Stability of Stored Municipal Waste for Different Sealing Systems

The paper presents analyses of the municipal waste stability, stored in a landfill with the specific parameters of the waste massif, such as height, width and slope inclination. The massif of waste is lined by a simple drainage/sealing layer, consisting of a sand layer, non-woven geotextile, HDPE double-textured geomembrane and two different sealing mineral layers. The structure stability analysis was performed using a numerical program, relating to the methods: Fellenius/Petterson, Bishop, Spencer, Janbu and Morgenstern-Price. The considerations were carried out according to approach 3 (DA3) for the ultimate limit state GEO of Eurocode 7. The values of the utilization factor and the factor of safety were compared. Municipal waste is generally stable if the slope of the waste is ≤25°. With a slope inclination of 30°, the structures of waste massifs are stable up to a height of 10 m. Using the Fellenius/Petterson method can lead to an underestimation of the factor of safety and an overstatement of the degree of utilization; other methods give comparable results. Changing the material of the mineral sealing layer leads to a change in the course of the circular slip line.