Gravitational mass movements in Brazil: causes, consequences, and solutions

Gravitational mass movements are recurring phenomena in Brazil, causing significant environmental impacts as well as human, social, and economic losses. Data on gravitational mass movement occurrences between 1988 and 2022 recorded 959 events in 16 Brazilian states, resulting in a total of 4,146 victims. Extreme rainfall events in recent years, particularly in Santa Catarina, Rio de Janeiro, Bahia, Minas Gerais, Pernambuco, São Paulo, and Rio Grande do Sul, suggest an increase in consequences due to climate change. Considering this scenario, this article analyzes case studies in states such as Pernambuco, Rio de Janeiro, São Paulo, Paraná, and Rio Grande do Sul, addressing causes, impacts, rupture mechanisms, and adopted solutions. Geological-geotechnical investigations, numerical analyses, and continuous monitoring have been crucial in understanding rupture mechanisms and proposing mitigating solutions. The studies identified geological and geomorphological conditions as the main predisposing factors, while inadequate human actions, insufficient investigation in infrastructure projects, and rainwater infiltration were found to be the primary aggravating and triggering factors. Therefore, with the increased frequency of extreme rainfall, it is essential to adopt new approaches that consider the impacts of these events in urban occupation and infrastructure projects, reinforcing preventive and adaptive strategies to reduce future risks.

Keywords:
Gravitational mass movements; Extreme rainfall; Climate change; Slope stability; Geotechnical engineering