Overstrength of RC Medium Length Span Bridges

Abstract

Overstrength factors in bridges reported in various studies show great diversity that depends on the type of bridges selected and the set of seismic records used in the analyses. Particularly in Mexico, there are no previous studies that evaluate the bridges’ overstrength. This study determines overstrength factors in medium-length reinforced concrete bridges based on dynamic nonlinear analyses to establish design parameters in bridge regulations in Mexico. More than 3000 nonlinear time history analyses were carried out using 48 bridge models subjected to seismic records from an interplate seismic source. Based on the results, the overstrength factors of simply supported bridges with spans of 30 m and 50 m and substructures composed of one or more reinforced concrete columns were determined.