DEVELOPMENT OF NEW MODIFIED EMPIRICAL CORRELATION OF SHEAR WAVE VELOCITIES WITH STANDARD PENETRATION RESISTANCE IN GUWAHATI REGION

Abstract

Information on shear wave velocities (VS) of soil deposits is required for solution of design earthquake motions, soil-structure interaction and wave amplification. Dynamic elastic moduli computed using shear wave velocities are used as input parameter in finite element programs for dynamic analysis of structures, for soil structure interaction and for assessing liquefaction potential of soil. There are several wave propagation tests namely; seismic cross-hole, down-hole, up-hole and Multi-channel Analysis of Surface Waves (MASW) which yield shear wave velocity but all most of them are expensive. This paper attempt to propose a general correlation between shear wave velocity and standard penetration resistance based on empirical research equations which had been established worldwide. It first reviews earlier development and current advancement of previous related studies. Short reviews had revealed that previous investigations are all site dependent studies which tend to be independent from other researchers. Most of the researchers attempted to quantify the relation between shear wave velocity and standard penetration resistance at local scale for various countries in past few decades, others tried to correlate in terms of various soil indexes including depth, geological epoxy etc. Although numerous researchers had studied the correlation regression through empirical data, there is no concrete evidence to plot the range boundary of the regression correlations. Most researchers are in consensus to use a power-law form in describing the relationship between shear wave velocity and standard penetration resistance. This study propose new empirical correlation of VS and SPT-N values that has been generated based on statistical analysis of earlier published correlations which is applicable to all soil type.