土工格栅与粗粒土界面特性的大型直剪试验研究  

Large direct shear test research of interface interaction characteristics of geogrid and coarse grained soil

作　　者：王家全[1] 武标[1] 邹红[1] 周奇[1] 柯刚[1] 

机构地区：[1]广西科技大学土木建筑工程学院,广西柳州545006

出　　处：《广西科技大学学报》2015年第3期78-83,共6页Journal of Guangxi University of Science and Technology

基　　金：国家自然科学基金项目(51469005;51009030);广西自然科学基金项目(2011GXNSFB018003);广西自治区大学生创新创业训练计划项目(201410594043)资助

摘　　要：为分析粗粒土与土工格栅复杂界面作用特性,通过设计改良后的可视化大型直剪设备,采用双向土工格栅为加筋材料,对素粗粒土和加筋粗粒土直剪试验进行界面研究.分别考虑法向压力、粗粒土中的粗粒含量P5等多因素的变化对筋土界面的性质影响.利用高清数码相机对试验剪切过程进行跟踪采集,研究素粗粒土和加筋粗粒土直剪试验过程中剪切面位移场变化规律.结果表明:加筋粗粒土比素粗粒土的内聚力有所增加,内摩擦角有所降低,加筋粗粒土直剪界面区域土体颗粒位移最大值小于素粗粒土的位移最大值,但加筋土界面厚度大于素粗粒土界面厚度.土工格栅对土颗粒的嵌锁作用限制了土颗粒的剪切移动,增强了土体的稳定性,从而提高了土体的抗剪强度.Aimed at analyzing the complex interface the large visual direct shear equipment of improved geogrid, the direct shear test of coarse grained soil action characteristics of geogrid and coarse grained soil, using design and adopting a reinforcement material of bidirectional and reinforced coarse grained soil is conducted to study the interface action mechanism. The influences of the change of the normal pressure and the coarse material content of the coarse grained soil P5 on interfacial properties of reinforced soil are respectively considered. The process of the direct shear test of coarse grained soil and reinforced coarse grained soil is captured images with using the high- definition digital camera. The results show that the reinforced coarse grained soil cohesion is increased and friction angle is reduced than coarse grained soils; Soil particle maximum displacement value of reinforcement coarse grained soil is less than the maximum displacement value of the coarse grained soil in direct shear interface region, but the thickness of reinforced soil interface is greater than that of coarse grained soil interface. Geogrid to the soil particle interlock limits the movement of soil particles, and enhances the stability of the soil, so as to improve the shear strength of the soil.

关 键 词：粗粒土 筋土界面 土工格栅 位移场 

分 类 号：TU47[建筑科学—结构工程]