VALIDATION OF SPAC AND HVSR METHODS, AN EXPERIMENTAL STUDY
Supervisor: Toshiaki YOKOI
Pakistan is an earthquake prone country. A wide area including major cities is covered by thick sediments and the amplification of seismic waves is likely to occur. Studies to estimate velocity structure and amplification ratios in sedimentary layers in various parts of country are necessary. The microtremor can be considered as a dominant tool for estimating the earthquake site response. Therefore, the two methods, i.e., SPAC and HVSR, selected to carry out the present study are mainly based on microtremor. This study was carried out to check the validity of these microtremor methods. The focus was on the estimation of subsurface shear wave velocity structure and the calculation of the resonant frequency and/or the amplification of seismic waves in sedimentary layers. Velocity structures estimated by SPAC method were reliable and fairly accurate. The HVSR curve corresponded to the resonant frequency of the thick sediments but no clear relationship was found between this ratio and the amplification of waves.
|Citation: ||Bulletin of IISEE, 45, 37-42.|