Shear wave velocity Vs is measured by the surface geophysical survey like MASW (multi-channel surface wave analysis) or RWM (refraction wave method) and by the subsurface method like PS logging. PS logging and RWM...Shear wave velocity Vs is measured by the surface geophysical survey like MASW (multi-channel surface wave analysis) or RWM (refraction wave method) and by the subsurface method like PS logging. PS logging and RWM are direct methods to derive shear wave velocity and MASW retrieves shear wave through the inversion of the surface wave. In this work, the effectiveness of surface methods (MASW and RWM) is compared with PS logging in determining shear wave velocity. For this purpose, shear wave velocity results Vs30 of 12 PS logging and MASW surveys conducted in Mymensingh Municipality in Bangladesh have been utilized. Additionally, the shear wave velocity results of three PS logging have been compared with the refraction profiles of RWM survey conducted in Rooppur nuclear power plant site in Bangladesh. The relative discrepancy between RWM and PS logging is found less (ranges from -3.92 to 0.93) compared to MASW and PS logging (+/-0.88 to 33.92). The correlation coefficient of Vs30 derived from RWM and PS logging is observed much better (0.60) compared to MASW and PS logging (0.40). The result is good considering the lateral lithologic variability and inherent differences among techniques. It is evident from the comparison that the RWM can be used as a cost-effective alternative to traditional borehole PS logging method for Vs30 determination and thus the number of down-hole logging tests might be significantly reduced.展开更多
文摘Shear wave velocity Vs is measured by the surface geophysical survey like MASW (multi-channel surface wave analysis) or RWM (refraction wave method) and by the subsurface method like PS logging. PS logging and RWM are direct methods to derive shear wave velocity and MASW retrieves shear wave through the inversion of the surface wave. In this work, the effectiveness of surface methods (MASW and RWM) is compared with PS logging in determining shear wave velocity. For this purpose, shear wave velocity results Vs30 of 12 PS logging and MASW surveys conducted in Mymensingh Municipality in Bangladesh have been utilized. Additionally, the shear wave velocity results of three PS logging have been compared with the refraction profiles of RWM survey conducted in Rooppur nuclear power plant site in Bangladesh. The relative discrepancy between RWM and PS logging is found less (ranges from -3.92 to 0.93) compared to MASW and PS logging (+/-0.88 to 33.92). The correlation coefficient of Vs30 derived from RWM and PS logging is observed much better (0.60) compared to MASW and PS logging (0.40). The result is good considering the lateral lithologic variability and inherent differences among techniques. It is evident from the comparison that the RWM can be used as a cost-effective alternative to traditional borehole PS logging method for Vs30 determination and thus the number of down-hole logging tests might be significantly reduced.