Optimizing Landfill Capacity: A Numerical Study of the Slope Inclination Variation Impact on Landfill Storage Capacity and Its influence on the Safety Factors under Different Models

As an attempt to enhance landfill capacity and extend its lifespan, this research explores the effect of slope inclination on landfill storage capacity and its implementation on the safety factors using numerical simulations. A geometric approach was used to determine the capacity change with inclination, and a new probabilistic calculation method, which accounts for the heterogeneity of waste layers, was employed to analyze the safety factor for different slope angles. Over 100 conducted calculations for each inclination were used to investigate the effect of slope variation on landfill safety. The results show that increasing inclination leads to a significant increase in landfill capacity. The safety factor results indicate that the conventional method, assuming homogenous waste, classifies 1:3 and 1:2 slopes as safe, while the new suggested method showed that a 2:3 inclination could be considered safe, especially since the calculation is not considering the safety-enhancing effect of daily cover layers. This study highlights the importance of considering the heterogeneity of waste layers in safety factor analysis, and the use of multi-layered nonhomogeneous calculation method, which provides more flexibility in design parameters. This research presents a significant step forward in constructing safe and cost-effective landfills. The use of a new probabilistic calculation method in designing landfills leads to more accurate and reliable results while maintaining safety standards. This research has important implications for the design and management of landfills and can be used as a guide for future studies in this field.