SEGJ Technical Conference

Feasibility study of passive source surface wave method under the condition of high traffic vibration noises

Abstract The authors carried out a geophysical survey and data analysis using the 2 dimensional linear array microtremor survey method (2D-LAMS) on an earthen levee which was located along a heavily trafficked road. As the results, we had verified that 2D-LAMS had advantages in terms of its investigation depth and applicability under conditions of high levels of ground vibration noise (Kita et al, 2013). Using the same microtermor data obtained at the earthen levee with 2D-LAMS, we applied three data processing techniques, namely the Spatial Autocorrelation method (SPAC), the Tau-P transformation technique and the Seismic Interferometry (S.I.) technique, and then compared all three obtained dispersion curves. The dispersion curves obtained both by the Tau-P transformation technique and by the S.I. technique generally corresponded with those obtained by SPAC. It was suggested, however, that the phase velocities at low frequencies obtained by the S.I. technique would be faster than actual S-wave velocities. Neither the Tau-P transformation technique nor S.I. technique provided stable dispersion curves in comparison with SPAC which is used for 2D-LAMS. Consequently, we confirmed that 2D-LAMS is an advanced survey method as a passive source surface wave method, when the survey lines are set near busy roads.