中文摘要：

利用大型拉拔设备,结合数码可视化跟踪技术和土体变形无标点量测技术,进行砂土与土工合成材料拉拔试验,分析不同法向压力、格栅嵌固长度和格栅类型对拉拔特性的影响。以数码可视化跟踪技术跟踪拍摄砂土与土工合成材料界面的相互作用过程,并分析力格栅拉拔过程中砂土接触位移的规律。分析结果表明,在低法向压力下拉拔阻力较快达到峰值,拉拔曲线表现为软化的特性,在高法向压力作用下拉拔阻力需要较大的拉拔位移才能达到峰值状态。长试样格栅需要更大的拉拔位移才能达到拉拔阻力峰值。界面摩擦角和摩擦系数比K随着土工格栅埋入长度的增加而变小。拉拔过程中格栅前端首先受力开始位移,然后格栅中部与后端依次受力带动周围的砂颗粒运动,最后形成连续的拉拔位移界面。

英文摘要：

Using digital video tracking technique,non-target measuring technique and large-scale pull-out equipment,a pull-out test was carried out to study the pull-out characteristics of sand and geosynthetic under different normal pressure,geogrid length and geogrid type.The digital video tracking technique was used to track the interface interaction of sand and geosynthetic and analyze the variation of sand interface displacement during pull-out process.The results showed that under low normal pressure,the pull-out resistance was rapidly maximized,and the pulling curves appeared softening.Under high normal pressure,the pull-out resistance was maximized with a larger pullout displacement.Long sample of geogrid needed greater displacement to maximize the pull-out resistance.Interface friction angle and friction coefficient ratio K decreased with the increase of embedded length of geogrid.In pull-out process,the front-end of geogrid was first subjected to pull-out force and move,and then the middle and back-end of geogrid were in turn driven by the forces and motivate the movement of nearby sand particles,which eventually resulted in a continuous displacement of pull-out interface.