REDISTRIBUTION OF STORY FAILURE SEQUENCE IN STEEL MOMENT FRAMES

The present study considers equivalent load pattern dependence with variation of the frame design and seeks for its optimal pattern using extensive sampling the design space. The developed hyper optimization includes into two phases: a) determination of loading pattern sample and b) sizing design correspondent to each pattern of base shear distribution over height of the frame. The method is thus utilized hybridizing the harmony search, ant colony and branch & bound method. It is then applied to a number of steel moment frames. The results revealed similar new patterns well superior to those in traditional codes considering distribution of drift/displacement response uniformity. In the newly achieved optimal designs seismic collapse starting point is transmitted to the higher stories rather than lower crucial ones as in the traditional code designs

Keywords:

Static Equivalent Lateral Load Pattern , Seismic Design , Hyper Optimization , Harmony Search , Ant Colony Optimization , Branch and Bound Method