Earthquake source effect and impact of the applied methodology to assess the overstrength factors of RC bridges

Seismic hazard assessment in several sites worldwide depends on two or more seismic sources. Many countries affected by subduction zones have strong motions earthquakes originated at least important In Mexico, interplate (subduction process) epicenters located the Pacific coast with hypocenter depths less than 45 km and intraplate (intermediate-depth earthquakes) normally inside continent depth hypocenters greater km. Both sources can potentially produce events magnitudes M w 8.0 and, therefore, generate severe damage to country's infrastructure. The design process of bridges Mexico is based chapter Design Manual Civil Structures Federal Electricity Commission. standard allows reduce spectral ordinates spectra ductility overstrength. It establishes an overstrength factor 1.5 spectra, value not well supported Manual. This study evaluates effect source methodology used compute factors common typologies reinforced concrete bridges. capacity was calculated nonlinear static analysis time history analysis. results showed that importance location general terms, overestimates • Influence RC Bridges. Effect dynamic analyses region