上海砂土蠕变变形特征的试验研究  

Experimental research on creep of Shanghai sands

作　　者：张云[1] 薛禹群[1] 吴吉春[1] 刘运涛[1] 蒲晓芳[1] 

机构地区：[1]南京大学地球科学与工程学院,南京210093

出　　处：《岩土力学》2009年第5期1226-1230,1236,共6页Rock and Soil Mechanics

基　　金：国家自然科学基金重点项目(No.40335045);国家自然科学基金项目(No.40772168)资助

摘　　要：采用室内单向压缩试验研究了上海砂土的蠕变变形规律和蠕变机制以及蠕变变形与应力历史的关系。试验结果表明,上海砂土具有明显的非线性蠕变特征,应变与应力、时间的关系可以用幂函数拟合;应力历史对砂土的蠕变性有显著影响,当荷载小于预压荷载时砂土的蠕变性显著减小。上海砂土的蠕变原因主要是砂土颗粒间的相互错动滑移所致。The mechanism and features of creep of Shanghai sands are researched through oedometer tests. The effects of stress histories on creep deformation are also investigated. The experimental results show that the Shanghai sands exhibit nonlinear creep obviously; and the relationship of stress-strain-time can be expressed by power functions. The stress histories have significant effects on the creep of sands. When the load is less than the preloading, the creep of sands is unremarkable. The main reason for creep of Shanghai sands is that the sand grains slide along one another.

关 键 词：砂土 蠕变变形 蠕变机制 应力历史 

分 类 号：TU411[建筑科学—岩土工程]