土工格栅的蠕变特性是影响其在永久性加筋土结构中应用的重要因素之一。目前，大多数蠕变试验是在无约束条件下进行的，与格栅在加筋土结构中应用的状态和条件有明显差别。采用HDPE土工格栅进行了一系列在砂土中不同荷载水平下的侧限约束蠕变试验，获得了格栅在砂土中的蠕变发展规律；并与无约束(在空气中)的蠕变试验成果相对比，结果表明，侧限约束可以显著减小格栅的蠕变量。

Creep of geogrid is an important property which affects its application in permanent reinforced structures. At the present time, most of the creep tests are carried out under unconfined conditions which were obviously different from the actual status of geogrid used in geotechnical engineering structures. A series of confined creep tests on HDPE (High Density PolyEthylene) geogrid are carried out in granular soil. The relation between creep deformation and time is obtained under different vertical pressures. The results show that the confined creep strain are smaller than that obtained by common unconfined creep tests. Sand confinement  could remarkably reduce the creep of geogrid.