干化过程中土-膨润土土工力学特性变化  

GEOMECHANICAL PROPERTY CHANGES OF SOIL-BENTONITES DURING THE DRYING PROCESS

作　　者：周家鑫 闫子壮 汪正楷 李育超[1,2] ZHOU Jiaxin;Yan Zizhuang;WANG Zhengkai;LI Yuchao(Celechnial Research Istiute Zhejiang Universiy,Hanghou 310058.China;Center for Hypergravity Experimental and Inter-disipliary Research,Zhejiang Univesity,Hangzhou 310058,Chine;The Architetural Design and Research Intiute of Zhejiang University Co.,Ld,Hangzhou 310028.China)

机构地区：[1]浙江大学岩土工程研究所,杭州310058 [2]浙江大学超重力研究中心,杭州310058 [3]浙江大学建筑设计研究院有限公司,杭州310028

出　　处：《低温建筑技术》2022年第6期53-57,共5页Low Temperature Architecture Technology

摘　　要：用于地下污染风险管控的土-膨润土垂直阻隔墙会经历干湿循环而服役性能劣化。文中测得了母土为细砂和粉土的两种土-膨润土干化过程中剪切波速与无侧限抗压强度的变化,分析了含水量、母土种类及制样固结压力对上述两个土工特性参数的影响,结合扫描电镜图像分析了其变化机理。研究发现随含水量降低,土-膨润土的两个参数显著增大,破坏变形显著减小;母土种类有一定影响;制样固结压力的影响较小;膨润土胶结作用与基质吸力是引起变化的主要原因。Subjected to the drying-wetting cycles, the performance of soil-bentonite cutoffs walls used for underground pollution risk control deteriorates. The shear wave velocity and unconfined compressive strength of soil-bentonite with fine sand and silt as the base soil under drying were respectively measured. The effects of water content,base soil type, and consolidation pressure during sampling on the two geotechnical property parameters are analyzed,and the mechanism is illustrated with scanning electron microscope(SEM). It is found that the two parameters of soil-bentonites increase significantly with the decrease of water content, and the failure deformation is significantly reduced;the type of base soil has a certain effect;the sample preparation consolidation pressure has a slight effect on the shear wave velocity and unconfined compressive strength of soil-bentonites;the cementation of bentonite and matric suction are the main reasons for the above changes.

关 键 词：土-膨润土 垂直阻隔墙 干化 剪切波速 小应变剪切模量 无侧限抗压强度 

分 类 号：TU443[建筑科学—岩土工程]