干湿循环作用下非饱和膨胀土持水和力学特性与其耦合本构模型

项目名称： 干湿循环作用下非饱和膨胀土持水和力学特性与其耦合本构模型

项目编号： No.11272194

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 孙德安

作者单位： 上海大学

项目金额： 82万元

中文摘要： 我国多地存在非饱和膨胀土。对气候变化敏感的膨胀土，经常因干湿循环引起地质或工程灾害。吸水膨胀和脱水收缩是膨胀土的重要特性，也是区别其他非饱和土的重要特征。研究非饱和膨胀土在干湿循环过程中的持水特性和包括湿胀干缩在内的力学特性及其本构模拟是理解和预测膨胀土的各种灾害和提出防止措施的基础。本项目计划在已有研究成果的基础上，以国内典型的膨胀土为试验材料，利用可控制吸力或量测吸力的非饱和土固结仪和非饱和土三轴仪，以及蒸汽平衡法和滤纸法，在干湿循环条件下对膨胀性土进行持水特性和力学特性及其两者耦合性质的试验研究。在申请人等已提出的膨胀性非饱和土的持水-力学性质耦合的弹塑性模型基础上，考虑干湿循环滞回效应和胀缩性，采用边界面理论和建立超固结黏土本构模型所用的手法，建立能够反映干湿循环滞回效应和吸力作用历史效应的持水-力学性质耦合的弹塑性本构模型。本项目可为膨胀土相关的岩土工程问题提供有用的研究成果。

中文关键词： 膨胀土；非饱和土；持水特性；力学特性；干湿循环

英文摘要： Expansive soils exist in many regions of China, and it is sensitive to the climate change. Geological or engineering disaster often ocurrs due to drying and wetting cycles in the area of expansive soils. Volume expansion and contraction due to wetting and drying are important issues of unsaturated expansive soils and also are important characteristics different from other unsaturated soils. To study water-retention behaviour and mechanical behaviour including volume expansion and contraction during drying and wetting process and their constitutive modelling is a fundmental issue for understanting and predicting various kinds of the disaster and proposing the control measure. On the basis of the existing research results of unsaturated expansive soils, a series of experimental study on the water-retention behaviour and mechanical behaviour of expansive soils and their coupling is planned by using the suction-controllable or measurable oedemeter and triaxial testing apparatus for unsaturated soils,the vapour equilibrium method and the filter paper method, and taking one kind of typical expansive soil in China as a testing material. On the basis of the hydromechanical coupled elastoplastic constitutive model proposed by the applictant et al. for predicting the water-retention behaviour and mechanical behaviour of u

英文关键词： Expansive soil；unsaturated soil；soil-water retention behaviour；mechanical behaviour；drying-wetting circle