Análise do estado de tensão na característica de sismos induzidos por reservatório para um estudo de caso da UHE de Irapé em Minas Gerais

Analysis of the state of stress in the characteristic of reservoir-induced earthquakes for a case study of the Irapé HPP in Minas Gerais

Abstract

The understanding of the seismic evaluation behavior in structures, in general, is extremely important. For regions with low-intensity earthquakes such as Brazil, this assessment is not as widespread, however, there are risks related to earthquakes caused by the filling of the reservoir, little addressed by designers, which are triggered close to the dam and can cause possible damage to the structure. The Irapé Hydroelectric Power Plant (HPP) is the highest dam in the country, at 208 meters. This dam was monitored by the Seismological Observatory of the University of Brasília (OBSIS-UnB) during the filling of the reservoir in 2006. This work aims to evaluate the influence of the reservoir filling of the Irapé HPP and its correlation with the seismic data captured during this filling process. For this, the region of influence of the additional effort along the local crust was evaluated by means of the finite element method via ANSYS software. The results presented found that the events that occurred during the filling of the dam are within the limits of variation of the state of tension, being characterized as events induced by the reservoir being predominantly shallow, being in a region of influence at distances smaller than 4 km from the surface.