Int. J. Structural Engineering, Vol. 6, No. 2, 2015 109 Copyright © 2015 Inderscience Enterprises Ltd. Effect of energy dissipating devices on storey drift and displacement by nonlinear time history analysis H.R. MagarPatil* and R.S. Jangid Department of Civil Engineering, IIT Bombay, Powai, Mumbai – 400 076, India Email: hrm@civil.iitb.ac.in Email: rsjangid@civil.iitb.ac.in *Corresponding author Abstract: The seismic vulnerability of steel moment resisting frame with passive dampers is assessed with 13 different seismic resisting systems. The structural frames are analysed and designed for the loading conditions in Pune. The stiffness effect on the stories is demonstrated through the lateral displacement profile of the building. Hybrid passive dampers with buckling restrained brace of mild steel and aluminium are used to improve lateral stiffness of the structure. Mild steel braces have increased lateral strength and proved to be good energy dissipating devices. The aluminium sections are chosen as energy dissipating device due to its low yield strength. Aluminium buckling restrained braces has improved performance of the structure in the form of reduced storey drift and displacement as compared to basic steel moment resisting frame. By the use of these devices either alone or in combination with BRB, the performance of SMRF has been improved significantly. Keywords: hybrid passive dampers; steel moment resisting frame; SMRF; buckling restrained brace; energy dissipation; seismic vulnerability assessment. Reference to this paper should be made as follows: MagarPatil, H.R. and Jangid, R.S. (2015) ‘Effect of energy dissipating devices on storey drift and displacement by nonlinear time history analysis’, Int. J. Structural Engineering, Vol. 6, No. 2, pp.109–122. Biographical notes: H.R. MagarPatil is a Doctoral Scholar in the Civil Engineering Department at the Indian Institute of Technology, Powai, Bombay, India. R.S. Jangid is a Professor in the Civil Engineering Department at the Indian Institute of Technology, Powai, Bombay, India. 1 Introduction Steel moment resisting frame (SMRF) with open first storey (soft storey) is known to perform well compared with the RCC frames during strong earthquake shaking (MagarPatil and Jangid, 2012). RCC framed structures are more durable and have less