Nonlinear static analysis of reinforced concrete framed buildings - A case study on Cairo earthquake
Abstract
On October 1992, a devastating earthquake struck Cairo causing detrimental effects in reinforced concrete (RC) buildings ranging from repairable damage to total collapse. Considerable attention has been paid in order to explicitly evaluate how RC buildings are likely to perform during earthquakes. This paper presents, through numerical simulations, a nonlinear static analysis to assess the performance of a residential 12-storey RC moment-resisting-frame building located in Cairo. The well-known software package ETABS is used for implementing the framed building model and performing the pushover analysis. The analysis is first performed under the equivalent static force technique as a primary step. In the second and main step of analysis, the nonlinear static pushover analysis is performed following the ATC 40 procedures in assessing the performance of the framed building under two different levels of shakings. The pushover analysis is carried out in both x and y-directions. The results of the study showed that properly designed buildings perform well under seismic load level fits Cairo zone where the building clearly behaves like strong column-weak beam mechanism. However, under unexpected seismic load of peak acceleration exceeds the devoted for Cairo, the building seems to be vulnerable and need to be strengthened where the formed plastic hinges appear in dangerous levels.References
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