关键词: 沉降, 宏细观试验, 回弹, 回灌, 排水

Abstract: Using a self-designed apparatus for sand sample withdrawing and recharging water, macro vertical deformation of sand sample sand meso move of a sand particle induced by withdrawing and recharging water were analyzed. Vertical deformation of sand samples was measured in the test. Local soil particle pictures were taken and displacements and orientations of the soil particles were investigated with a geotechnical digital image processing (GeoDIP) software. Initially the sand was restructured. The sand settlement arose during withdrawing water and became larger during water recharging as a result of visco-elasto-plastic deformation of the sand sample. After the sand sample became stable, the settlement value became smaller than the initial stage during withdrawing water . The esilience value became larger than the initial stage during recharging water. Rotation of soil particles was small during the first withdrawal, became considerably large in the third withdrawal, and then became negligible during the sixth withdrawal. This work provides a reference for controlling city land subsidence.