考虑软土结构强度的次固结特性试验研究  

Experimental study on secondary consolidation considering structural strength of clay

作　　者：雷华阳[1,2,3] 张文振[1] 丁小冬[1] 王学超[1] 陈丽[1] 黄茂松[3] 

机构地区：[1]天津大学土木工程系,天津300072 [2]天津大学滨海土木工程结构与安全教育部重点实验室,天津300072 [3]同济大学岩土及地下工程教育部重点实验室,上海200092

出　　处：《岩土工程学报》2013年第7期1221-1227,共7页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(51078262);国家重点基础研究发展计划(973)项目(2010CB732106);同济大学岩土及地下工程教育部重点实验室开放研究基金项目(KLE-TJGE-B1101)

摘　　要：常规的次固结系数Ca计算方法并没有考虑土体结构性的影响。对原状土和人工结构性土进行了一系列的次固结压缩试验,研究了结构强度q对软土次固结系数Ca的影响。研究表明所提出的先期固结压力pc计算方法有效地降低了Casagrande法的误差;人工结构性土能够很好地反映结构性对土体固结特性的影响;结构性的存在能够减小土体进入次固结阶段所需时间;当荷载接近或超过土体的结构屈服应力σk时,土体残余的结构性有利于次固结变形的发展;软土的次固结系数Ca随着结构强度q的增加呈较好的线性增长关系;所提出的次固结系数Ca计算方法引入了结构强度q,为预测结构性软土的次固结变形提供依据。The conventional methods for the secondary consolidation coefficient of soils do not consider the influence of structure.In this work,the secondary consolidation tests on undisturbed soils and artificially structured soils are carried out to study the influence of the structural strength on the secondary consolidation coefficient.It is shown that the proposed method for preconsolidation pressure can effectively reduce the errors of Casagrande.The artificially structured soil can well simulate the influence of structural characteristic on the consolidation of the clay.The structural characteristics of the soils can make it accelerate into the secondary consolidation stage.The remnant structure of the soils may be conducive to the secondary consolidation when the load is close to the structural yield pressure.At the same time,the secondary consolidation coefficient of the soils has a strong correlation with the structural strength.A method is developed,which is useful for the prediction of the secondary consolidation deformation of structured soils.

关 键 词：软土 结构性 人工结构性土 先期固结压力 结构屈服应力 结构强度 次固结 

分 类 号：TU411[建筑科学—岩土工程]