부산대학교 도서관

Internal erosion is one of the important causes of soil damage. In this paper, an erosion-stress coupling apparatus was developed to investigate the mechanical property of soil after internal erosion. Main efforts were devoted to rebuilding pressure cell so that soils can be eroded under confining pressure and deviator pressure. The hydraulic gradient is controlled by using the water-head control method which can provide up to 40 m water-head. The volume change of the sample can also be accurately measured by the volume controller. The eroded particles were collected by the eroded soil collection system. Triaxial consolidation drained shear tests after internal erosion were performed on gap graded soils. It was found that the drainage failure strength and drainage internal friction angle of soil after internal erosion under confining pressure decreased with the increase of fine particle loss. Based on the experimental data, amodified Duncan-Chang model considering fine particle loss was introduced. Numerical modelling of vertical displacement of dam was carried out by using the modified Duncan-Chang model, and it was found that when the fine particle loss exceeds 10%, the displacement increases significantly.