레일리파 분산을 역산하여 구한 횡파속도를 이용한 춘천시의 부지특성 = Site Characterization using Shear-Wave Velocities Inverted from Rayleigh-Wave Dispersion in Chuncheon, Korea

다국어 초록 (Multilingual Abstract)

To reveal and classify site characteristics in densely populated areas in Chuncheon, Korea, Rayleigh-waves were recorded at 50 sites including four sites in the forest area using four 1-Hz velocity sensors and 24 4.5-Hz vertical geophones during the period of January 2011 to May 2013. Dispersion curves of the Rayleigh waves obtained by the extended spatial autocorrelation method were inverted to derive shear-wave velocity (vs) models comprising 40 horizontal layers of 1-m thickness. Depths to weathered rocks (Db), shear wave velocities of these basement rocks (vbs), average velocities of the overburden layer (vss), and the average velocity to a depth of 30 m (vs30), were then derived from those models. The estimated values of Db, vbs, vss, and vs30 for 46 sites at lower altitudes were in the ranges of 5 to 29 m, 404 to 561 m/s, 208 to 375 ms/s, and 226 to 583 m/s, respectively. According to the Korean building code for seismic design, the estimated vs30 indicates that the lower altitude areas in Chuncheon are classified as SC (very dense soil and soft rock) or SD (stiff soil). To determine adequate proxies for vs30, we compared the computed values with land cover, lithology, topographic slope, and surface elevation at each of the measurement sites. Due to a weak correlation (r = 0.41) between vs30 and elevation, the best proxy of them, applications of this proxy to Chuncheon of a relatively small area seem to be limited.

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