Thesis (M.Sc.) - Cairo University - Faculty of Engineering - Department of Civil Engineering

Force reduction factor is one of the most important seismic design parameters to consider nonlinear behavior of structures during strong earthquakes. Based on this, all seismic codes allow reducing earthquake loads to match the actual behavior of structures under earthquakes. In the Egyptian Code for Calculation of Loads, base shear is determined using the elastic strength demand divided by strength reduction factor. This factor is used to consider the ability and the efficiency of structure to dissipate seismic energy through inelastic deformation presented in plastic hinges. It consists of three main components representing ductility, over-strength and redundancy of the building. These factors depend mainly on properties of both the structural system of the building and affecting ground motion. This research focuses on the assessment of the ductility reduction factor which is considered the major component of the reduction factor. Steel moment resisting frames (MRFs) and steel concentric braced frames (CBFs) regular and irregular systems are studied for different heights, different ground accelerations, different response spectrum type and different soil type. It is concluded the significant effect of the previously mentioned parameters on the seismic reduction factor that need to be considered in the Egyptian Code of Loads

Issued also as CD