摘要
拉拔、直剪、单剪试验常用于材料间界面特性研究,通过对垃圾填埋场中组成复合衬垫的土工膜、土工布和砂土、黏土界面分别进行了土工膜与砂土、土工膜与黏土、土工布与砂土、土工布与黏土的拉拔试验,土工布与砂土、土工膜与黏土的直剪试验及土工网–土工膜–黏土组合界面的单剪试验。研究结果表明:土工合成材料与土界面特性主要取决于土工合成材料的表面性质,直剪和单剪试验得到应力–位移曲线的初始斜率高于拉拔试验;法向应力由低向高变化时控制滑动面也发生了变化,界面特性受到防渗结构层中相邻材料的影响;在3种试验中拉拔试验得到的界面强度包线最高,单剪次之,直剪最低;单剪试验能较合理地模拟垃圾填埋场复合防渗结构的工作条件,建议利用单剪试验技术确定界面的强度参数,直剪试验也是可选择的试验方法。
The pull-out tests,direct shear tests and simple shear tests are often used to investigate the interface behaviors of landfill liner systems.Pull-out tests for the interfaces of geomembrane-sand,geomembrane-clay,geotextile-sand and geotextile-clay,direct shear tests for the interfaces of geotextile-sand and geomembrane-clay,and simple shear tests for the composite liner interfaces of geonet-geomembrane-clay are presented.The test results show that the interface behaviors of geosynthetics and soil mainly depend on the surface characteristics of geosynthetics.The initial slope of stress-displacement curve from the direct tests and simple shear tests is steeper than that from the pull-out tests.The results from the simple shear tests show that the critical interface with the largest displacement in the composite liner is not fixed at a single interface.It can shift from one to another with changing normal stress.The strength envelop is the steepest for the pull-out tests,middle for the simple shear tests,and the lowest for the direct shear tests.The condition of composite liner in landfills can be reasonably simulated by the simple shear tests.The simple shear tests are suggested to investigate the interface strength of liner systems in landfills.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2010年第5期688-692,共5页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学基金项目(50879022)
江苏省自然科学基金项目(20082890)
江苏省六大人才高峰计划资助(2006276)
关键词
拉拔试验
直剪试验
单剪试验
界面特性
pull-out test
direct shear test
simple shear test
interface behavior
