ISSN 2394-3777 (Print) ISSN 2394-3785 (Online) Available online at www.ijartet.com International Journal of Advanced Research Trends in Engineering and Technology (IJARTET) Vol. 4, Issue 10, October 2017 All Rights Reserved © 2017 IJARTET 28 Experimental Study to Correlate Soaked CBR with Index and Engineering Properties of Black Cotton Soil of Madhya Pradesh Pravin Kumar Kushwaha 1 , Hemant Kumar Mahiyar 2 M.E. Transportation Engineering, CE & AMD, S.G.S.I.T.S. Indore, Madhya Pradesh, India 1 Professor, CE & AMD, S.G.S.I.T.S. Indore, Madhya Pradesh, India 2 Abstract: California Bearing Ratio is main design input in pavement construction to predict the shear strength and stiffness modulus of subgrade materials. Technically, the California Bearing Ratio value can be carried out in the laboratory or in the field. But due to time consuming and high cost for conventional CBR testing, prediction of the CBR value from other geotechnical properties of soil become profitable. In the present study, soaked value of CBR has been correlated with index and engineering properties for black cotton soil. The empirical correlation has been developed among the test results using Simple and Multiple Linear Regression Analysis from thirty five numbers of black cotton soil samples collected from eight districts of Madhya Pradesh, India. The soil properties studied are Specific Gravity, Liquid Limit, Plastic Limit, Free Swell Index, Unconfined Compressive Strength and Swelling Pressure are correlate with soaked CBR. Also, relationships for prediction of Unconfined Compressive Strength and Swelling from index properties were observed using simple and multiple linear regression analysis. Keywords: CBR, UCS, SP, LL, PL, FSI, Correlation, Regression. I. INTRODUCTION Presently the infrastructure of India’s is growing rapidly. In Civil Engineering works like the construction of highways, buildings, dams and other structure, proper analysis of the soil is important to ensure that these structures are safe and free from endue settling and fall. Soil formation and character are complex in nature and varies from place to place and over the time, therefore the exact prediction of its engineering behavior is in the interest of civil engineering field. The California Bearing Ratio (CBR) is a general and comprehensive test prevalent in the design of the pavements to evaluate the shear strength and stiffness modulus of subgrade materials to determine the thickness of the overlaying pavement layers. This test has been used for the decades and is familiar with the parties involved in the interpretation of the result, as a road design and construction. Civil Engineers in road construction always face difficulties in obtaining representative California Bearing Ratio value for the design of the pavement. Soil type is not the only parameter that affects the CBR value, but also varies with the soil properties obtained by the soil. The California Bearing Ratio (CBR) is an indirect measure, which represents the comparison of strength of subgrade, sub-base and base course materials to the strength of the standard crushed rock quoted in percentage value. This method was originally developed by the California Division of Highway in 1930’s as part of its study on pavement failure during World War II to assess the relative stability of fined rock material. Laboratory CBR testing requires a relatively large effort to carry out the test and is time consuming. The alternative method could be correlating the test results of CBR value with index and engineering properties of soil. These tests are more economical and faster than the CBR test . Several attempts have made on the prediction of the California Bearing Ratio (CBR) value from the other geotechnical properties of soil. Therefore, determining factors that affect the soil strength and deriving their relation with the CBR value in the representative sample may be considered as a good idea of soil behavior. The present experimental work shall provide an overview to get correlation between CBR value with index and engineering properties of soil. Previous researches and investigation in the correlation of CBR with the other geotechnical properties of Black Cotton soil is limited to only particular districts and inadequate number of sample. Hence, objective of present research is focused on increasing the study area and number of samples. At present, many projects of roads and railway constructions are undergoing in India. In light of it, the developed correlation will be useful to provide to the road authority, railway authority, contractors and consultant for the