Rockfall Hazard Assessment and Geological-Geotechnical Characterization of a Rock Slope in Br-356

Abstract

The rockfall hazard assessment for roads is very important in geotechnical engineering business. As the process is very fast and complex, a hazard analysis is of fundamental importance for the adoption of preventive action plans and mitigation of potential impacts. Therefore, this article presents a hazard analysis for rockfall and the geological-geotechnical characterization of a rock slope on the BR-356, Ouro Preto, Minas Gerais, Brazil. In the methodology, parameters related to the geotechnical characterization, geometry and slope characteristics were inserted, as signs of block fall activity, impact of external influences and characteristics of the catchment area. According to Rock Mass Rating (RMR), the rock slope was classified as Very Good (Class I). The hazard classification for the slope analyzed varies from low to high. When the rainfall of the rainy season is considered, the slope is classified as a high hazard, while in the dry season, it is classified as low hazard. The study revealed that even if the hazard class is low, the slope deserves attention, since there is not enough space for rock blocks to be deposited before reaching the road, which can generate damages and temporarily paralyze the activities of the road.