In recent years some multi-mode pushover procedures taking into account higher mode effects, have been proposed. The responses of considered modes are combined by the quadratic combination rules, while using the elastic modal combination rules in the inelastic phases is not valid. Here, an optimum weighted mode combination method for nonlinear static analysis is presented. Genetic algorithm is ...

The main objective of this study is to compare the structural members capacity between different types bridges structures under seismic load. results modal analysis showed that models box girder bridge, precast T and U steel bridge had higher values natural frequency comparing with others Pushover in transvers direction bent No. 2 which was located middle superstructure displaced more than 1 3....

Under major load earthquakes, reinforced concrete structures designed according to the current codes will experience an inelastic deformation which is difficult predict and control. Performance-based plastic design (PBPD) methodology applied forward in this study. In method, as performance criteria, target drift yield mechanisms are preselected. Based on work-energy balance principle, base shea...

The widespread brittle failure of welded beam-to-column connections caused by the 1994 Northridge and 1995 Kobe earthquakes highlighted the need for retrofitting measures effective in reducing the strength demand imposed on connections under cyclic loading. Researchers presented the reduced beam section (RBS) as a viable option to create a weak zone away from the connection, aiding the preventi...

the present research is concerned with the determination of ductility, over-strength and response modification factors of coupled steel shear wall frames. three structural models with various numbers of stories, bay width and coupling beam height were analyzed using static pushover and incremental nonlinear dynamic analyses. the ductility, over-strength and response modification factors for the...