@ ŒfÚŽGŽi˜ajF “ú–{’nkHŠwƒVƒ“ƒ|ƒWƒEƒ€˜_•¶W VolF 9-1Šª ”NF 1994”N •ÅF 163-168•Å ’˜ŽÒi˜ajF Žž¼@FŽŸC@Vˆä@—mC@Žðˆä@–çC@’‡žŠ@—L“ñ ƒ^ƒCƒgƒ‹i˜ajF ”÷“®‚̃AƒŒƒCŠÏ‘ª‚©‚焒肵‚½‹ú˜H‹CÛ‘ä‚Æ‹ú˜H`˜p‚Ì’n”Õ“Á«‚Æ’nk“®“Á« ´˜^i˜ajF
- ƒL[ƒ[ƒhi˜ajF - ŒfÚŽGŽi‰pjF PROCEEDINGS OF THE JAPAN EARTHQUAKE ENGINEERING SYMPOSIUM ’˜ŽÒi‰pjF Kohji TOKIMATSU, Hiroshi ARAI, Junya SAKAI, Yuji NAKAJO ƒ^ƒCƒgƒ‹i‰pjF SOIL CHARACTERISTICS AND EARTHQUAKE GROUND MOTIONS AT KUSHIRO JMA AND KUSHIRO HARBOR ESTIMATED FROM ARRAY OBSERVATION OF MICROTREMORS ´˜^i‰pjF
Possible use of microtremors is explored for estimating the effects of subsurface soil conditions on ground motion characteristics. For this purpose, microtremor measurements are conducted using arrays at two sites (Kushiro JMA and Kushiro Harbor) where strong motion accelerograms are available for the same earthquake. Based on F-K spectrum analysis, dispersion curves of Rayleigh waves for the sites are determined, which result in shear wave velocities down to depths of 400 m. With these profiles, the spectrum ratio of ground surface motions at two sites is estimated. The spectrum ratio shows fairly good agreement with that of the observed records. ƒL[ƒ[ƒhi‰pjF - ‹LŽ–‹æ•ªF - ‹æ•ª @@@ˆÏˆõ‰ï˜_•¶W