| dc.description.abstract | The strong motion records observed by KAU stations during the period from 1993 to 1998, which were collected by the Taiwan Strong Motion Instrumentation Program (TSMIP) of CWB, are adopted in this research. The single station spectral ratio method was used in this study to analyze the site effect in the area of southwestern Taiwan. Therefore, we can do the site classification from the H/V spectral ratio of response spectrum. The objective of this research is to provide the information of site category for the seismic loss estimation program, Haz-Taiwan. Furthermore, the analyses of site effects can be taken as reference for the seismic resistance designs and do favors to reducing damages and disasters resulted from earthquakes.
In this research, we obtained the frequency ranges and curve models of the B, C, D, and E types, and describe them as the following: (1) The Type B curve of H/V response spectral ratio has a smaller value between 0.5 and 2Hz, but gets larger values after 2Hz. Moreover, it has a peak around 5Hz. (2) The Type C curve is similar to that of Type B, but has its peak at around 3Hz. (3) The peak of Type D curve only exhibits between 2 and 3Hz, and its ratio is obviously bigger than those of Types B and C. (4) Type E curve has its peak at around 1.3Hz, and the ratio is smaller than that of Type D. Moreover, it has a wider frequency bandwidth than Type D around the peak.
From the contour of the H/V Fourier spectrum ratio at different frequencies, we got the following conclusions: (a) Between Taliao and Pingtung: it has obvious site amplification exists from 0.3 to 1Hz. (b) Near the seacoast of Pingtung Champaign, obvious magnification of the site effect exists from 0.1 to 2 Hz, and that above 2Hz the contour high area gradually move toward the inland. (c) The thickness of accretion in Pingtung Champaign is getting deeper from the direction of northeast toward southwest. (d) Close to Chienjen and Hsiaokang in Kaohsiung City, there has obvious site amplification effect exists from 0.5 to 1.5Hz. | en_US |