علي سپهوند

Self-centering braced steel frames are a new type of seismic bearing frames that can overcome the disadvantages of conventional frames while maintaining many advantages. In these frames, to increase the displacement capacity of the structure, the frame columns are allowed to be lifted easily from the foundation, and pre-tensioned cables are used at the height of the frame to eliminate permanent displacement in the building. In this research, the optimal seismic behavior of probabilistic centripetal bracing frames with rocking motion equipped with adjustable mass damper was investigated under seismic records near and far from the fault. For this purpose, first, a modeling was done in Appensis finite element software for verification and the obtained results were compared with the laboratory results of previous researches and the accuracy of the modeling was ensured. In the following, different frames were modeled for parametric study, totaling 6 models (three, six and nine floors) with and without adjustable mass damper. Push-over and time history analyzes were performed to check the performance of the frame and the effect of the presence of TMD was studied. In the following, by performing incremental dynamic analysis and drawing IDA curves and fracture curves as well as calculating the average fragility, the performance of frames with and without TMD under far and near field accelerometers was investigated and eva‎luated. The obtained results show that frames equipped with TMD perform better compared to frames without TMD under near and far field accelerometers. The average effect of TMD on the average fragility in a three-story frame in far and near earthquakes is 5% and 7%, respectively. While the average impact in the six-story frame is 8% in both the far and near areas. Also, in the frame of nine floors, the corresponding numbers are 22% and 10%, respectively. The increase of these values compared to the values obtained from the three and six-story frames indicates a more suitable TMD performance in the nine-story frame than the three- and six-story frame.

ارزيابي احتمالاتي، قاب مهاربندي، قاب مركزگرا، تحليل ديناميكي افزاينده، اجزا محدود

: Self-centering braced frames, Increamental dynamic analysis, Tunned mass damper, Finite element

Ali Sepahvand

Dr Vahid Broujerdian