Deterministic and probabilistic 3D analysis of slope rupture at BR 116 PR/SP highway in unsaturated soil

Abstract

This research was developed with the purpose of presenting a deterministic and probabilistic assessment of the stability of slope located in state of São Paulo-Brazil, in the area denominated Serra Pelada, BR 116 PR/SP, with the incorporation of different suction scenarios in the unsaturated soil. The methodology was composed by 2D and 3D modelling of the slope, in the SoilVision’s SVSlope software, with the imposition of two water levels on the slope, one of 6.5 meters deep and another of 7.5 meters. The results demonstrate the variability of the probability of rupture, the safety factor, and the quantification of mobilized mass volume, in the six suction scenarios. As a result, it is possible to conclude with the analysis that the greater the surface suction in the unsaturated soil, the greater the safety factors of the slope and the lower the probability of rupture. It is also prudent to add that the incorporation of the variability of the geotechnical parameters in the probability analysis of stability, together with the 3D modelling of the slope, allow a more reliable analysis, presenting results of greater applicability in subsequent analyses. Finally, in conclusion, the studied slope is safe regarding its global stability for rupture.