Energy absorption capacity of steel moment-resisting frames considering randomness of yield strength

The purpose of this paper is to evaluate the energy absorption capacity of steel moment resisting frames considering randomness of member yield stress. It is well known that frames designed with weak beam strong column type mechanism show high ductility behavior, but the energy absorption capacity at the deformation level considered in the structural design process has not been discussed very well. In this paper, the energy absorption at the maximum drifi angle of O.O2rad was investigated based on Monte Carlo simulation under the static load condition. The analysis parameters are the number of stories, the number of spans and column overdesign factor (COF). Some conclusions obtained by this study are summarized as follows. 1) Average value, 100 lower limit value and 500 lower limit value of the energy absorption increase by controlling the range of randomness of member yield stress, and 2) the increasing percentage is positively conelated with the number of stories. 3) COF can be made smaller than basic frames' COF by controlling the range of randomness of member yield stress, especially with large number of stories and high value COF.