CERTIFICATE FOR: CADD CONSULTING ENGINEERS PVT. LTD

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2 CERTIFICATE This is to certify that the samples are collected from the proposed OPGC PROPOSED FOR SOIL INVESTIGATION WORK FOR CONSTRUCTION OF CHP AREA AT MINE S END The laboratory tests have been performed under the supervision of qualified personal, as per the Indian standards and that this report is prepared on the basis of these tests results and expert experience. FOR: CADD CONSULTING ENGINEERS PVT. LTD

3 INTRODUCTION It is intended to investigate the sub soil strata at the OPGC PROPOSED FOR SOIL INVESTIGATION WORK FOR CONSTRUCTION OF CHP AREA AT MINE S END OBJECT The object of the Geo technical investigation is to:- Optimize the foundation system, assuring the safe bearing capacity of the soil. Determination of type, size and depth of foundation. Analyzing the soil properties. Suggesting an economically viable of foundation system to be adopted for the proposed structures. SCOPE OF WORK It consists of the following:- Visual reconnaissance of the site. Field and laboratory investigation. Engineering judgment based on the current practice. LIMITATIONS OF INVESTIGATION The scope of Geo- technical Sub soil investigation is confined within the framework of agreement and Technical specification with the client. However all the field and laboratory experiments will be carried out as per the relevant Indian standard code of practice?

4 THE DETAILED GEO-TECHNICAL INVESTIGATION WORK TO BE CARRIED OUT CONSISTS OF TWO PARTS. 1. FIELD INVESTIGATION Location of bore holes. Boring /drilling up to specified depth below G.L. Conducting standard penetration test. Collection UDS samples. Collecting DS samples. Determining the depth of water table. Study of site condition and surroundings. Taking observation of surrounding structure. Transportation of all soil samples to laboratory. 2. LABORATORY INVESTIGATION :- Grain size analysis. Determination of moisture content. Unconfined compressive strength. Determination of Bulk density. Determination of dry density. Determination of Void ratio. Determination of liquid limit. Determination of plastic limit & plastic index. Determination of specific gravity. Determination of shear parameters & settlement calculation. Determination of DFS test. LOCATION The proposed site of construction OF OPGC PROPOSED FOR SOIL INVESTIGATION WORK FOR CONSTRUCTION OF CHP AREA AT MINE S END

5 FIELD WORK 1. SELECTION OF BORE HOLES :- 1) 7,Nos number of bore hole was selected by the Engineer In Charge in order to obtain comprehensive sub-soil data for this site up to specified depth below G.L. For detailed laboratory investigation SPT is conducted in suitable intervals and Disturbed /undisturbed soil samples from the above bore hole were collected at different levels from as per the instruction of the client with observation of the ground water level during investigation. 2. BORING :- 2) The sub-soil exploration work at the proposed site was carried out using 150mm diameter rotary calyx rig boring equipments. 3. STANDARD PENETRATION TESTS :- 3) Standard penetration tests we are conducted in different levels in a continuous manner using a spilt spoon sampler. The SPT sampler was lower inside the bore hole after drilling the required level and is driven by a 65 kg. Hammer with a free fall of 750mm. In three stages 150mm each and the numbers of blows for each 150mm penetration was recorded. The details of location and SPT value [N] is shown in bore log data. 4. GROUND WATER TABLE :- 4) During the field work ground water level was observation in bore hole and the level of ground water table are shown in bore log data.

