Centrifuge Model Tests On Deformation And Stability Of Landfill Slopes

With China’s rapid economic development and urbanization level, the production of municipal solid waste increases heavily. The landfill deformation and stability issues have become prominent problems. Uneven settlement deformation based on the extension of the old landfill, high water seepage-induced slope instability and son on, a series of issues must be studied and solved.With taking reference to the model soil producing, we selected one model soil, of which the main properties such as bulk density, compressibility, stress-strain relationship, shear strength, permeability and so on are in equivalent of municipal solid waste in China. Centrifuge model tests about landfill expansion were carried out. We research on the deformation caused by landfill expansion. The main points are cared on the settlement and horizontal deformation of the old landfill in the additional loading induced by the new landfill upon it.Meanwhile, we invented a water serving system under conditions of centrifugal acceleration. Then high-water level and seepage induced landfill slope instability related tests are carried out. It revealed the water-induced landfill landslide mechanism and evolution. We analyzed the landslide difference between the landfill and traditional silt. Then we proposed landfill typical failure modes and alert water level threshold, for providing scientific basis for the design and safe operation of the landfill.Hardening constitutive model are used for calibrating parameters of model solid waste. With using Fish language, we embedded FLAC programs to analyze expanded landfill deformation, and compared simulation results with centrifuge model test results. Numerical simulation results and experimental results are in good agreement. It proved the hardening constitutive model calibration is correct. With Geo-slope software platform, we simulated landfill high water level and seepage caused landslide of landfill. It verified the correct of the shear strength corresponds to20%strain for the analysis parameters.