The three unreinforced masonry walls with opening(including two walls strengthened by the prestressing force applied to the vertical and diagonal prestressing tendons,one companion control wall) subjected to lateral cyclic loading were tested.The crack development,yielding and breakage of the three walls were presented,including discussion on the seismic performance in terms of failure processes and patterns,hysteretic characteristics and skeleton curve,ductility and stiffness degradation.The experimental results indicated that the typical failure mode of prestressed wall was shear-compression failure;the vertical prestressing technique was significantly effective in improving cracking load;the diagonal prestressing technique was more significantly effective in increasing the ultimate load and lateral stiffness. The initial stress of the prestressing tendon had a linear relationship,the stress of the vertical and diagonal prestressing tendons were increased by 146.15 and 154.73 MPa,respectively.%对二榀体外预应力加固开洞砖墙体(垂直加固、斜交叉加固)和一榀对比墙体进行拟静力试验,考察砖墙体裂缝开展、屈服及破坏等受力全过程,分析了其滞回特性、延性、骨架曲线、刚度退化等抗震性能.结果表明:预应力墙体主要表现为剪压破坏形态;垂直预应力加固能显著提高墙体的开裂荷载,而斜交叉预应力筋加固方式可以更有效提高其极限荷载及后期抗侧刚度;初期预应力筋应力呈线性关系变化,垂直、斜交叉外侧筋最大应力增量分别为146.15和154.73 MPa.
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