软土地基上的港口陆域回填区场地地震反应分析

Seismic ground response analysis of port backfilling land platform built on soft soil foundation

在软土地基上通过回填砂形成的港口后方陆域,其场地为在密实砂层下卧软弱土层的特殊场地。利用一维场地地震反应分析软件DEEPSOIL的时域非线性分析方法建立分析模型,选择10组地震加速度记录作为输入地震动,分析该类特殊场地的地震反应。结果表明,软弱土层在强震作用下会产生大的剪切变形,使滞回阻尼充分发挥从而耗散地震能量;地震在通过软弱土层向上传递过程中迅速减小,软弱土层具有明显的减震和隔震效果。

For these port backfilling land platforms formed by sands built on soft soil foundation,its ground condition is special,which consists dense sand layer on top and with soft soil layers underneath.An analysis model is established by using the time-domain nonlinear analysis method of one-dimensional seismic ground response analysis software DEEPSOIL,and 10 sets of seismic acceleration records are selected as input ground motion to analyze the seismic response of this special ground.The results show that the soft soil layer will produce large shear strain under the action of strong earthquake,which fully utilizes hysteresis damping and dissipates seismic energy.The seismic ground motion decreases rapidly during the upward transmission in the soft soil layer,which means that the soft soil layer has obvious absorptio and isolation effects to seismic.