固结过程非饱和黏性土孔隙结构的演化规律及其对水力特性的影响机制

项目名称： 固结过程非饱和黏性土孔隙结构的演化规律及其对水力特性的影响机制

项目编号： No.51209084

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 水利科学与海洋工程学科

项目作者： 陶高梁

作者单位： 湖北工业大学

项目金额： 25万元

中文摘要： 试验测量的方法只能给出特定状态下的土-水特征曲线，而非饱和土本构关系研究需要获得任意变形条件下的土-水特征曲线，因此研究变形对土-水特征曲线的影响具有必要性和迫切性。变形通过影响孔隙结构来影响土-水特征曲线，因此相关研究离不开孔隙结构的研究。 项目以非饱和黏性土为研究对象，通过固结试验制备不同宏观变形及微观(细观）孔隙结构的试样；采用扫描电镜、土壤切片技术、数字图像技术、压汞技术，定量研究不同变形参量试样的孔隙结构；通过压力板仪测定不同变形参量试样的土-水特征曲线，结合试样饱和渗透系数计算非饱和渗透系数。以试验结果为基础，利用分形理论对孔隙结构进行定量化描述；通过计算孔隙率的变化，建立变形与孔隙结构的对应关系式；结合Young-Laplace方程，建立有效模型定量描述孔隙结构对水力特性的影响规律。项目通过孔隙结构建立数学模型定量描述变形对水力特性的影响，促进非饱和土本构关系的研究与发展。

中文关键词： 压缩变形；孔隙分布；土-水特征曲线；饱和/非饱和渗透系数；黏粒含量

英文摘要： The soil water retention curve under a random deformation is needed for study on constitutive relations of unsaturated soil, while experiments can only give the soil water retention curve under a specific condition. Thus, study on deformation's influence on the soil water retention curve is urgent and necessary. Deformation influences the soil water retention curve by way of influencing the pore structures, thus, related research can not be avoided from the research on pore structures. After performing consolidation experiments of unsaturated cohesive soil, the samples of unsaturated cohesive soil with different macroscopic deformation and microcosmic pore structures are prepared. By using the scanning electron microscope, mercury intrusion technique, soil micromorphology technique and numerical image technique, the pore structures of soil samples with different deformation are studied. The soil water retention curve is obtained by using the pressure plate apparatus while the corresponding saturated permeability coefficient is gotten by the variable water level method. Combined with the soil water retention curve and saturated permeability coefficient, the permeability coefficient of unsaturated cohesive soil is predicted. Based on the experiment results, the pore structure is quantitatively described by using

英文关键词： compression deformation；pore-size distribution；soil-water characteristic curve；saturated/unsaturated permeability coefficient；clay content