离心机振动台试验叠环式模型箱边界效应

针对离心机振动台试验中常用的叠环式模型箱,进行了单一均匀土和成层土场地在地震作用下的振动模拟计算,对离心机振动台试验中存在的模型箱效应进行了数值模拟,并结合试验结果对叠环式模型箱边界效应的影响进行了分析.数值模拟与试验结果表明,叠环式模型箱较好地模拟了自由场在地震作用下的真实反应,土层的加速度反应峰值、波形以及Fourier幅值谱与精确解误差较小,较好地消除了边界效应对土体地震动反应的影响.

Boundary Effect of Laminar Model Box for Shaking Table Tests on Geotechnical Centrifuge System

Numerical study is carried out for the solution to problems of boundary effect of laminar model box for dynamic centrifuge model test.Seismic responses of single layer soil and layered soil in laminar model box are simulated respectively and the numerical solutions are compared with the exact solutions.Finally boundary effect of laminar model box is analyzed combining with the numerical simulation results and the test results. Both show that the peak accelerations,the shapes of acceleration time history and the Fourier amplitude spectra are in good agreement.The results indicate the laminar model box avoids the disadvantages of the boundary effect and can simulate the real seismic response of free field well.So the paper verifies the validity of the simulation design of soil boundary effect by laminar model box,which provides a basis for dynamic centrifuge model test for soil-underground structure interaction system.