膨胀土增湿和干燥过程中的细观结构变化研究  

Study on Meso-structure Changes of Expansive Soils during Wetting-drying Cycles

作　　者：姚志华[1] 陈正汉[1] 

机构地区：[1]后勤工程学院军事建筑工程系,重庆400041

出　　处：《水利与建筑工程学报》2009年第3期1-4,26,共5页Journal of Water Resources and Architectural Engineering

基　　金：国家自然科学基金项目(10672182);后勤工程学院研究生创新基金资助项目(2007)

摘　　要：为了研究水分对膨胀土裂隙演化的影响,对重塑膨胀土进行了无约束条件下的湿干循环试验,并在试验过程中对土样进行CT扫描,跟踪试样裂隙生成以及闭合情况。研究结果表明:无约束条件下增湿和干燥都能引发裂隙的产生的和闭合;在增湿过程中小裂隙会闭合而大裂隙会扩展;在干燥过程中小裂隙会扩展而大裂隙会收缩。基于CT细观数据定义了损伤变量,建立了湿干循环过程中土的损伤演化方程。In order to research the influence of moisture to the evolution of expansive soil＇s crack, the wetting-drying cycle tests for remolded expansive soil are carried out under an unrestricted condition, and the samples are scanned with CT to observe the production and closure of the crack. The research results indicate that both wetting and drying can induce the production and closure of the cracks under the unrestricted condition. During wetting process, small cracks would be closed, but big cracks would be developed. During drying process, small cracks would be extended and big cracks would be contracted. Based on CT mesotest data, the damage variable is defined in this thesis, and a damage evolution equation is proposed during the wetting-drying cycles.

关 键 词：湿干循环 CT扫描 裂隙 损伤演化方程 

分 类 号：TU411.92[建筑科学—岩土工程]