Seismic Response Modification Factor for Special Concrete Structures

Abstract

A comprehensive research work has been performed concerning evaluation of seismic performance of special (mixed) structures such as elevated metro stations with different configurations. Detailed geometrical and material analyses have been carried out through static and dynamic pushover analysis through the present thesis. The work done includes the following topics: - Determine response modification factor R for this type of special (mixed) structure and compare it with both international buildings as well as bridges codes. - Illustrate the effect of seismic code details (sufficient and limited ductility) on the seismic performance capacity on such types of structures. - Evaluate of the stiffness effect of pier column (cantilever or frame) on the response modification factor. -Introduce rational values of the response reduction factor for the analyses such sorts of special RC structures - Investigate the spread of plastic hinge length in pier column and compare it through calibrated empirical relationships in codes and published work in this point. - Study the effect of increasing the initial axial stresses in pier column (post tensioning forces) to improve the seismic capacity of such structures and their effect on the amount of plastic hinge elongation.