Retrofitting steel moment frames by using the cable bracing

In this paper, the behavior of retrofitted steel moment frames with bracing has been investigated. Braces include double-channel cross brace, cross braces with cable and brace with two cables passed through a cylindrical steel sheath at the location of the cables. Nonlinear analysis of frames has been carried out under cyclic loading with increasing amplitudes. Comparison of numerical analysis results with laboratory data shows the accuracy of finite element models. By determining the hysteresis and plasticity behavior of the frames, advantages and disadvantages of each of the retrofitting methods have been examined. The results have shown the use of double channels and cables to retrofit the frame increases the initial hardness and final load of the frame considerably compared to the moment frames and reduces its ductility. In frame with sheathed cable brace, the initial hardness was the same with the moment frames and the frame has been shown to have ductile behavior.