6 LABORATORY TESTS The laboratory tests were conducted on selected SPT / disturbed / undisturbed soil samples collected from the bore holes drilled at the proposed site. The tests include grain size analysis, natural moisture content, D.F.S specific Gravity, liquid limit, plastic limit, plasticity index test and shear test. Particles size distribution tests on representative soil sample were also carried out. The laboratory test confirming to the requirement of I.S and specification were conducted on the soil, sample. The results of all these tests are given in test result sheet separately. GRAIN SIZE ANALYSIS: The grain size analysis of different soil samples were done as per the requirement of IS: 2720(Pt- IV) 1975 method of test for soil, Grain size analysis. The details of the test results are shown test result sheet separately in tabular as well as graphically. The result of grain size analysis is used to classify the soil in various depths of bore holes. NATURAL MOISTURE CONTENT: The natural moisture content were determined as per IS: 2720(Pt II) 1973 Method of test for soil, determination of water content. DETERMINATION OF BULK DENSITY: The Bulk densities were determined in the laboratory from the UDS samples at different levels and the result are shown separately in tabular form. DETERMINATION OF DRY DENSITY: The dry density of the UDS/DS samples was determined at the known moisture content and bulk density. DETERMINATION OF SPECIFIC GRAVITY: The specific gravity of the UDS/DS sample was determined at different levels and the results are shown separately. DETERMINATION OF VOID RATIO: The void ratios of the UDS/DS samples were determined at different levels and the results are shown separately. LIQUID LIMIT & PLASTIC LIMIT: [AS PER IS : 2720 Pt IV] : The liquid and plastic limit of soils were other index properties of soil have also been determined as per the relevant IS code of practice. The liquid and plastic limits of soil samples have been determined in the laboratory and results are shown separately. DETERMINATION OF SHEAR PARAMETERS: Un consolidated and un drained Tri-axial shear tests were carried out from soil samples collected as per IS : 2720 Pt IX 1971 with three different cell pressures of 1,2,3kg/sq.cm using Tri axial shear testing machine and result are shown separately in tabular and graphical manner.

7 P R E F A C E The general soil profiles and the geological stratification have been determined OPGC PROPOSED FOR SOIL INVESTIGATION WORK FOR CONSTRUCTION OF CHP AREA AT MINE S END. The objective of this investigation is to ascertain the characteristics of Sub-soil to present necessary information for sub-surface. It was endeavored to study in detail the sub-surface conditions at the project site.. The field and laboratory works have been conducted as per relevant Bureau of Indian standards.

8 FIELD OPERATIONS In an attempt for optimization in the design of foundation for the proposed building to be constructed at this site, Geo-technical investigation was done. The entire investigation work had been divided mainly into two parts (i) Field Work & (ii) Laboratory tests Field work determines the types of sub- soil deposit and their characteristics. Laboratory tests help in determining the relevant geo-technical properties of the sub-surface deposited leading to finalization of foundation depth of the structure basing on Bearing capacities of the foundation strata as well as Influence zone SL. NO BORE HOLE NO. GROUND WATER TABLE & TERMINATION DEPTH GROUND LEVEL CHANAGE (M) TERMINATION DEPTH IN MTR. WATER TABLE FROM THE G.L IN MTR M 2.0 M M 2.2M M 2.0M M 3.0M M 1.80M M 2.2M M 2.3M BORING & SITU TESTS Wash boring method was adapted to bores in the soil up to specified depth as mentioned above below the G.L for BH -01 to 05 The SPT were conducted at regular intervals and the samples were brought to the laboratory with proper identification and labeling standard split spoon sampler was used for conducting standard penetration test. The number of blows required to drive the sampler for the 1 st, 2nd and 3 rd 15cm depths were recorded. The total number of blows required to drive the split spoon sampler due to the free fall of a 663kg. Hammer trough distance of 75cm for the 2 nd, and 3 rd 15cm penetration were taken together as the field N-value (penetration resistance) of the soil.

9 C Ф DS UDS NMC NP G G M C LL PL Pl Cc K UCS N BH Suffix Nc,Nq,Nγ Sc,Sq,Sγ γ D FS Cv UU CU GC GP GW SC SM SW SP CH Cl CL MH MI ML NOTATIONS Cohesion Angle of internal fraction of soil Disturbed Sample Undisturbed Sample Natural Moisture Content Non plastic soil Special gravity Gravel Content Slit Content Clay Content Liquid Limit Plastic Limit Plasticity index Compression index Coefficient of permeability Unconfined Compression SPT Value Bore Hole The Number of Bore Holes Bearing Capacity Factor S hape factors Density of soil Depth of foundation Factor of safety Coefficient of consolidation Unconsolidated untrained triaxial test Consolidated drained triaxial test Clayey Gravels Poorly Graded Gravels Well Graded Gravels Clayey Sand Silty Sand Wel Graded Sand Poorly Graded Sand Clays of High Plasticity Clays of Intermediate Plasticity Clays of Low Plasticity Slits of High Plasticity Silts of intermediate Plasticity Silts of Low Plasticity

