Experimental Study on the Deformation of a Cut-Off Wall in a Landfill

To effectively solve the leakage problem of landfill leachate, it is necessary to establish a vertical cut-off wall around the landfill site for seepage control. To accurately analyze the deformation of the cut-off wall, a 1/8-scale landfill cut-off wall miniature model is designed and fabricated. The actual force of the cut-off wall is simulated by filling sand on the outer side of the model wall. Meanwhile, a nonlinear finite element model of the wall is established using the ANSYS to simulate the deformation of the seepage wall. The results show that the cut-off wall made from a polyvinyl alcohol-bentonite-fly ash-cement (PBFC) anti-seepage slurry has a high ultimate bearing capacity, and its ultimate strain is approximately 5%, which is much higher than the limit strain of the actual force conditions of the cut-off wall. The horizontal displacement of the cut-off wall is approximately linear and decreases gradually from the top to the bottom, and no reverse displacement is observed. The main stress of the wall is smaller than that of the slurry, and there is no tensile stress. The simulated results are similar to the measured values of the cut-off wall, which indicates the accuracy of the simulation analysis.