【摘要】 底框砖房是指底部一层全部或部分结构体系采用钢筋混凝土框架、上部多层采用砌体结构的混合结构体系.5.12汶川大地震灾区该类建筑应用非常广泛.基于灾区广泛的调查成果,分类总结了汶川地震中底框砖房的主要震害特征,即部分底框砖房表现出很差的抗震性能;过渡层普遍破坏严重甚至于完全坍塌;上部砌体整体相对于底部框架发生水平滑动.研究表明,过渡层的工作机理非常复杂,地震中的实际受力情况与设计所采用的受力状态有明显的区别,建议在现行规范要求的基础上提高过渡层的强度和延性要求;现行抗震规范对底框和上部砌体层刚度比的规定对于提高底框砖房的抗震性能具有重要意义,建议进一步考虑砌体和钢筋混凝土材料的不同力学性质来制定上下层刚度比范围;底框和上部砌体结构之间的可靠连接是保证底框砖房整体工作的前提;严格按现行抗震规范设计和施工的底框砖房能获得良好的抗震性能;部分底框砖房因其混杂的结构体系不利于抗震,建议在抗震设防地区禁止使用.更多还原

【Abstract】 Masonry structure with total or partial ground RC Frame is one kind of building structures,and the uppe stories of it are masonry structures and the ground floor is RC frame structure.This kind of structure style is widely used in the epicentral areas.In some cases,the ground floor vertical structure consisted of RC frames and masonry walls.A large number of these buildings suffered severe damage or even collapsed totally in the epicenter regions.In other cases,the ground floor vertical structure is consisted of RC frames with seismic walls and infill walls.However,some of them had perfect performance in the Earthquake.Many structural deficiencies and mistakes were highlighted,including:(1)transition layer(the first masonry structure layer)suffered more severe damaged;(2)these buildings with farraginous structure in ground floor had bad performance,and(3)poor consturction quality in RC frame or masonry walls led to severe damages.Finally,lateral stiffness ratio of the masonry structure transition layer to RC frame ground story was optimized following the difference of materials.The strength and the ductility of transition layer,as well as shear walls in the ground floor,are crucial in keeping the building standing during large earthquake.更多还原