饱和砂土透镜体液化对建筑物地震反应的影响

采用一种能分析有结构物存在的场地地震液化问题的二维有效应力有限元分析方法，研究饱和砂土透镜体液化对建筑物地震反应的影响。计算中采用了更为合理的迭代方式处理土的非线性，考虑了Ｋｃ对孔压的作用，引入了透射边界。取建筑物为短周期结构。考虑了透镜化宽度、厚度、埋深以及输入地震动类型幅值对结构加速度反应的影响。计算结果表明：（１）所采用的方法与已有的模型实验结果有很好的对应关系，可用于招考莪存在下的场地砂土

Effect of liquefaction of lenticular saturated sand zone on seismic response of buildings

Using 2-D effective stress method the effect of liquefaction of the lenticular sand zone on the earthquake response of building is investigated. The effect of the input form of the seismic ground motion and the thickness, width and depth of the sand lentic1e on the building response is discussed. The results indicate: (1)The results by the method presented in the paper is agreeable with those by the model test. It means that 'the method can be used to analyze the problem of sand liquefaction in the case of existing building.(2)The liquefied lenticle mainly has the effect of isolation on the building with short period and the effect of the vibration isolation increases with the increasing of the thickness, depth and width of the sand lenticle. (3)When subjected to the seismic ground motion of the shock type, the shallow, thin and narrow liquefied lenticle may amplify the response of the building with short:period.