Calculating Liquefaction Potential of Northern Mississippi Using Shear Wave Data

Abstract

The potential for liquefaction can be determined using the Liquefaction Potential Index (LPI). The LPI takes into account the thickness of the liquefiable layers and the factors of safety with respect to depth. This study creates a hybrid method for determining the LPI for different locations in Northern Mississippi. It calculates an average CSR for the region using existing borehole information. The CRR is then calculated using shear wave velocity profile data from a MASW survey. The LPI obtained from this process is compared to LPI values calculated using CPT data and borehole shear wave data. Surface shear wave velocity profiles are measured near two existing borehole locations, TNA013 and TNA012. The sites near borehole TNA013 and TNA012 areboth very highly liquefiable according to the MASW method, but are only highly liquefiable using the borehole shear wave method.The LPI value calculated using CPT data near borehole TNA013 is classified as highly liquefiable and the LPI value near borehole TNA012 is classified as having a low liquefaction potential. The hybrid method gives a more conservative estimate of the liquefaction potential in the study area than the CPT method or borehole shear wave data