土工格栅对土的加固机理在于格栅与土的相互作用, 其中, 格栅横肋所起的作用十分重要。借助于室内中型拉拔试验, 分析了单向土工格栅和双向土工格栅横肋的受力特点。试验结果表明:横肋在土工格栅拔出过程中提供超过30%的摩擦阻力;去掉土工格栅的横肋后, 界面摩擦因数和黏聚力都产生了较大幅度的降低;试验过程中所测出来的拉拔力中仍然有一部分是由于格栅横肋作用所产生的力, 最终计算结果要小于格栅横肋实际发挥时的结果。
The interaction between geogrid and soil explains the reinforcement mechanism. Geogrid ribs play a very important role. By middle-scale indoor pull-out test, we analyzed the forces acting on one-way geogrids and two-way geogrid ribs. Results revealed that ribs contributed over 30% of the friction during the pull-out. The friction coefficient and cohesion of interface reduced remarkably in the absence of ribs. Part of the pull-out force measured during the test was provided by geogrid ribs, so the calculation result was smaller than the actual situation.
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