|
| Seismic response analysis of soil layer under uniform excitation |
| Revised:September 26, 2003 |
| View Full Text View/Add Comment Download reader |
| DOI：10.7511/jslx20055111 |
| KeyWord:seismic response,uniform excitation,artificial boundary,exciting source in soil region,exciting source out of soil region |
| PAN Dan-guang~1 LOU Meng-lin~ |
|
| Hits: 1481 |
| Download times: 16 |
| Abstract: |
| When applying direct Finite Element Method(FEM) to analyze seismic response of soil layer,finite region of soil layer is used approximately to simulate the half-infinite soil layer.In order to eliminate the influence of the artificial boundary on the seismic response of soil layer,several different types of artificial boundaries were developed.Usually these artificial boundaries were based on the assumption that the dynamic exciting source is located in the analytical soil region.However,in the problem of seismic response analysis of soil layer by direct FEM,the seismic source is out of the soil region.Therefore,the influences of the artificial boundary on the seismic response of the soil layer include not only the wave reflection on the artificial boundary but also the reduction of excitation scope.It is a more complicated problem.In this paper,the effects of some artificial boundaries,such as free boundary and Lysmer's viscous damping boundary,are studied.Several influence parameters such as exciting frequency,soil damping and the ratio between width and depth of the cut soil layer is discussed by numerical examples based on linear visco-elastic assumption.From numerical results,it is concluded that the ratio between width and depth of the cut soil layer is the major influence parameter to determine the scope of soil layer and viscous damping boundary is not effective in the problem discussed in this paper.The reasonable ratio between width and depth of the cut soil layer is suggested.Based on above conclusion,the response of a river-crossing topography under seismic excitations was analyzed.The results showed that the scope of cut soil layer is satisfied. |
|
|
|