SOIL CHARACTERIZATION OF JABALPUR CITY USING BORE LOGS

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1 ISSN IJESR/June 16/ Vol-6/Issue-6/ Mrinal Singh et. al., / International Journal of Engineering & Science Research SOIL CHARACTERIZATION OF JABALPUR TY USING BORE LOGS ABSTRACT Mrinal Singh* 1, Rakesh Grover, Dr.Shailza Verma 3 1 M.E. Scholar, J.E.C. Jabalpur, India. Associate Prof., Dept. of Civil Engineering, Jabalpur Engineering College, Jabalpur, India. 3 Assistant Prof. Dept. of Civil Engineering, Jabalpur Engineering College, Jabalpur, India Geotechnical engineering deals with the safe transmittal of loads due to various engineering applications to, and into, the soil or rock mass. The soil and rock mass formations are heterogeneous and generally are subjected to stresses (due to various engineering applications) which are additional to those presently existing in the earth mass from its self weight and geological history. Due to these earth mass properties, the amalgamation of experience, study of what others have done in somewhat similar situations and site specific geotechnical information are required to produce an economical, practical and safe substructure design. The correct interpretation of the results obtained from field exploration and laboratory tests is one of the most important crucial parts of geotechnical engineering. Geotechnical data of Jabalpur city, collected by JEC civil department for many years is in the raw format and numbers of tests are performed by us at different locations. To use all this data for future and in further construction works, this data should be organised in a suitable database. Therefore bore logs are established to convert data from the raw format and to facilitate the interchanging data among organizations. Bore log will manipulate and query effectively necessary information from geotechnical data. Keywords: Investigation, Bore logs, Geological Profile, Incumbent. INTRODUCTION Soil characterization provides the basic soil index property and engineering properties, which are determined based on in-depth exploration to identify and evaluate a potential hazard. Soil characterization involves investigation 1 (laboratory and field), data collection, interpretation of data and finally representing in terms of bore logs. Geotechnical soil characterization is usually done using experimental investigations of sieve analysis, liquid limit, plastic limit, water content, standard penetration test, cone penetration test, etc. Soil characterization is carried out with the following objective: (a) Measuring and the interpretation of soil properties (b) To evaluate the parameters of soil (c) To assess the engineering parameters and to estimate the safe bearing capacity of soil A general soil characterization should describe: (a) The soil (b) Soil description and location This data can thus be used to select a site, design the foundation and earthworks. Need for Soil Characterization: (a) There are uncertainties in the ground, as a result of natural and manmade processes, that may jeopardize a project and its environment if they are not adequately understood and mitigated. (b) An appropriate soil characterization will maximize economy by reducing, to an acceptable level, the uncertainties and risk that site conditions pose to a project. *Corresponding Author 131

