Settlement calculation of landfills under layerwise summation and case study

The placement and settlement processes of a landfill under layerwise summation are simulated by means of the Sowers model, Marques model and stress degradation model. The relevant computer software for predicting the settlement and capacity of the landfill is developed based on the calculation method. The parameters for the above three models are fitted based on part of the measured data in Shanghai Laogang Landfill. A comparison indicates that it is simple to fit parameters but the results are rough by using the Sowers model. The results by means of the Marques model and stress degradation model are similar, but the parameters for the stress degradation model are relatively less and easier to be identified than those for the marques model. The post-construction settlement of Laogang Landfill is calculated by using the stress degradation model and compared to the measured data. It is shown that this model and calculation method can be employed to simulate the placement and settlement processes of Landfills well. The maximum settlement and differential settlement likely occur in the internal part instead of on the surface. Therefore settlements should be calculated before the design of internal structures.