Seismic energy-based design of BRB frames using multi-objective vibrating particles system optimization

In this paper, a multi-objective optimization method for buckling restrained brace frames is presented accompanied with the nonlinear time-history analysis. A new application of multi-objective and multi-level vibrating particles system for optimizing costs and damages caused by the earthquakes for steel frames is presented. This new meta-heuristic algorithm improves the performance and computational efforts compared to other evolutionary methods. Minimum structural weight and minimum seismic energy (controlled by energy absorption) are identified as two design objectives for three selected mid to high rise structures. Main design constraints include: inter-story drifts, plastic bending rotation of beam-column members and axial plastic deformation of buckling restrained braces.