Retrofitting of Unreinforced Masonry Walls for Out-of-Plane Bending

伊赫萨尼最近发生的9421950次地震表明，未加固的砖墙结构构成了生命安全危险。提出了用纤维复合材料加固城市道路混凝土墙体。复合材料的柔韧性、轻质和高抗拉强度使其成为加固砌体结构的理想材料。最近的一项研究表明，静力加载可以显著提高强度和延性。本研究项目的主要目的将是研究纤维复合材料加固的无筋砖墙的平面外循环性能，并制定现有URM结构的分析和设计程序或抗震加固。将对六个墙体试件进行测试，每个试件大约8英尺宽，10英尺高。我们将考察两种不同的高厚比(h/t=14和28)，它们是由一个或两个怀特砖构成的。涂在墙面上的复合织物要么完全覆盖墙的两面，要么作为垂直条带分开并交错地应用在墙的相对面上。测试结果将被用来制定城市轨道交通结构加装的设计指南。这项拟议的研究将与密歇根大学的一项平行研究密切协调，该研究调查纤维增强URM墙的平面内循环行为。***

9421950 Ehsani Recent earthquakes have demonstrated the life safety hazard posed by unreinforced masonry (URM) wall structures. It is proposed to strengthen the URM walls by fiber composites. The flexibility, light weight and high tensile strength of composites makes them an ideal material for strengthening masonry structures. A recent study has demonstrated that significant increases in strength and ductility could be achieved for static loading. The primary objective of this research project will be to study the out-of-plane cyclic behavior of unreinforced masonry (URM) walls strengthened with fiber composites and to develop analysis and design procedures or seismic strengthening of existing URM structures. Six wall specimens, each approximately 8 ft wide and 10 ft tall, will be tested. Two different height to thickness ratios (h/t = 14 and 28) constructed of one or two wythes of bricks will be examined. Composite fabrics epoxied to the wall will either fully cover both faces of the wall, or will be applied as vertical strips spaced apart and staggered on the opposite faces of the wall. Test results will be used to develop design guidelines for retrofitting of URM structures. The proposed research will be closely coordinated with a parallel research investigating the in-plane cyclic behavior of fiber reinforced URM wall at the University of Michigan. ***