Joint analysis of shear wave velocity from SH-wave refraction and MASW techniques for SPT-N estimation

Abstract

Horizontally polarized shear wave (SH) refraction and multichannel analysis of surface wave (MASW) methods have been carried out in Hatyai City, southern Thailand, a pilot study for site classification, part of the National Earthquake Hazards Reduction Program (NEHRP). The objectives of this study are the comparison of the efficiencies of different shear wave velocity (Vs) determination techniques and the use of Vs measurements of the prediction of standard penetration resistance (SPT-N). Good correlation between all Vs profiles and SPT-N values and local lithology are observed. However, there are systematic differences between SH-refraction based-Vs and MASW based-Vs, which might be explained by possible converted waves, limitations of the assumptions used, poor quality of the acquired data, and limitations of the inversion procedures of the methods applied. From the integrated use of Vs from both methods an empirical formula to describe the correlation between Vs and SPT-N values has been proposed and can be used to estimate geotechnical parameters in areas where no borehole or geophysical investigation exist.

Keywords

• SH-wave refraction
• MASW
• SPT-N
• shear wave velocity
• seismics