||Recent strong earthquakes reveal that characteristics of ground vibration are affected by the shape and depth of the bedrock significantly. To predict the strong ground motions of a region thus require the information regarding the three dimensional distribution of the bedrock and soil layer of that region. |
Generally, in the prediction of the strong ground motions of a region, the rigorous analytical solution is formidable due to the complexity of the bedrock and soil layer and thus numerical methods are adopted. In this study, we use program FDM3D, which is a staggered-grid finite-difference method in combination with the parallel computing technique, to simulate the ground vibration response of the 3D elastic model.
For a site subjected to different sizes of earthquakes, the characteristics of ground vibration are different, indicating that using the result of small earthquake to predict the ground responses of strong earthquakes is not appropriate. This study also found the importance of the underground-structure for predicting the surface ground motions. It is recommended that the distribution of earthquake bedrock should be determined within a distance of 3 km in the vicinity of the desired region.
||Akamatsu, J., H. Saito, M. Jido, H. Morikawa, K. Nishimura, and M. Komazawa (1996). "Effects of irregular bedrock configuration in a sedimentary basin on ground vibration characteristics," proceeding of 11th World Conference on Earthquake Engineering, No. 1655.|
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