REPORT ON SOIL INVESTIGATION FOR CONSTRUCTION OF PROPOSED 33/11 KV SUB STATION AT JAUN SAMANA, MARIPAT, GREATER NOIDA IN UTTAR PRADESH

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1 REPORT ON SOIL INVESTIGATION FOR CONSTRUCTION OF PROPOSED 33/11 KV SUB STATION AT JAUN SAMANA, MARIPAT, GREATER NOIDA IN UTTAR PRADESH CLIENT M/S NOIDA POWER COMPANY LTD. GREATER NOIDA FEBRUARY-2018 PREPARED BY SANGUINE CONSULTANTS RZ-456/13, TUGLAKABAD EXTENSION NEW DELHI PH: ,

2 LIST OF CONTENTS SL.NO. PARTICULARS PAGE NO. 1. INTRODUCTION SCOPE OF WORK FIELD INVESTIGATION METHODOLOGY LABORATORY TESTING LITHOLOGY FOUNDATION ANALYSIS 06 & DISCUSSIONS 7. CONCLUSIONS & RECOMMENDATIONS LAB.TEST RESULTS 11 (TABLE-01 TO TABLE-02) 9. ERT DATA 13 (TABLE-03 TO TABLE-04) 10. SIEVE ANALYSIS CURVE 15 (FIG.- 01 TO FIG.-02) 11. SHEAR CURVES 17 (FIG.-03 TO FIG-04) 12. SITE PLAN 19 (FIG.-05 )

3 1.0 INTRODUCTION M/s N.P.C.L., Greater Noida is planning to costruct 33/11 KV Sub-station at Jaun Samana, Maripat, Greater Noida in Uttar Pradesh. For a detailed design & engineering of proposed tower, the work of sub-soil investigation has been awarded to M/s Sanguine Consultants, New Delhi. The report presents the compiled data of test results of geotechnical investigation. The observed data of field investigations and laboratory tests are presented and uses to access the nature of subsoil strata and to evaluate the soil parameters required for the detailed design and engineering of proposed structure. THE SITE The site is located at Jaun Samana, Maripat, Greater Noida in Uttar Pradesh. The site is developed, leveled and drained. The informations & recommendations are given with respect to existing ground level at particular points rather than the reference level.

4 2. SCOPE OF WORK In order to establish the sub-soil characteristics of the area marked for construction of proposed sub-station, the entire investigation programme has been divided into field and laboratory tests leading to preparation of comprehensive report on the recommendations for foundation types and the corresponding design bearing capacity values for the foundations of proposed structure at the site. As mentioned within the framework of this job contract, the field investigations comprised of the following :- a) Boring of two (02) boreholes of 150mm dia. up to the depth of 10m or refusal whichever encountered earlier. b) Collection of representative disturbed and undisturbed soil samples, 100mm in diameter, from the exploratory bore holes for detailed laboratory analysis. c) Carrying out standard penetration tests as per IS: in each bore hole and subsequently preparation of penetration charts depth-wise for each bore hole. d) Conducting two (02) no. of Electrical Resistivity Tests at site as per marked in drawing.

5 The laboratory tests part of this job contract comprised of the following:- i) Grain size analysis a) Sieve analysis b) Hydrometer analysis ii) iii) iv) Liquid limit & plastic limit. Specific gravity Natural moisture content v) Bulk density & dry density vi) vii) viii) Direct shear tests on granular soil samples Unconsolidated undrained triaxial shear test Consolidation test

6 3.0 FIELD INVESTIGATION METHODOLOGY 3.1 DRILLING OF BOREHOLE Boreholes of 150mm diameter has been conducted by using shell and auger method up to the depth of 10.0m as per IS:1892 at proposed site location. The details of the soil type, type of sample collected and SPT N -value are shown in Table-01 to Table COLLECTION OF UNDISTURBED SOIL SAMPLES Undisturbed soil samples have been collected at 1.50m/3.0m interval in thin wall sampling tubes of 45cm long with area ratio less than of 10%. All undisturbed soil samples were collected by open drive tube sampler as per IS:2132 and the tube so recovered with samples, after removal of loose disturbed soil, were sealed by wax from both end to protect against the loss of moisture. After sealing, the sampling tubes were marked for testing of sample for various parameters. 3.3 STANDARD PENETRATION TEST Standard Penetration tests have been conducted as per IS:2131 in the borehole at interval of 1.50m or at the change of strata, wchichever encountered earlier. The penetration resistance (SPT) is expressed as number of blows required for 30 cm. on a rigid steel head and standard A rod attachment. The bottom of borehole have been cleaned before commencement of test. Also seating number of blows of 150mm were recorded before recording actual SPT N for 30 cm penetration. On removal of sampler, the soil entrapped in the sampler is taken out and the representative disturbed soil sample is preserved in polythene bags to avoid any loss of fines and marked for identification.

7 4.0 LABORATORY TESTING 1. The laboratory test was carried out after all the samples have reached the. 2. All samples brought from field, whether disturbed or undisturbed was extracted/prepared and examined by competent technical personnel, and the test was carried out as per the procedures laid out in the latest edition of the relevant I.S. Codes. The following laboratory test has been carried out i) Grain size analysis a) Sieve analysis b) Hydrometer analysis ii) Liquid limit & plastic limit. iii) Specific gravity iv) Natural moisture content v) Natural density vi) Drained direct shear test. vii) Unconsolidated undrained triaxial shear test All the above tests were conducted as per the provisions laid down in the relevant IS Code of practice. The test results for all the samples tested have been tabulated in proper format as shown in Table No.01 to Table-02.

