自复位耗能摇摆架加固软弱底层框架抗震性能

为改善软弱底层框架的层间变形和能量耗散模式,提出一种结合预应力钢绞线和装配式BRB的自复位耗能(SCED)摇摆架加固方案.对加固后体系进行受力性能分析,并建立有限元模型对SCED摇摆架-软弱底层框架的性能进行研究.结果表明,SCED摇摆架能明显改善软弱底层框架的破坏模式、抗震性能、自复位性能和变形模式,但是钢绞线和装配式BRB对层间变形有不利的影响,建议层间变形为控制目标的结构采用纯摇摆架加固,而侧向变形为控制目标的采用SCED摇摆架.

Structural seismic performance of self centering energy dissipative rocking frame for strengthening soft first story RC frames

To improve the distribution of inter-story drift and energy dissipation mode of soft-first-story RC frame, this paper presented a self-centering energy dissipative (SCED) rocking frame combining pre-stressed wires and assembled BRB. The mechanical performance of the system was studied and thereby the design method of pre-stressed wires and assembled BRB was presented. The finite element model was built up first and then was used to study the performance of SCED rocking frame for strengthening soft-first-story RC frame. The results indicate that the structures retrofitted by SCED rocking frames can apparently improve their failure modes, seismic performance, self-centering performance and deformation modes. However, the pre-stressed wires and assembled BRB have adverse effects on the story drift. It is suggested that the structure with the goal of controlling story drift should be reinforced with pure rocking frame, and the structure with the goal of controlling lateral deformation should be the SCED rocking frame. This paper can provide a design reference of SCED rocking frame for strengthening soft-first-story RC frame.