砂土自由场地震响应的离心机试验研究

离心机模型试验是研究岩土地震工程问题的有效手段。本文使用层状剪切箱,通过干落法制备了均匀的砂土模型,进行了离心机振动试验;观测了振动过程中孔隙水压力的发展,土体的加速度响应、侧向变形以及竖向沉降。结果表明,土体的运动和变形与孔隙水压力的发展密切相关,但离心机中的试验现象和现场观测的现象存在显著区别。研究结果增强了对振动过程中土-水之间相互作用机理的理解,同时为自由场地震响应分析方法的验证提供了基础数据。

Centrifuge modeling of seismic response of free sand ground

Centrifuge model test is an effective approach to study the issues related to geotechnical earthquake engineering.A centrifuge dynamic test was performed on a uniform free saturated sand ground model,which was prepared by the dry deposition method and contained in a laminar shear box.Acceleration,lateral displacement,vertical settlement as well as excess pore pressure were measured during the shaking event.It was observed that the motion and the deformation of soil body are closely associated with the development of excess pore pressure,but there exists remarkable difference between the phenomena occurring at the centrifuge and in the field.The results further our understanding of soil-water interaction under shaking,and provide the data for validating the analytical methods of the seismic response of free ground.