8 5.0 LITHOLOGY Two boreholes drilled down to a depth of 10.0m reveals that the entirqe stratum consists of two Lithounits (layers), namely Lithounit-X and Lithounit-Y. LITHOUNIT-X Lithounit-X is light brown sandy silt with gravels starting from G.L. to 2.5m/2.50m depth of boreholes. Soil classification shows that this lithounit is low-plastic of CL in nature. Standard penetration test conducted in the boreholes indicate that the strata is stiff to very stiff in nature. Specific gravity of soil particles is found from 2.66 to LITHOUNIT-Y Lithounit-Y is light brown silty sand starting from 2.0m/2.50m to the depth of boreholes. Soil classification shows that this lithounit is non-plastic of SM in nature. Standard penetration test conducted in the boreholes indicate that the strata is medium dense in nature. Specific gravity of soil particles is found from 2.62 to FOUNDATION ANALYSIS AND DISCUSSIONS Two boreholes drilled down to a depth of 10.0m and disturbed/ undisturbed soil samples have been collected for laboratory testing. Standard Penetration Tests have been carried out as per I.S. standard. On the field investigation data, it is found that soil is stiff to very stiff to medium dense in nature. Open foundation is suggested.

9 6.1 GENERAL A suitable foundation for any structure should satisfy two basic criteria. Firstly, the soils should have adequate shear strength to support the superimposed loads so that there is an adequate safety factors against the bearing capacity. Secondly, the settlement of the soils including immediate elastic settlement and long terms consolidations settlement should be within the tolerable limits for the structure. The net allowable bearing pressure on the foundations should be taken as the lower of the two values obtained from these two criteria. 6.2 FOUNDATIONS TYPE In general, light to medium loaded structure may bear an open shallow footings. Heavily loaded structure may bear on raft foundation. 6.3 OPEN FOUNDATION Isolated/Raft foundation are feasible foundation schemes. Bearing capacity analysis for the shallow foundation is in accordance with IS Considering the presence of water level at 8.0m depth, a water table correction factor has been taken into account. A safety factor of 2.50 has been considered in the analysis as per IS Settlement analysis has been performed in accordance with IS:8009 part I. For computation of foundation settlement in average lower bound corrected N value has been used. A tolerable total settlement of 50mm and 75mm for Isolated and Raft foundation has been considered as per IS:1904.

10 6.3.1 SHEAR CONSIDERATION As per IS: ,the net ultimate bearing capacity can be calculated as: qu = 2/3CNc 1 Scd c i c + q (Nq 1 1) Sq dq iq Br Nr 1 Sr dr ir W 1 At 1.50m depth C = 5.50T/M 2, φ = 6 o, φ 1 = 4 o, Nc 1 = 6.22, Nq 1 = 1.456, Nr 1 = 0.36, r = 1.72 T/M3, Sc=1.3, Sq=1.2, Sr=0.8, w=0.5, FOS = 2.5. Qu = 2/3x5.50x6.22x x1.5x0.456x Bx1.72x0.36x0.8x0.5 = B for 1mx1m - qa = T/M 2 2mx2m - qa = T/M 2 3mx3m - qa = T/M 2 6mx6m - qa = T/M 2 At. 2.0m. Depth Qu = B for 1mx1m - qa = T/M 2 2mx2m - qa = T/M 2 3mx3m - qa = T/M 2 6mx6m - qa = T/M 2

11 6.3.2 SETTLEMENT CONSIDERATION Net safe bearing capacity on settlement criteria is calculated as per IS: 8009(PART-1) A tolerable total settlement of 50mm and 75mm for Isolated and Raft foundation has been considered as per IS:1904. At 1.50m Depth for size 2mx2m Average corrected N value below base of footing = 15 Settlement from the Fig.9 of IS:8009 (Part-I)-1976 = 20mm under net pressure intensity of 10 T/M2 Therefore, for a specified permissible settlement of 50mm, the net safe bearing capacity = (10 x 50) /(20 x 2 ) = T/M 2. At 2.0m Depth for size 2mx2m Average corrected N value below base of footing = 16 Settlement from the Fig.9 of IS:8009 (Part-I)-1976 = 18 mm under net pressure intensity of 10 T/M 2. Therefore, for a specified permissible settlement of 50mm, the net safe bearing capacity = (10 x 50) /(18 x 2 ) = T/M 2.

12 7.0 CONCLUSIONS AND RECOMMENDATIONS Based on field and laboratory investigations, following recommendations can be made: 1. As per field data & lab. Results, the entire stratum consists of two Lithounits (layers). Detail is shown in article Based upon SPT value & density, the soil strata is found stiff to very stiff to medium dense in nature. 3. It is suggested that the net allowable bearing capacity for Isolated footings may be taken as the table given below : NET ALLOWABLE BEARING CAPACITY IN T/M 2 Depth (m) 1Mx1M 2Mx2M 3Mx3M from EGL 1.50 m m Raft foundation may be designed as net allowable bearing capacity of 11.0 T/M 2 and 12.0 T/M 2 at 1.50m and 2.0m depth from EGL respectively. 5. Water level was encountered at 8.0m depth during the field investigation which may rise/fall with climatic condition. 6. For resistivity of soil, refer Table-03 to Table-04. For SANGUINE CONSULTANTS M.K.SINGH. (M.E., Geotech)

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