Mapeamento estrutural e análise de estabilidade de taludes de um corte de estrada no município de Boa Viagem - CE

Abstract

In rock mass stability studies, it is of fundamental importance to know the geological structures present in the rock mass, because they will dominate the stability or instability conditions of the rock slope. With a good geological-geotechnical mapping of the rock mass it is possible to evaluate the geological risk level using computational tools. These softwares aligned with a good mathematical model of rupture that best fits the study environment are the best ways to assess the risk of slope rupture and propose possible solutions to ensure rock mass stability. Thus, this paper aims to perform the structural mapping of three sections defined in two road section slopes and to analyze the stability condition using computational tools based on field data obtained from these sections. The methodology was divided into four stages for a better organization of the study, with each stage complementary and dependent on the previous one. The first step was the geological-geotechnical mapping of the three sections, then the second step aimed to perform the kinematic-probabilistic analysis according to the orientation of the discontinuities present in the three sections, with the identification of critical discontinuities for a given type of rupture, the third step was directed to the deterministic analysis, aiming to obtain the safety factor, finally, the fourth step led to the sensitivity analysis, intending to evaluate the variability of geometric and geomechanical parameters obtained in the study. From the results obtained in the kinematic-probabilistic analyses, it was detected conditions for planar rupture only in section TS1 and conditions for wedge rupture and direct and oblique block tumbling in all sections, with very variable rupture probabilities, as for the deterministic analyses of the critical discontinuities, The results of the deterministic analyses of the critical discontinuities showed safety factors greater than one, thus ensuring stability, but when evaluating the influence of the percentage of water saturation in the sensitivity analyses, it was possible to attest a great influence on the reduction of shear strength with increasing slope saturation. Finally, it can be concluded that performing combined analyses between software, as was the case in this study, leads to a better interpretation of the slope's critical state.