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

最近的地震已经证明了无筋砌体（URM）墙体结构对生命安全的危害。提出了用纤维复合材料加固URM壁的方法。复合材料的柔韧性、重量轻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，在静载荷下，强度和延展性可以显著提高。本研究项目的主要目标是研究用纤维复合材料加固的无加固砌体墙的面外循环行为，并开发现有无加固砌体结构的抗震加固分析和设计程序。将测试六个墙体样本，每个约8英尺宽，10英尺高。两种不同的高度厚度比（h/t = 14和28）将由一种或两种砖块构成。环氧化的复合织物将完全覆盖墙壁的两面，或者将作为垂直条应用于墙壁的相反面。测试结果将用于制定URM结构改造的设计指南。拟议的研究将与密歇根大学的一项平行研究密切协调，该研究调查了纤维增强URM壁的面内循环行为。＊＊＊

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. ***