Evaluation of Liquefaction Potential of Nagpur Region Using SPT Data: Field Assessment

Abstract

Liquefaction is a complex, controversial but important topic in the Geotechnical engineering especially in earthquake sensitive regions. This secondary effect of earthquake causes severe damage to infrastructure. Nagpur is third largest and fastest growing and developing city in Maharashtra. The main aim of this study is to map the Nagpur city in the view of liquefaction potential occurrence and to make readily available data for further use and research. SPT-N based method is used for liquefaction assessment of soil encountered in the Nagpur region during investigation. The liquefaction potential is assessed regarding component of factor of safety (FS) along the depth of different soil stratum encountered during investigation. This liquefaction potential is evaluated at 56 representative sites in the city using Standard penetration tests (SPT) conducted and recorded in bore holes. Present study for computing liquefaction potential shows sensitivity in computing liquefaction against the SPT blow count and peak ground acceleration. For estimating Cyclic Resistance Ratio (CRR), the SPT-N value is corrected which indicates that the soil in the region is not identical at all locations, water table is of fluctuating nature and N values are varying according to soil properties but are mostly on higher sides which means that liquefaction potential is much low.