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11 Sl. No. soil sample collected at Type of sample collected at Fine Gravel in % Coarse (10mm sand to in % (4.75mm to Medium 2.00mm) sand in % (2mm to 0.425mm) Fine sand in % (0.425mm to 0.075mm) Silt & Clay in % (0.075mm to 0.001mm) Liquid Limit in % Plastic Limit in % Plasticity Index in % Field Moisture Content in % Bulk Density in gm/cc. Dry Density in gm/cc. Cohesion (C) Kgf/cm² Angle of shearing resistance (Ø) In degree Specific Gravity Void Ratio D.F.S. in % Field S.P.T. value Group of soil \ Grain size analysis GUMUDAENGINEERING PROPERTIES OF SOIL PROJECT: SANGHUMUDA (BH NO- 6) Atterberg s Limits in % SPT SPT N P N P N P N P GM 41 GM 7.5M TO 8.0M CORE RECOVERY = 69% & RQD = 52% 8.0M TO 9.0M CORE RECOVERY = 74% & RQD = 62% 9.0M TO 10.0M CORE RECOVERY = 81 % & RQD = 70%

12 CADD CONSULTING ENGINEERS (P) LTD Bore hole no:-6 GEO - TECHNICAL INVESTIGATION & Sheet No :- 1 FOUNDATION ENGINEERING. NAME OF THE WORK : SOIL INVESTIGATION WORKS FOR SANGHUMUDA Data for the safe Bearing capacity calculation: (NonCohesive Soil) SPT 'N' = 28 unconfined compressive strength qu = N/7.5 kg/cm 2 Corrected = 22 C = qu/2 = 0.00 T/sq.m Depth = 1.5 M Ø = 33 degree Width = 2.0 M y t = 1.82 gm/cc Based on the above 'N' value the following ' Ø ' values are obtained from the fig.1 of the IS: less soils (C=0). And for cohesive soils ( Ø =0) the 'c' value is considered from the relation " Note:- Where ever the test results are not available the same was assumed based on the available values. If the Ø <29 the Local shear failure condition is to be considered and Ø>36 General shear failure condition is to be considered. LOCAL SHEAR FAILURE CONDITION Ø' = tan^ (-1)(0.67x tanø) = 23.0 Degree C' = 0.67C = 0.00 T/sq.m Specific gravity of soil at 1.5 m depth (G) AS PER IS : ,TABLE-1 = 2.62 (from lab test) Nc' = G = 2.62 Nq' = q = Yt X Df Nγ' = = 1.82 X 1.50 = 2.73 T/M² ` By = Width X Yt 2.0 X 1.82 = 3.6 T/M² AS PER IS : ,TABLE-2 Sc = 1.0 Sq = 1.0 Sy = 1.0 AS PER IS : , dc = 1.29 dq = 1.15 dγ = 1.15 (Since ø > 10) AS PER IS : , ic = 1 iq = 1 iγ = 1 W = 1.0 Assuming the depth factor, shape factor and load inclination factors as unity. Assuming the water table correction factor (W') as 1.0 the ultimate bearing capacity is calculated as below: Qult = (C NcSc dc ic)+y.d.(nq-1)sq dq iq+1/2 By NySy dy Iy W' = x x 1.0 x 1.29 x x 7.95 x 1.0 x 1.15 x x 3.6 x 8.58 x 1.0 x 1.15 x 1.0 x 1.0 = = T/M² Qult = T/sq.M Assuming the Factor of Safety as = 3 SBC = T/sq.m

