Investigating an Optimal Computational Strategy to Retrofit Buildings with Implementing Viscous Dampers

Abstract

AbstractCivil engineering structures may seriously suffer from different damage states result of earthquakes. Nowadays, retrofitting the existing buildings is a serious need among designers. Two important factors of required performance level and cost of retrofitting play a crucial role in the retrofitting approach. In this study, a new optimal computational strategy to retrofit structures by implementing linear Viscous Dampers (VDs) is investigated to achieve a higher performance level with lower implementation cost. Regarding this goal, a Tcl programming code was developed with the capability of considering damaged structure due to earthquake-induced structural pounding. The code allows us to improve structural models to take into account the real condition of buildings using both MATLAB and Opensees software simultaneously. To present the capability of this strategy, the 3-, and 6-story colliding Steel Moment-Resisting Frames (SMRFs) were selected. Incremental Dynamic Analysis (IDA) was performed based on the interstory drift ratio of floor levels as engineering demand parameter, and Sa(T1) as intensity measure. Interstory median IDAs of floor levels of colliding SMRFs were plotted to find out the floor level prone to damage and to retrofit only this floor level instead of all stories. The results show that implementing only two linear VDs with a cost of two units can achieve a higher life safety performance level in the case of 3-, and 6-story SMRFs. Moreover, the proposed computational strategy can be used for any structure (with and without pounding conditions), and in all performance levels prescribed in FEMA 356 code. KeywordsOptimal computational strategyOpensees programmingRetrofitting of buildingsViscous damperStructural poundingEarthquakes