2 (c) Soil characterization involves the determination of the nature and behaviour of all aspects of a soil and its environment that could significantly influence, or be influenced by, a project. (d) The basic purpose of soil characterization is to provide sufficient, reliable information of the soil conditions to permit good decisions to be made during assessment, design and construction phases of a project. (e) Soil Characterization should include an evaluation of subsurface features, sub surface material types, subsurface material properties. OVERVIEW Geotechnical engineering analysis and evaluation is valid only if the measured values are representative of in situ conditions. Properties of some materials are best measured in the laboratory, while others in field tests. Geotechnical investigation involves the following tasks - (a) Need to define the bedrock depth, which is very important as purpose of the geotechnical investigations is to assess the influence of local site conditions on the bedrock. (b) Define groundwater table conditions considering seasonal variations (c) Perform in situ testing and procure samples for laboratory testing. Various geotechnical tests including both in situ and laboratory tests are available for characterization. METHODOLOGY Jabalpur city is situated in the heart of M.P. It stands majestically on the tropic of cancer and on the banks of the river Narmada which flows through the white marble rock cluster site known for its beauty in the world. The city is located between 3º1' North latitude and 79º59' East longitude. Jabalpur city is spread over a total area of 367 sq. km average elevation of 11 meters (1,38 feet) above the sea level. Numbers of tests were performed by geotechnical department of JEC Jabalpur at different locations of city and many tests were performed by us at many locations. Data obtained from tests were in raw format to use it for future reference it should be preserved, this can be possible if we make bore logs of different locations using soil reports available in geotechnical lab and soil reports made by us. Bore logs obtained will describe soil profile of a definite area which can be used by different organizations for fulfilling their project requirements. Soil report obtained at the time of testing using all these procedures- Boreholes were terminated as per the direction. After positioning the rig at the specified location, for drilling through soil. Borehole was sunk by mechanically operated Cable Tool (Shell & Auger) in soil and rotary drilling in rock. Flush jointed steel casing tubes were provided to prevent possibility of side collapse in boreholes. After reaching the desired depth, depending upon the soil layer encountered, either Standard Penetration Tests & Vane Shear Tests were conducted or Undisturbed or disturbed soil samples were collected. The location of the boreholes is shown in the enclosed sketch. The field tests and sample collections were conducted in the boreholes in accordance with the relevant Indian Standard codes of practice and as per the following. (a) Standard Penetration Test in soils at regular depth intervals (b) Disturbed & Undisturbed soil samples FIELD INVESTIGATIONS (a) Standard Penetration Tests - Standard penetration tests (SPT) were carried out in soil within boreholes to determine strength characteristics of soil. This was carried out in accordance with IS: 131. The number of blows required to drive the standard split spoon sampler for penetration of.3 m by a 63.5 kg hammer falling freely from a height of 75 mm is recorded N Value at regular intervals in the borehole. If the sampler is not fully penetrating into soil, then the test was terminated after refusal noting the rate of penetration. (b) Sampling - Disturbed & Undisturbed representative soil samples were collected during investigations and subsequently sent to laboratory for visual examination and testing. The disturbed soil samples were also collected from split spoon sampler. Copyright 16 Published by IJESR. All rights reserved 13

3 LABORATORY INVESTIGATIONS All collected soil samples from the boreholes were brought to laboratory for necessary testing and rechecking the preliminary bore logs. The laboratory tests comprised of: (a) Grain Size distribution of all samples collected from boreholes- Grain size distribution was determined in two stages. The soil fraction retained on 75 micron IS Sieve was analysed by Sieve analysis using standard set of IS Sieve as prescribed by IS Sieve analysis is again done in two stages. The oven dried samples of soil was separated into two fractions by passing it through.75mm IS Sieve. The portion passing through the sieve was analysed by fine analysis using the IS Sieve Nos. mm, 1mm, 5, 5, 3, 1, 15 and 75 microns. The portion retained on this sieve was analysed by coarse analysis using IS Sieve Nos. 1, 6,, 1 and.75mm. (b) Atterberg Limits on all clay fractions- Liquid limit of the soil was determined by Casagrande method using Casagrande type mechanical liquid limit apparatus. Plastic limit was determined as per the standard procedure IS: 7(Part 5) (c) Natural moisture content- Natural moisture content of the soil was determined by oven drying method as per IS: 7 Part II, Weights were taken to an accuracy of.1gr. IS 198 (197) mentioned symbols and their usual meanings and details with hatching pattern and color code. Soil classification using group symbols is as follows: Group Symbol Coarse soils GW GP GM GC SW SP SM SC Fine soils ML MI MH CL CH OL OI OH Pt RESULT AN DISCUSSION Classification Well-graded GRAVEL Poorly-graded GRAVEL Silty GRAVEL Clayey GRAVEL Well-graded SAND Poorly-graded SAND Silty SAND Clayey SAND SILT of low plasticity SILT of intermediate plasticity SILT of high plasticity CLAY of low plasticity CLAY of intermediate plasticity CLAY of high plasticity Organic soil of low plasticity Organic soil of intermediate plasticity Organic soil of high plasticity Peat Generalised Geological Profile A generalised geological profile [3] is prepared for individual boreholes of different locations of Jabalpur. The description of the various layers is based on the laboratory test results based on IS classification. For the purpose of clarity, existing ground level is considered as.m, datum for boreholes in the individual geological profile. Figure showing bore logs of some of the location:- Copyright 16 Published by IJESR. All rights reserved 133

