用拆除墙段建造的砖砌体结构地震易损性分析

Seismic vulnerability analysis of masonry structures built with removed walls

用拆除墙段建造新砌体结构在实现拆除墙段再利用的同时,推进了砌体结构工业化拆除及建造的进一步发展。为研究用拆除墙段建造的砖砌体结构的抗震能力,分析了用拆除墙段建造的砖砌体结构与普通砖砌体结构的异同,以构造柱间距、结构层数和砌体强度为基本参数,选取地震峰值加速度作为地震动强度指标,最大层间位移角作为结构损伤指标,选取了20条地震动记录对砖砌体结构模型进行了增量动力分析。基于所建立的砖砌体结构地震易损性曲线和地震破坏矩阵,发现较相同条件下的常规砖砌体结构,用拆除墙段建造的砖砌体结构的抗震性能得到明显改善,这主要是拆除墙段间连接所用的构造柱相对较密导致的;结构层数和砌体强度直接影响着结构的抗震能力,建议拆除墙段再利用时,结构总层数和总高度不宜超过GB 50011的规定,并合理评定拆除墙段的力学性能及完好性,同时保证使用拆除墙段建造的砌体结构的抗震措施不低于相应抗震设防烈度要求下的新建砌体结构。

The construction of masonry structures with removed walls can realize the reutilization of the removed walls and promote the further development of industrialized demolition and construction of masonry structures.To study the seismic resistance of masonry structures built with removed walls,the similarities and differences between masonry structures built with removed walls and ordinary masonry structures were analyzed.Twenty ground motion records were selected for incremental dynamic analysis of brick masonry structure model with structural column spacing,number of stories,and masonry strength as basic parameters,peak ground acceleration as ground shaking strength index,and maximum inter-story displacement angle as structural damage index.Based on the established seismic vulnerability curves and seismic damage matrix of brick masonry structures,it was found that the seismic performance of brick masonry structures built with removed walls was significantly improved compared with conventional brick masonry structures under the same conditions,which was mainly due to the relatively dense structural columns used for the splicing of the removed walls.The number of stories and masonry strength directly affected the seismic capacity of the structure.It is recommended that the total number of stories and total height of the structure should not exceed the requirements of GB 50011 when reusing removed walls,and reasonably assessment of the mechanical properties and integrity of the removed walls should be conducted.It is also necessary to ensure that the seismic measures for masonry structures built with removed walls are not lower than those for new masonry structures under corresponding seismic intensity requirements.