13 NAME OF THE WORK : SOIL INVESTIGATION WORKS FOR SANGHUMUDA Data for the safe Bearing capacity calculation: (NonCohesive Soil) SPT 'N' = 41 unconfined compressive strength qu = N/7.5 kg/cm 2 Corrected 'N' = 28 C = qu/2 = 0.00 T/sq.m Depth = 3.0 M Ø = 35 degree Width = 2.0 M y t = 1.98 gm/cc 13 CADD CONSULTING ENGINEERS (P) LTD Bore hole no:-6 GEO - TECHNICAL INVESTIGATION & Sheet No :- 1 FOUNDATION ENGINEERING. Based on the above 'N' value the following ' Ø ' values are obtained from the fig.1 of the IS: for cohesion less soils (C=0). And for cohesive soils ( Ø =0) the 'c' value is considered from the relation " Note:- Where ever the test results are not available the same was assumed based on the available values. If the Ø <29 the Local shear failure condition is to be considered and Ø>36 General shear failure condition is to be considered. LOCAL SHEAR FAILURE CONDITION Ø' = tan^ (-1)(0.67x tanø) = 25.0 Degree C' = 0.67C = 0.00 T/sq.m Specific gravity of soil at 3.0 m depth (G) AS PER IS : ,TABLE-1 = 2.62 (from lab test) Nc' = G = 2.62 Nq' = q = Yt X Df Nγ' = = 1.98 X 3.00 = 5.94 T/M² ` By = Width X Yt 2.0 X 1.98 = 4.0 T/M² AS PER IS : ,TABLE-2 Sc = 1.0 Sq = 1.0 Sy = 1.0 AS PER IS : , dc = 1.58 dq = 1.29 dγ = 1.29 (Since ø > 10) AS PER IS : , ic = 1 iq = 1 iγ = 1 W = 0.5 Assuming the depth factor, shape factor and load inclination factors as unity. Assuming the water table correction factor (W') as 0.5 the ultimate bearing capacity is calculated as below: Qult = (C NcSc dc ic)+y.d.(nq-1)sq dq iq+1/2 By NySy dy Iy W' = x x 1.0 x 1.58 x x 9.66 x 1.0 x 1.29 x x 4.0 x x 1.0 x 1.29 x 1.0 x 0.5 = = T/M² Qult = T/sq.M Assuming the Factor of Safety as = 3 SBC = T/sq.m

14 CADD CONSULTING ENGINEERS (P) LTD BORE HOLE:-6 GEO - TECHNICAL INVESTIGATION & Sheet No : 1 FOUNDATION ENGINEERING. CALCULATION OF ALLOWABLE BEARING PRESSURE BASED ON SPT 'N' VALUE NAME OF THE WORK:SOIL INVESTIGATION WORKS FOR SANGHUMUDA ALLOWABLE BEARING PRESSURE FOR 40MM SETTLEMENT Width of footing (B) Depth of footing (D) Water table correction(w') = 2.0 m = 200 cm = 3.0 m = 300 cm = 0.5 m SPT 'N' VALUE OBSERVED = 41 Corrected N value Due to over burden pressure As per IS 8009 part I = 28 Settlement, For 1 kg/cm 2 Read from IS 8009 ( part I) 1976 Figure - 9, P.P-17 = m d = ( WT - D) = 9.00 mm (After applying W') d/b = 18 mm Adopted water table correction (W') Premissable settlement = 40 mm Therefore Allowable Bearing pressure = 40 / 18 = kg/cm 2 = T/m 2

15 CADD CONSULTING ENGINEERS (P) LTD BORE HOLE:-6 GEO - TECHNICAL INVESTIGATION & Sheet No : 1 FOUNDATION ENGINEERING. CALCULATION OF ALLOWABLE BEARING PRESSURE BASED ON SPT 'N' VALUE NAME OF THE WORK:SOIL INVESTIGATION WORKS FOR SANGHUMUDA ALLOWABLE BEARING PRESSURE FOR 25MM SETTLEMENT Width of footing (B) Depth of footing (D) Water table correction(w') = 2.0 m = 200 cm = 3.0 m = 300 cm = 0.5 m SPT 'N' VALUE OBSERVED = 41 Corrected N value Due to over burden pressure As per IS 8009 part I = 28 Settlement, For 1 kg/cm 2 Read from IS 8009 ( part I) 1976 Figure - 9, P.P-17 = m d = ( WT - D) = 9.00 mm (After applying W') d/b = 18 mm Adopted water table correction (W') Premissable settlement = 25 mm Therefore Allowable Bearing pressure = 25 / 18 = kg/cm 2 = T/m 2

