Local deformation-based design of minimal-disturbance arm damper for retrofitting steel moment-resisting frames

This paper presents a design approach for seismic rehabilitation of frames having a beam-collapse mechanism using a technique termed minimal-disturbance seismic rehabilitation. This technique pursues enhancing the seismic performance of buildings with the intention of improving the continuity of business. It minimizes obstruction of the visual and physical space of building users and the use of heavy construction equipment and work requiring fire permit (welding/cutting). The developed design approach is simple to use. Yet it leads to designs that limit the beams' plastic rotations to allowable values, while minimizing the number of locations where devices are installed and the devise dimensions. Furthermore, the effectiveness of the design approach and the rehabilitation technique is numerically studied through retrofitting a four-story steel moment-resisting frame.