RESEARCH ON INTERNAL EROSION OF SOIL THROUGH DISSOLUTION TEST

Internal erosion of soil by piping has been considered as one of the most common reasons for the failures of hydraulic structures as well as natural slopes. Recent explorations on dissolution test by using the erodible material to simulate the detachment of soil particles have provided valuable insights into the quantitative evaluation of mechanical consequence of internal erosion. In this research, piping effect was successfully achieved by dissolving a preplaced glucose column inside the sandy specimen. Variations on the small strain properties including the Young's modulus and Poisson's ratio were investigated through a series of cyclic loadings with the help of local displacement transducers. Shear strength at the post-erosion state was also obtained. According to the test results, non-uniform local strains occurred along the erosion path. The void ratio of eroded specimen became larger after the dissolution of glucose. Obvious reduction in Young's modulus and increase in Poisson's ratio were observed. Due to the compression and clogging of the eroded voids, no significant degradation in the peak shear strength was found in the eroded specimen compared with the clean sand specimen.