【摘要】 进行了液化场地自由场振动台试验,试验采用柔性容器以减小边界影响,采用上覆黏土层的饱和砂土作为模型土。试验中再现了液化场地土的震害现象。得出的主要规律有:随着振次的增加,地基的频率迅速降低,阻尼比迅速增大;砂土对地震动起滤波作用;土体的加速度峰值反应在高度上呈"K"形分布;当最初加速度峰值到达前,砂土层中的孔压比存在负值;震后土中振动孔隙水压力不一定随振动的停止而立即开始消散,在短期内可能继续增长。更多还原

【Abstract】 Shaking table model tests on the free field considering the soil liquefaction are described in this paper.A flexible container is fabricated to minimize the box effect.Saturated sand soil is employed as model soil.In the tests,macro-phenomena of soil liquefaction due to natural earthquake are reproduced well,such as sand boiling,water spouting and soil surface sinking.Some important findings from the present tests are as follows.The natural frequency of soil decreases and the damping ratio of soil increases with the increase of the shaking.The liquefied soil can filter the vibration. The response of the acceleration amplitude is in K shape along the height.The phenomena of the transient minus pore pressure occurred in the test.Pore water pressure does not always dissipate in short time immediately after the excitations,but it may keep on increasing too.更多还原