基于综合结构势概念的海口原状红黏土K-G模型修正  

MODIFICATION OF KG MODEL BASED ON COMPREHENSIVE STRUCTURE POTENTIAL FOR NATURAL RED SOIL IN HAIKOU

作　　者：吴小锋[1] 李光范[1] 胡伟[1] 杜娟[1] 徐耘野[1] 

机构地区：[1]海南大学土木建筑工程学院,海口570228

出　　处：《工程地质学报》2013年第6期973-980,共8页Journal of Engineering Geology

基　　金：国家科技支撑计划课题(2013BAK05B03);海南省自然科学基金(513144和513139)资助

摘　　要：土的结构性是引起天然土和重塑土各项性质差异的最主要原因。基于考虑土体结构性影响的岩土工程方法和手段应代表岩土工程实践发展方向的这一认识,本文以建立海口原状红黏土的结构性本构模式为研究目标。在结构性定量化指标上,引入综合结构势的概念,建立岩土微结构、胶结作用与宏观力学效应之间的定量表达关系。通过对海口地区所取原状红黏土和相应重塑土进行等向固结排水试验和p=常数的三轴压缩排水试验,分别定义应力型结构性参数和应变型结构性参数。同时发现两者相对于平均主应力存在着归一性化特性,能较好地描述海口原状红黏土的结构性。在此基础上对K-G模型进行了结构性的修正,并进行了数值模拟。结果显示,修正K-G模型能够定量描述海口红黏土的结构性,较好地反映原状红黏土的结构性及预测原状红黏土的应力应变关系。Soil structure is the main reason causing the differences between natural and remolded soils. The soil structure have impacts on methods and means of geoteehnical engineering. This paper establishes a structural consti- tutive model of Haikou red clay. Based on structural quantitative indicators, the concept of comprehensive structure potential is introduced. It builds quantitative expression among geoteehnical microstructure, cementation and macro- scopic mechanical effects. The stress typical structural parameter and strain typical structural parameter are defined. They are obtained through the isotropic consolidation test and p = constant shearing test respectively. Both,~parameters exist the normalized linearization relationship relative to average principal stress. The result can describe the Haikou undisturbed red clay structure. These parameters are used to modify the K-G model. A numerical simulation is car- fled out. Results showed that the modified K-G model can describe the structure of Haikou undisturbed red clay, and well predict the stress-strain relationship of undisturbed red soil.

关 键 词：结构性 综合结构势 K—G模型 

分 类 号：P642.3[天文地球—工程地质学]