FRP加固非延性钢筋混凝土框架结构的地震倒塌易损性分析

Seismic collapse fragility analysis for non-ductile RC frame structures retrofitted with FRP

采用增量动力分析方法,考虑3种不同的纤维增强复合材料(FRP)加固方案,对低多层非延性钢筋混凝土框架结构在FRP加固前后的地震倒塌易损性进行了分析。结果表明:整体加固方案可以有效提高非延性钢筋混凝土框架结构的抗地震倒塌能力;采用底层加固方案会使结构的薄弱层上移,不能提高结构的抗地震倒塌能力,反而降低了结构的地震倒塌安全裕度;随着非延性钢筋混凝土框架结构高度的增加,FRP的加固效果逐渐减弱。

Incremental dynamic analysis( IDA) was adopted to investigate the seismic collapse fragilities of low-tomedium-rise non-ductile RC frame structures before and after fiber reinforced polymer( FRP) rehabilitation by three schemes. Results show that the FRP rehabilitation scheme to strengthen the entire structure can effectively promote the seismic collapse resistance. The rehabilitation scheme only enhancing the lower stories of the structure cannot promote the collapse resistance but reduce the collapse safety margin since the initial weak story is transferred upside accordingly. With increasing the structural height,FRP rehabilitation contributes less to the improvement of the seismic collapse resistance of non-ductile RC frame structures.