16 CADD CONSULTING ENGINEERS (P) LTD BORE HOLE:-6 GEO - TECHNICAL INVESTIGATION & Sheet No : 1 FOUNDATION ENGINEERING. CALCULATION OF ALLOWABLE BEARING PRESSURE BASED ON SPT 'N' VALUE NAME OF THE WORK:SOIL INVESTIGATION WORKS FOR SANGHUMUDA ALLOWABLE BEARING PRESSURE FOR 40MM SETTLEMENT Width of footing (B) Depth of footing (D) Water table correction(w') = 2.0 m = 200 cm = 1.5 m = 150 cm = 1.0 m SPT 'N' VALUE OBSERVED = 28 Corrected N value Due to over burden pressure As per IS 8009 part I = 22 Settlement, For 1 kg/cm 2 Read from IS 8009 ( part I) 1976 Figure - 9, P.P-17 = m d = ( WT - D) = mm (After applying W') d/b = 12 mm Adopted water table correction (W') Premissable settlement = 40 mm Therefore Allowable Bearing pressure = 40 / 12 = kg/cm 2 = T/m 2

17 CADD CONSULTING ENGINEERS (P) LTD BORE HOLE:-6 GEO - TECHNICAL INVESTIGATION & Sheet No : 1 FOUNDATION ENGINEERING. CALCULATION OF ALLOWABLE BEARING PRESSURE BASED ON SPT 'N' VALUE NAME OF THE WORK:SOIL INVESTIGATION WORKS FOR SANGHUMUDA ALLOWABLE BEARING PRESSURE FOR 25MM SETTLEMENT Width of footing (B) Depth of footing (D) Water table correction(w') = 2.0 m = 200 cm = 1.5 m = 150 cm = 1.0 m SPT 'N' VALUE OBSERVED = 28 Corrected N value Due to over burden pressure As per IS 8009 part I = 22 Settlement, For 1 kg/cm 2 Read from IS 8009 ( part I) 1976 Figure - 9, P.P-17 = m d = ( WT - D) = mm (After applying W') d/b = 12 mm Adopted water table correction (W') Premissable settlement = 25 mm Therefore Allowable Bearing pressure = 25 / 12 = kg/cm 2 = T/m 2

18 CADD CONSULTING ENGINEERS (P) LTD. GEO - TECHNICAL INVESTIGATION & FOUNDATION ENGINEERING. BH NO :- 06 SHEET NO : 1 NAME OF WORK:- SOIL INVESTIGATION WORKS FOR SAGHUMUDA SITE SUMMARY OF GEOTECHNICAL PARAMETERS & SAFE BEARING CAPACITY BH DEPTH BGL NO (M) FOOTI NG IN M TYPE OF SAMPL E BULK DENSIT Y, SPT- N N CORREC TION gm/cc VALUE VALUE SHEAR PARAMETER C KG/CM 2 Ø DEGRE E ARRIVED SBC T/M² ALLOWABLE BERING PRESSURE FOR 25mm SETTELEMENT T/M² ALLOWABLE BERING PRESSURE FOR 40mm SETTELEMENT T/M² (2X2) SPT (2X2) SPT

19 CADD CONSULTING ENGINEERS PVT.LTD. GEO - TECHNICAL INVESTIGATION & FOUNDATION ENGINEERING. BH NO-06 LOCATION: - SANGHUMUDA DEPTH OF FOUNDATIO7.5 M TO 8.0 M AS PER CI.6 OF IS:12070 q s = q c x N j Where : q s = Safe Bearing Pressure (gross) q c = Average UCS of rock cores N j = Empirical coefficient Including FOS 3 N j = ( 3 + S / B f ) / (10 ( δ / S)) δ = Thickness of discontinues (cm) S = Spacing of discontinues (cm) Bf = Footing Width From table 4 of IS :12070 For spacing of discontinues from 30 cm to 100 cm From laboratory test data q c = 206 kg / cm 2 = 2060 T / M 2 q s = 2060 x 0 = 206 T / M 2 SBC is conservatively Restricted to 80 T / M 2 for designed purposed.

20 CADD CONSULTING ENGINEERS PVT.LTD. GEO - TECHNICAL INVESTIGATION & FOUNDATION ENGINEERING. BH NO-06 LOCATION: - SANGHUMUDA DEPTH OF FOUNDATIO8.0 M TO 9.0 M AS PER CI.6 OF IS:12070 q s = q c x N j Where : q s = Safe Bearing Pressure (gross) q c = Average UCS of rock cores N j = Empirical coefficient Including FOS 3 N j = ( 3 + S / B f ) / (10 ( δ / S)) δ = Thickness of discontinues (cm) S = Spacing of discontinues (cm) Bf = Footing Width From table 4 of IS :12070 For spacing of discontinues from 30 cm to 100 cm From laboratory test data q c = 211 kg / cm 2 = 2110 T / M 2 q s = 2110 x 0 = 211 T / M 2 SBC is conservatively Restricted to 80 T / M 2 for designed purposed.

