Influência de precipitação extrema pontual na estabilidade de taludes de aterro industrial

Abstract

The increase in solid waste generation, driven by population growth, planned obsolescence, and the intensification of industrial activities, has amplified the demand for environmentally adequate final disposal systems. In this context, industrial landfills play a fundamental role in the disposal of hazardous waste, requiring rigorous environmental and geotechnical safety conditions. At the same time, the increasing frequency and intensity of extreme climatic events have raised concerns regarding the effects of water infiltration on the stability of these structures. Given this scenario, the objective of this study was to evaluate the influence of the extreme rainfall recorded on the rainiest day of February 2026 on the slope stability of an industrial landfill located in Juiz de Fora, Minas Gerais. To this end, a numerical water flow modeling analysis was performed using the SEEP/W software, followed by stability analyses using SLOPE/W, both part of the GeoStudio 2012 package. The flow modeling was carried out under transient conditions, since it accounts for time variation, and the rainfall event used corresponded to the highest daily precipitation recorded in the municipality in February 2026, equivalent to 138.6 mm in 24 hours. The results indicated that rainwater infiltration promoted a reduction in negative pore-water pressures within the superficial layers of the embankment, evidencing a decrease in matric suction. Pore-pressure variation occurred mainly in the shallower layers of the landfill. As a consequence, the factors of safety showed only slight reductions across the three analyses performed: Analysis 1 decreased from 6.103 to 6.049 (0.88%), Analysis 2 from 2.834 to 2.832 (0.07%), and Analysis 3 from 1.837 to 1.825 (0.65%). Despite these variations, all safety factors remained above the minimum value of 1.50 recommended by ABNT NBR 11682:2009. It is concluded that, for the geometric, geotechnical, and hydraulic conditions adopted in the modeling, the extreme rainfall event negatively affected the stability of the industrial landfill, although it did not compromise its overall stability. These results reinforce the importance of coupled flow-stability analyses in assessing the behavior of landfills subjected to extreme rainfall events, contributing to the improvement of design practices, drainage systems, and geotechnical monitoring strategies.