单向塑料土工格栅与土界面作用特性的试验研究

土工格栅与土的界面特性直接决定加筋土工程的稳定性,所以格栅与填料的界面技术指标是土工加筋关键的设计指标。本文中,以单向塑料土工格栅为加筋材料,以粘土、砂质粉土、粉细砂、砂砾料为填料,也在大尺寸接触面试验仪上进行拉拔试验;以单向塑料土工格栅为加筋材料,以粘土为填料进行直剪试验。结果表明:粘土与格栅间界面的剪切强度一般很低;砂砾料中的拉拔曲线呈台阶状,摩擦角不是常数;拉拔强度指标和直剪强度指标的适用情况不同。这些可以作为土工格栅加筋工程设计的参考。

Experimental study on the interaction characteristics between single direction plastic geogrid and soil

The interaction characteristics between geogrid and soil directly determine the stability of the geosynthetic reinforcement engineering.Hence,the interaction characteristics are the key design index.In this paper,the pull out tests of plastic geogrid in clay,sandy silt,fine sand and grail are carried out by using the large scale apparatus of interface.The direct shear tests between plastic geogrid and clay are carried out,too.The test results show that the shear strength of interface between clay and geogrid is very small,the pull-out curve of grail is stepped,meanwhile,the angle of internal friction is not constant,the pull out strength index is different from the direct shear strength index in the applicaiton range.These results can be used as reference for engineering design of soil reinforcement.