关键词: 土工格栅, 膨胀土, 含水率, 界面特性, 拉拔试验, 相互作用, 南水北调工程

Abstract:

The mechanical characters of expansive soil structure reinforced with geogrids are directly affected by the water content, whereas the mechanism is rarely studied before. So, the filling with dimension of 600 mm×600 mm×600 mm laminated shear test apparatus is adopted to carry out a series of pull-out tests to investigate the effect of water content on pull-out behavior of the interface between geogrid and compacted expansive soil. The results show that the water content has a notable effect on the pull-out force and geogrid’s displacement, the characteristics of the interface stress and strain, and the strength parameters of the interface. When the water content is higher, the rigid motion of geogrid occurs earlier, and the pull-out force per width when rigid motion more approaches the peak value; and relation of friction and relative displacement of the interface tends to be more ideal rigid-plastic. The interface quasi-cohesion increases with decrease of water content, whereas water content has little effect on the quasi-friction angle of the interface.

Key words: geogrid, expansive soils, water content, interface behavior, pull-out test, interaction, South-to-North Water Transfer Project