环境因素对土工格栅蠕变特性的影响

Study of influence of environmental factors on geogrid creep property

针对高密度聚乙烯单向拉伸土工格栅进行了一系列不同环境因素条件下的蠕变试验,研究了应力水平、温度、化学作用、施工损伤以及砂土侧限约束等对格栅蠕变性能的影响。结果表明,温度或应力水平越高,格栅蠕变量越大,蠕变速率也越快;常规条件下单向拉伸土工格栅的蠕变临界应力水平不宜大于40%;化学作用可导致格栅蠕变量增大约10%,施工损伤对蠕变的影响非常显著;另一方面,砂土侧限约束下的蠕变特性与格栅的受力状态有关,填料约束以及上覆荷载作用可大幅降低格栅的蠕变量。

A series of creep tests of high-density polyethylene uniaxial geogrids are performed under different environmental conditions,including the stress level,temperature,chemical reaction,installation damage and confined constraint in sand.The results show that： with the higher temperature or stress level,the creep of geogrid is bigger and the creep rate is faster;the creep critical stress level of uniaxial geogrid is unsuitable to exceed 40% under common conditions;chemical reaction can lead the creep deformation to increase about 10%;the influence of installation damage is obvious;the creep property under confined constraint in sand is related with the stress state of geogrid;the filling material and loading can reduce the creep deformation of geogrid greatly.