ABSTRACT
In this investigation, at first, the behavior change of Braced Moment Resisting Frame (BMRF) system with respect to the employment of different diagonal tension braces in the form of various single story frames is investigated and the differences between the distributed and lumped plasticity approaches are considered. The formation and propagation of plastic hinges and the corresponding displacement histories for different single story BMRFs are displayed and the effects of brace stiffness on the behavior of MRFs and the drift reductions are discussed. Then by developing an analytical model and corresponding correction process, the behaviors of severalmulti storyBMRFs in the
form of 2, 4 and 6 story buildings having different stiffness and brace sizes under regular lateral loadings are studied. Unsuitable mechanisms, such as frame mechanism (elastic brace behavior), brace mechanism (similar to MRF collapse manner), and soft story mechanism (inappropriate full plastic hinge formation in one story) are evaluated by developing an example problem in a 2 story BMRF system.
