摘要
季节性冻土区垃圾填埋场封场复合防渗系统会受到冻融环境的影响。在冻融循环条件下,作为复合防渗系统保护层的宽级配砾石土与GCL(土工合成材料膨润土垫)接触面的抗剪强度性状至关重要。文中采用直剪仪测定了经室内不同冻融循环作用的复合防渗系统的防渗垫GCL与宽级配砾石土(保护层)之间的抗剪强度,分析了二者接触面抗剪强度与冻融循环次数的关系及其变化规律。试验结果表明,宽级配砾质土与GCL接触面的抗剪强度随冻融循环次数的增加而减小;相同冻融温度条件下,GCL质量含水率对接触面的抗剪强度的影响比较显著,接触面的抗剪强度随GCL质量含水率的增大而减小;随着冻融循环次数增加,接触面的粘聚力逐渐下降,内摩擦角有减小趋势,但降幅较小;宽级配砾质土与GCL接触面强度大于粘土与GCL接触面强度。
The composite impervious systems of landfill closure will be affected by the freeze-thaw environment at seasonal frost region. The shear strength characteristics of contact surface between the GCLs（ Geosynthetic Clay Liners） and the wide grading gravel soil that taken as the protective layer of GCLs liner is essential under freeze-thaw cycles. The shear strength of the interaction between the GCLs and the gravel soil of the composite impervious system is determined by using the direct shear apparatus,and the interface shear strength with the variety of freeze-thaw cycles is analyzed. The results show that the interaction shear strength is decrease with the increasing numbers of freeze-thaw cycle; the effect of the quality moisture content of GCL is obviously on the interaction shear strength at same freeze-thaw temperature,and the interaction shear strength decrease with increase of quality moisture content of GCL; with the increase of freeze-thaw cycle numbers,the cohesive force of the contact surface decreases gradually,and the internal friction angle has the decreasing trend but the decline is lightly; the contact surface strength between the wide grading gravel soil and the GCLs is greater than the contact surface strength of the clay and the GCLs.
出处
《工程勘察》
2016年第4期5-10,共6页
Geotechnical Investigation & Surveying
基金
国家自然科学基金(编号:41062004)
