Sustainable Operation of Belgrade Landfill—Assessment of the Landfill Liner by Numerical Calculation

The Vinča landfill was established in 1977. For more than 40 years, solid communal waste from Belgrade (Serbia) has been disposed of without any pretreatment or primary waste separation in the bed of the Ošljanski potok (Ošljan stream). Since the landfill was not built to meet requirements valid for sanitary landfills and environmental protection principles, today it represents a significant environmental problem, polluting the Danube River, surrounding agricultural land and air. One of the options considered for landfill remediation allowing sustainable landfill operation in the future consisted of the construction of a separation and sealing layer on the current landfill surface, before continuing with waste disposal. The waste would then be deposited in a controlled manner into the sealed basin. The objectives of the numerical calculations presented in this paper were: (1) to determine the distribution and values of the axial force in the HDPE sealing geomembrane, which is a part of the landfill liner, along its length, (2) to predict the expected vertical deformations at the level of the sealing geomembrane, (3) to predict the expected magnitudes of settlement in the crown of the landfill at the time after the completion of waste placement and at the time of the completion of consolidation of the subsoil. The calculations were performed using an advanced Hardening-Soil constitutive material model for the landfill subsoil and considering a realistic progression of planned waste placement steps. The results of the calculations performed allowed for the identification of potentially problematic sections. Damage to the geomembrane spread over the current waste could occur along these sections, due to excessive deformations leading to overstressing of the geomembrane.