压缩过程中天然沉积土应力灵敏度的变化规律  

Variation reqularity of stress sensitivity of natural clay during compression

作　　者：钱森[1] 史剑[1] 丁建文[1] 

机构地区：[1]东南大学交通学院,南京210096

出　　处：《东南大学学报（自然科学版）》2015年第6期1180-1184,共5页Journal of Southeast University：Natural Science Edition

基　　金：国家自然科学基金资助项目(41372309;51378118);水利部公益性行业科研专项经费资助项目(201401006);江苏省普通高校研究生科研创新计划资助项目(CXLX13_111)

摘　　要：为了描述压缩过程中天然沉积土应力灵敏度随固结压力的变化规律,基于耦合应力灵敏度的概念和Liu-Cater模型的建模思路,将Liu-Cater模型引入应力灵敏度评价体系中,建立了应力灵敏度变化模型.将已有文献中天然沉积土原状样与重塑样的一维压缩试验实测结果与应力灵敏度变化模型预测结果相比较,以验证所提模型的适用性.结果表明:应力灵敏度变化模型预测结果与试验实测结果均具有良好的一致性;应力灵敏度在固结屈服压力时处于最大值,之后随固结压力的增大而逐渐减小至1;应力灵敏度衰减指数的大小主要决定于土的种类及土结构性的特征,软黏土的应力灵敏度衰减指数通常大于硬黏土;土结构性破坏越剧烈,应力灵敏度衰减指数越高.In order to describe the variation reqularity of the stress sensitivity of natural clay with the consolidation stress during compression, a stress sensitivity change model was proposed by introducing the Liu-Cater model into the stress sensitivity framework based on the definition of the stress sensitivity and the modeling idea of the Liu-Cater model. The applicability of the proposed model was verified by comparing the simulation results of the stress sensitivity change model with the onedimensional compression test results of undisturbed and remolded samples of natural clay from the literature. The study results show that the simulation results of the stress sensitivity change model agree well with the test results. The stress sensitivity reaches a maximum value under the consolidation yield stress and gradually decreases to 1 with the further increase of the consolidation stress. The reduction index of the stress sensitivity depends on the soil type and the characteristic of soil structure. The reduction index of the stress sensitivity of soft clay is usually higher than that of stiff clay. The more rapid the destruction of soil structure, the higher the reduction index of the stress sensitivity.

关 键 词：天然沉积土 土结构性 应力灵敏度 一维压缩 

分 类 号：TU411[建筑科学—岩土工程]