Análise do risco sísmico para estruturas de uso essencial no Brasil

Abstract

Over time, the natural phenomena have resulted on many human, economic and millions of homeless losses. Among these phenomena, the earthquakes are some of the most unpredictable. To reduce these losses, several methodologies for the seismic risk analysis have been developed in which the vulnerability assessment represents a fundamental step. The choice of method to evaluating the structure vulnerability due to a determined seismic action depends mainly of the seismic characteristics of the zone under study. The Brazilian territory is in inter-plates region presenting low seismic activity. The Capacity Spectrum Method (CSM) is best suited to these conditions. This is a quantitative method and is one of the most used in the world. The objective of this work is to evaluate the seismic risk of model structures inserted in seismic regions classified according to the Earthquake Resistant Structures Design Code (NBR 15421:2006). There are four model structures that represent the buildings of essential use, varying the number of floors and the structural configuration in terms of horizontal and vertical irregularities. The results obtained from the risk analysis are presented in graphs that show the global damage index (ID), for each structure and in each zone studied. The obtained IDs show the importance of the structural configuration in these buildings, when reducing the seismic risk is treated.