21 CADD CONSULTING ENGINEERS PVT.LTD. GEO - TECHNICAL INVESTIGATION & FOUNDATION ENGINEERING. BH NO-06 LOCATION: - SANGHUMUDA DEPTH OF FOUNDATIO9.0M TO 10.0M AS PER CI.6 OF IS:12070 q s = q c x N j Where : q s = Safe Bearing Pressure (gross) q c = Average UCS of rock cores N j = Empirical coefficient Including FOS 3 N j = ( 3 + S / B f ) / (10 ( δ / S)) δ = Thickness of discontinues (cm) S = Spacing of discontinues (cm) Bf = Footing Width From table 4 of IS :12070 For spacing of discontinues from 30 cm to 100 cm From laboratory test data q c = 218 kg / cm 2 = 2180 T / M 2 q s = 2180 x 0 = 218 T / M 2 SBC is conservatively Restricted to 80 T / M 2 for designed purposed.

22 SOAKED UNSOAKE POROSITY (MG/(1+MG)X100 FOUNDATION ENGINEERING. SUMMARY OF FOUNDATION DETAILS OF ROCK SAMPLES LOCATION:-SANGHUMUDA BORE HOLE NO -06 ROCK IN T/M 2 (q s SL. NO BORE HOLE DEPTH OF FOUNDATION BGL (m) CORE RECOVERY % RQD % MOISTER CONTENT (%) SOUNDNESS HARDNESS (H,SCALE MOHS) POINT LOAD STRENGTH INDEX UNCONFINED COMPRESSION STRENGTH OF UNIT WEIGHT OF ROCK (g/cc) q u * N SLAKE UDRABILITY INDEX (10 mnts cycle) SPECIFIC GRAVITY J ) = CADD CONSULTING ENGINEERS PVT.LTD. GEO - TECHNICAL INVESTIGATION & 7.5m to 8.0m 8.0m to 9.0m 9.0m to 10.0m 69% 52% 0.30% 10.0% % 62% 0.31% 11.0% % 70% 0.33% 11.4% NOTE:- Nj = 0.1 qs= S.B.C OF ROCK IN T/M2 qs (qu) X Nj SBC is conservatively Restricted to 80 T / M2 for designed purposed.

23 CADD CONSULTING ENGINEERS PVT.LTD GEO-TECHNICAL INVESTIGATION & FOUNDATION ENGINEERING. Sheet No:1 BOREHOLE NO- 6 ANALYSIS OF THE SUB SOIL INVESTIGATION TEST RESULT LOCATION: -SANGHUMUDA BOREHOLE NO- 6 Borehole no- -6, was sunk up to an average depth of 10.0M the sub soil strata of the Borehole is given in litho logical form and summarized as follows. STRATUM The top layer up to an average depth up to 7.5 m consists of D.I rock.. The stratum below an average depth from 7.5 m to 10.0 m is consists of hard rock. The strata are moderately medium to very dense compact and low to medium plasticity. The SPT value tabulated in bore log data sheet. The core recovery was observed during investigation and tabulated in bore log data sheet. The ground water table was encountered at 2.2 m within boring depth.

24 FOUNDATION & RECOMMENDATION Considering the 7 no s of bore hole and after studying all the engineering properties it has been decided that depth of foundation can be taken in suitable depth by digging at least 1.5m inside rock from the original ground level both for economical point of view and for good structural stability.. But however the structural designer can adopt higher depth to take advantage of higher SBC depending upon the load as per decision of designer. The designer can study the ABP/SBC table for above borehole and take his own decision as per structural load and position of structure at the site. The settlement is negligible. Therefore no special care is required for footing. Single isolated RCC footing can be adopted for framed structure and for all types of structure. 1. All R.C.C works should be designed as per IS Shallow foundation will be designed as per IS: The groundwater table were encountered and tabulated in Bore log data in all bore holes.