Research on reinforcing method for masonry buildings in developing countries with high seismic activity

为了提高发展中国家砌体建筑的抗震安全性，对拉丁美洲国家砌体建筑普遍采用的承压砌体墙体体系进行了抗震性能改进试验研究。研究结果总结如下：1。约束砌体墙的抗震性能受弯破坏1)砌体墙与R/C围柱之间安装的钢筋和水平墙钢筋对墙体的抗弯强度不起作用。然而，这两种方法对墙体的延性都是有效的，特别是在低竖向轴向荷载作用下。2)用现有的加筋砌体墙的极限抗弯强度方法可以预测墙体的极限抗弯强度。横向墙约束砌体墙在两个方向水平力作用下的抗震性能1)连接筋和水平墙钢筋抑制墙体连接处竖向裂缝的增长。2)R/C围柱对墙体抗剪强度有正向影响。3)连接钢筋和水平墙体钢筋对墙体延性有效。4)横向水平荷载降低了墙体的面内水平承载能力。5)墙体的延性不受横向水平荷载的影响。水平墙配筋对墙体抗剪强度和变形能力的影响1)水平墙配筋对墙体抗剪强度有正向影响。2)砌体墙体加装水平钢筋可提高墙体的变形能力。3)墙体的抗剪强度和变形能力不受水平配筋量的影响。

In order to improve seismic safety of the masonry buildings in the developing countries, an experimental research for improving seismic performance of the confined masonry wall system, which is widely accepted in masonry buildings in Latin American countries, was carried out. Results of the research are summarized as follows.1.Seismic performance of confined masonry wall failed in flexure1)Connection bar, which is installed between brick masonry wall and R/C confining column, and horizontal wall reinforcing bar are not effective for the flexural strength of the wall. However, both of them are effective for the ductility especially in the wall subjected to lower vertical axial load.2)Ultimate flexural strength of the wall can be predicted by an existing method for the reinforced masonry walls.2.Seismic performance of confined masonry wall with transverse walls subjected to horizontal forces in two directions1)Connection bar and horizontal wall reinforcing bar restrain growth of the vertical cracks formed at wall connections.2)R/C confining column gives positive effect on shear strength of the wall.3)Connection bar and horizontal wall reinforcing bar are effective for the ductility of the wall.4)In-plane horizontal load carrying capacity of the wall is decreased by transverse horizontal loading.5)Ductility of the wall is not decreased by transverse horizontal loading.3.Effect of horizontal wall reinforcing bar on shear strength and deformation capacity of the wall1)Horizontal wall reinforcing bar gives positive effect on shear strength of the wall.2)Deformation capacity of the wall is improved if the horizontal reinforcing bars are installed in the masonry wall.3)However, clear differences due to the amount of horizontal reinforcing bars were not observed in shear strength and deformation capacity of the wall.