Influência dos plásticos na estabilidade de taludes em aterros sanitários.

Abstract

Landfill plastics are fibrous elements and have a reinforcing effect on shear and tensile strength, characterizing the fiber effect and representing a reinforcement matrix. In order to understand the strength of Municipal Solid Waste (MSW) in landfills, the reinforcing effect of the fibrous materials constituting the waste should be taken into account, as shear strength in landfills is caused not only by friction between grains but mainly by the similar effect to reinforcing fiber and sheet materials, which are the components of the fibrous matrix. The objective of this research determine the influence of plastics on the stability of landfill slopes. This research was developed in three stages, a field stage, where the topographic survey of the landfill cell was performed along with the monitoring of the liquid levels and Municipal Solid Waste (MSW) collection to determine the physical and mechanical properties of the waste. The second step corresponded to the performance of direct shear tests in laboratory on waste samples with different plastics percentages (0%, 7.5%, 15%) to assess the strength parameters, and next, the slope stability analysis of the landfill's cell. The results of the demonstrated characterization that 71% of MSW do not have ASCG, adding to the mixed material, 13.2% selected in the plastics category.In terms of volumetric composition, the percentage of plastics increased to 32.7% of the total analyzed. As for monitoring the levels of use of the four monitored piezometers, two levels higher than the norm and within the ideal range for drainage systems. The shear strength results indicated that with the increase of the plastic percentage, the cohesion increased, but the friction angle decreased to the 15% plastic percentage. In the slope stability analyzes, it was found that as plastic percentages increased the safety factor also increased within predetermined limits.