friction = δ = 30 degrees (assumed)
Earth pressure coefficient K = 0.75 ( assumed )
fs= 0.5 x r’ x L x K x tan δ = 0.5 x 6.2 x 3 x 0.75 x 0.58 = 4 kN/ sq m
Qf = fs x P L = 4 x 1.884 x 3 = 22.6 kN
Pile capacity = Qb + Qf = 2430 + 22.6 = 2453 kN
With a FS of 2.5, Safe Pile capacity = 981 kN
Recommended vertical Pile capacity = 75 tonnes
31
GEO TECHNOLOGIES
Balmer Lawrie & Co. Ltd.
Project: Soil Investigation for proposed Multi Modal Logistic Hubat Visakhapatnam, Andhra Pradesh.
APPENDIX-3 Typical Calculations for Boundary wall foundations
Cast in situ Bored RCC Piles : Pile Diamter D = 300 mmVertical Load :
Perimeter = P = 0.94 m C/S area A =.0.07 sq m
Length of pile L = 10 m, including 3 m embedment in gravel
Unit weight r = 16 kN/cu m Effective unit wt r’= 6.2 kN/ cum
End bearing :
Average angle of internal friction at pile tip φ = 40 deg ( for N = 50) IS :6403
Corresponding Nq value is 140 (IS: 2911 – 1982 )
Ultimate pile capacity in bearing :
Q b = A r’ L Nq = 0.07 x 6.2 x 10 x 140 = 607 kN
Skin friction :
Neglect skin friction in clay/silty clay
For gravel :
Angle of wall friction = δ = 30 degrees (assumed)
Earth pressure coefficient K = 0.75 ( assumed )
fs= 0.5 x r’ x L x K x tan δ = 0.5 x 6.2 x 3 x 0.75 x 0.58 = 4 kN/ sq m
Qf = fs x P L = 4 x 0.94 x 3 = 11 kN
Pile capacity = Qb + Qf = 607 + 11 = 618 kN
With a FS of 2.5, Safe Pile capacity = 247 kN
Recommended vertical Pile capacity = 20 tonnesPile dia may be modified for other capacities.
32
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Annexure-1
FIELD BORE CHARTS