HR: 0800h
AN: S11A-0263    [Abstracts]
TI: Seismic Hazard Characteristics Derived from Ground Motion Simulation
AU: * zhao, z
EM: zhaozx1010@yahoo.com.cn
AF: Institute of Geology, Chinese Academy of Geological Science, Baiwanzhuang Road 26, Beijing, 100037, China
AU: Xu, J
EM: xujiren1125@yahoo.com.cn
AF: Institute of Geology, Chinese Academy of Geological Science, Baiwanzhuang Road 26, Beijing, 100037, China
AU: zhao, z
EM: pete74_1999@hotmail.com
AF: Department of Civil and Environmental Engineering University of Connecticut, 261 Glenbrook Rd., UNIT-2037, Storrs, CT 06269-203, United States
AB: Discrete numerical simulation for wave equation has been widely employed in study on the seismic wave propagation and strong ground motion in heterogeneous media by using the pseudospectral method with staggered grid RFFT differentiation (SGRFFTD) with different source models. Some characteristics of seismic hazard derived from ground motion simulations may benefit the disaster prevention and mitigating hazard. The simulation results show that the geophysical structure strongly affects the distribution of maximum amplitudes of seismic waveforms and the seismic damage. The amplification effects of shallow sedimentary layers vary with the sites at the surface. The influences on ground motions from seismological dynamic characteristics of the medium structure were analyzed. The influences upon the amplitudes of seismic waveforms by sedimentary layer were analyzed employing the soil core samples. Amplification effects of soil core samples of ten drill holes with 40 m deep are quite different among the sites. The maximum rate is 3.123, displaying soil amplified effect. The minimum is 0.864, displaying reduced effect. Such ratios display the nonlinear property of amplification effect of sediments in the heavily damaged zone too. The simulation results of seismic wave propagation in a basin structure using SGRFFTD show that the seismic energy transmitted into a sediment-filled basin from the bedrock may not refract back into the rock region. The seismic energy converted into the energy of the oscillations of the medium within the basin. The seismic wave oscillating up and down within the basin may result in large damage to the buildings. It is a notable characteristic in aseismic research. Ground motion simulation shows that interference between the body wave and the secondary surface wave occurring nearly the basin result in peak ground motions and high collapse ratios of buildings away from the earthquake fault. The interference strongly affects the distribution of maximum amplitudes of seismic waveforms and the seismic damage in the surface and around the basin and dam structure.
DE: 3285 Wave propagation (0689, 2487, 4275, 4455, 6934)
DE: 4260 Ocean data assimilation and reanalysis (3225)
DE: 7212 Earthquake ground motions and engineering seismology
SC: Seismology [S]
MN: 2007 Fall Meeting