水平地基液化后大变形对桩基础的影响  

Effect of Large Horizontal Post-liquefaction Deformation of Level Ground on Pile Foundation

作　　者：张建民[1] 

机构地区：[1]清华大学土木水利学院,北京100084

出　　处：《建筑结构学报》2001年第5期75-78,共4页Journal of Building Structures

基　　金：国家自然科学基金项目(59979012)资助。

摘　　要：通过对震害调查结果的分析，表明（１）震动液化能够引起水平地基产生较大的侧向变形；（２）可液化水平地基中桩的水平位移的大小和方向，主要受已液化土层侧向变形的大小和方向控制；（３）可液化水平地基的侧向变形，可分为液化前较小的震动变形。液化后震动引起的大中变形以及地震后的永久侧向变形三种情形。可液化水平地基中桩基础的设计，应该考虑这三种不同工作状态下的抗震要求；（４）上部结构－桩－地基的相互作用和响应会因上述三种情况而异，有必要发展新的能够考虑可液化地基侧向变形影响的动力分析方法。Case studies made in this paper show that large horizontal residual post-liquefaction deformation occurred in level ground of saturated sandy soils during the past strong earthquakes, such as the 1964 Niigata earthquake and the 1995 Hogoken-Nambu earthquake in Japan. Liquefaction-induced ground deformation has caused severe damage to pile foundations in liquefied sandy deposits with level surface. It has been found that the ground deformation induced by seismic liquefaction can be divided into three types:(1) smaller pre-liquefaction deformation in shaking,(2) larger post-liquefaction deformation in shaking and(3) residual post-earthquake deformation. All three types of ground defor-mation should be properly considered in aseismic design of a pile foundation in liquefiable level ground.

关 键 词：水平地基 震动液化 侧向变形 桩基础 

分 类 号：TU435[建筑科学—岩土工程]