4 Mrinal Singh et. al., / International Journal of Engineering & Science Research NSCB MEDICAL COLLEGE B1 B P3 P SP SC SM DRP LINE B1 B 6 CL RICHHAI INDUSTRIAL AREA B1 B B3 B 6 8 CH COD B1 B SP In above figures, B1, B, B3, B- BORE LOGS SHOWING SOIL CHARACTERISTICS Depth meter Copyright 16 Published by IJESR. All rights reserved 13

5 CONCLUSION This paper may prove helpful for the research scholars and designers with the availability of soil characterization by using bore logs of different locations with the sufficient information at same time they can choose any of these data depending upon their quality control strategy. It must be remembered that geotechnical engineering is a highly specialised area of civil engineering and it is incumbent [] upon geotechnical agencies to take all care to use the data available in bore logs format with minimum ambiguities. REFERENCES [1] Anbazhaganp STG, Divya C. Site response analyses based on site specific soil properties using geotechnical and geophysical tests: correlations between G MAX and N 6, th international conference on earthquake geotechnical engineering paper no. 186, June 5-8, 7. [] Asaoka A, Nakano M, Noda T. Soil-water coupled behavior of heavily over-consolidated clay near/at critical state. Soils and Foundations 1997; 37(1): [3] Banik S. Determination Of Bearing Capacity Of Shallow Foundation On Dhaka Sub-Soil Using Sub Loading Tij Model. M Engg. Thesis, Department OfCivil Engineering, Bangladesh University Of Engineering And Technology, Bangladesh, July 1. [] Gupta S. Interpretation of geotechnical report, Indian geotechnical conference, December 1; [5] Gupta GP, Tembhare BR, Mishra SR. Characterization and Classification of Soils of Granitic Terrain In Jabalpur District of Madhya Pradesh. Agropedology 1999;9(): [6] IS Code of Practice for Site Investigation for Foundations, BIS, New Delhi. [7] Khouri NQ. Dynamic Properties of Soils, Master Thesis, Department Of Civil Engineering, Syracuse University, 198. [8] Luna R, Jadi H. Determination of dynamic soil properties using geophysical methods. Proc. of the First International Conference on the Application of Geophysical and NDT Methodologies to Transportation Facilities and Infrastructure, St. Louis, MO, December. [9] Lambe TW, Whitman RV. Soil Mechanics, John Wiley and Sons, New York, [1] Nakai T. Modeling of soil behavior based on tij concept. The 13 th Asian Regional Conference on Soil Mechanics and Geotechnical Engineering, Kolkata, India, December 1, 7. [11] Rashid MA. Seismic Microzonation of Dhaka City Based on Site Amplification and Liquefaction, M Engg. Thesis, Department of Civil Engineering, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh, 7. [1] Son le M. Compiling Geotechnical Data To Determine The Distribution And Properties Of Top Sand Deposits In Quadrant K & L Of The Dutch Sector North Sea, February. [13] Terzaghi K. Theoretical Soil Mechanics, John Wiley And Sons, New York, 193. [1] Terzaghi K, Peck RB. Soil Mechanics InEngineering Practice, (First And Second Edition), John Wiley And Sons, 198 & Copyright 16 Published by IJESR. All rights reserved 135

SOIL CLASSIFICATION OF JABALPUR CITY USING BORE LOGS

SOIL CLASSIFICATION OF JABALPUR CITY USING BORE LOGS 1 Mrinal Singh, 2 Rakesh Grover, 3 Dr. Shailza Verma 1 M.E. Scholar, Jabalpur Engineering College, Jabalpur, India 2, 3 Associate Prof. Dept. of Civil