黏滞阻尼器的优化布置及其在高层钢结构加固中的应用

The optimal layout of dampers is an important part of the structural damping design process, which usually needs to be accomplished by multiple dynamic response calculations. To this end, a design procedure was proposed to determine the reasonable placement of dampers by structural static analysis, and to be able to quickly calculate the additional damping ratio of the optimization scheme. The proposed procedure was applied to the seismic retrofitting design of a 29-story steel building located in Shinjuku, Tokyo. The acceleration time history data of some floors recorded by the strong earthquake observation system of the building during Great East Earthquake on March 11, 2011, were analyzed, and the reliability of the established nonlinear numerical model was verified based on the analysis results. The existing high-rise structure was retrofitted by the proposed procedure, and the optimal arrangement schemes of 64 dampers in two directions and the additional damping ratio were obtained. The results were verified by the dynamic analysis method. Considering the effect of long-period and long-duration seismic ground motions, dynamic elasto-plastic time-history analysis was conducted to evaluate the seismic performance of the damped structures. The analysis results show that the damping effect of the damper optimization scheme is obvious, and the overall seismic response and component damage of the controlled structure are greatly reduced compared with those of the non-damped scheme. The seismic optimization scheme effectively improves the non-uniform floor deformation of the high-rise steel structure, and the inter-story drift ratio meets the performance requirement of less than 1/100. The plastic ratio of most steel braces and steel beams is reduced to less than one after adopting the damping optimization design.