Seismic retrofit of asymmetric structures using steel plate slit dampers

• A procedure for estimating proper amount of steel plate slit dampers in low-rise asymmetric structures was developed.
• The design objective was set to keep the ductility demand within a given target point.
• The structures installed with the slit dampers showed satisfactory inter-story drifts in both the stiff and the flexible edges.

A seismic design and retrofit procedure were developed for estimating the proper amount of steel plate slit dampers required to keep the seismic response of low-rise asymmetric structures within a given target performance level. Parametric studies for displacement response of a single story plan-wise asymmetric structure were conducted with varying eccentricities between center of mass and center of stiffness. Then a procedure was developed to distribute the damper based on the ductility demand of the structure. The procedure was applied to install slit dampers at proper locations of low-rise structures with horizontal and/or vertical irregularities subjected to an earthquake load. According to the nonlinear static and dynamic analysis results, the structure with hysteretic dampers installed in accordance with the proposed procedure showed satisfactory inter-story drifts in both the stiff and the flexible edges when they were subjected to the design level seismic load.