土工袋层间摩擦特性试验研究

Experimental studies on interface friction characteristics of soilbags

土工袋层间摩擦是土工袋柔性挡土墙设计中应该考虑的关键因素,其大小直接决定了土工袋挡墙的内稳定性。通过铝棒土工袋的摩擦试验说明柔性土工袋层间摩擦与刚性体间摩擦特征的不同,进行了不同袋内材料、土工袋排列方式以及运行环境(水上或水下)等条件下的土工袋层间摩擦试验。结果表明:土工袋层间摩擦力随着袋体沿受力方向变形的增大而逐渐增大,当层间发生整体滑动时达到最大值,并趋于稳定;土工袋层间摩擦不仅与编织袋体的摩擦有关,而且受袋内材料粒径大小及排列方式的影响;土工袋浸泡于水下时,由于水的润滑作用使得编织袋间的摩擦作用减小,袋内材料为细颗粒的土工袋层间摩擦作用减小,而袋内材料为粗颗粒的土工袋层间摩擦变化不大。

The stability of retaining walls constructed with soilbags is closely related to their interlayer friction. The difference of the interlayer friction of flexible soilbags from that of rigid bodies is investigated through the tests on the bags filled with aluminum rods. A series of laboratory tests are conducted to study the influences of the materials filled into bags, the inter-layered arrangements of soilbags and the water on the interlayer friction of soilbags. It is indicated from the experimental results that（1） The frictional force between two flexible soilbags increases with the interlayer displacement of soilbags, and reaches the maximum value at the beginning of the whole slippage between two soilbags and then tends to be stable;（2） The interlayer friction of soilbags is influenced by the bag friction, the grain sizes of filling materials and the interlayer arrangements of soilbags;（3） Owing to the lubricating effect of water on bags, the interlayer friction of the soilbags filled with fine materials decreases when they are placed underwater. However, the interlayer friction of soilbags filled with coarse meterials is slightly influenced by water.