A simple hypoplastic model for simulating the mechanical behaviour of MBT waste

This paper deals with the experimental investigation and numerical simulation of the mechanical behaviour of samples from a "Mechanical Biological Treatment" waste deposit (MBT waste deposit). Laboratory tests with samples of different moisture contents were conducted to determine the basic geotechnical characteristics as well as the stressstrain relations under loading and reloading in a large oedometer with a sample diameter of 50 cm. With respect to a moisture dependent solid hardness, the mechanical behaviour can be well predicted using a hypoplastic constitutive model. As only limited experimental results were available, a simplified hypoplastic model was used. For the calibration of this model it was sufficient to conduct oedometer tests and to use a simple procedure to estimate the angle of friction. The model proved to be satisfactory for modelling the compaction behaviour of MBT waste observed in experiments.