干湿循环作用下非饱和压实黄土变形和电阻率特征的室内试验  

Laboratory Tests on Deformation and Resistivity Characteristics of Unsaturated Compacted Loess Under Dry-wet Cycles

作　　者：秦鹏举 轩龙龙 王建美 邢鲜丽[4] QIN Pengju;XUAN Longlong;WANG Jianmei;XING Xianli(College of Civil Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Shanxi Transportation Technology Research and Development Co.,Ltd.,Taiyuan 030032,China;Shanxi Key Laboratory of Civil Engineering Disaster Prevention and Control,Taiyuan University of Technology,Taiyuan 030024,China;College of Mining Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学土木工程学院,太原030024 [2]山西省交通科技研发有限公司,太原030032 [3]太原理工大学土木工程防灾与控制山西省重点实验室,太原030024 [4]太原理工大学矿业工程学院,太原030024

出　　处：《同济大学学报(自然科学版)》2025年第4期565-573,共9页Journal of Tongji University:Natural Science

基　　金：国家自然科学基金(42177138,41907239);中国博士后科学基金(2020M680909)。

摘　　要：开展了干湿循环作用下非饱和压实黄土变形和电阻率特征的室内试验。首先,获取经历5次干湿循环过程的试样体积变形和电阻率特征以及干燥后表面裂隙;其次,采用恒应变速率法研究不同含水率试样的压缩性质,同时获取电阻率特征;最后,开展了核磁共振和扫描电镜测试以探究试样微观特征。结果表明,随着干湿循环次数的增加,试样膨胀应变和裂隙比增大,而电阻率减小,并均趋于稳定;3次干湿循环后试样的屈服应力明显减小,弹、塑性压缩指数增大;随着干湿循环次数的增加,土体内部小孔隙数量明显增加,中、大孔隙数量变化不明显。Laboratory tests on the deformation and resistivity characteristics of unsaturated compacted loess under dry-wet cycles were carried out.First,the volume deformation and resistivity characteristics during cycling,as well as surface cracks after the desiccation of the sample undergoing five dry-wet cycles were obtained.Then,compression properties of the sample with different water contents were studied by the constant rate of strain(CRS)method,and the resistivity was also obtained.Finally,the nuclear magnetic resonance imaging and scanning electron microscopy were used to study the microscopic characteristics of the sample.The results show that with the increase of the number of dry-wet cycles,the swelling stain and crack ratio of the sample increase and the resistivity decreases,all of them tend to be stable as well.The yield stress significantly decreases and the elastic and plastic compression indexes increase after three wet-dry cycles.With the increase of the number of dry-wet cycles,the number of small pores in the compacted unsaturated loess obviously increases and the number of medium and large pores has a slight variation.

关 键 词：非饱和压实黄土 干湿循环 电阻率 含水率 微观特征 

分 类 号：TU411.3[建筑科学—岩土工程]