Seismic performance and cost comparison of concentrically braced frames designed by performance-based plastic design and force-based design method

Abstract

Comparative study of 5, 10 and 15 storied steel Concentrically Braced Frames (CBF) designed by Performance Based Plastic Design (PBPD) method and Force Based Design (FBD) method is presented here. The parameters selected for comparison of the frames are (a) Lateral load distribution (b) Design sections of members (c) Seismic performance and (d) Cost. It is observed that the lateral load’s distribution in case of PBPD frames is found more factual. The column sections of PBPD frames are heavier, and brace sections are lighter compared to FBD frames given the fact that PBPD is designed for higher ductility factor. The PBPD method gives a better seismic performance by achieving the predetermined failure mechanism and avoiding total collapse. Taller structures offer cost-effectiveness for PBPD method.