Experimental investigation on the NSM retrofitted adobe walls under cyclic lateral loading

Document Type : Research Article

Authors

1 Civil Eng. Dept.,Yazd University

2 Yazd University / member of Scientific Board

Abstract

In masonry structures, load bearing walls play a crucial role in the overall seismic performance and structural integrity. Thus, their retrofitting strategies typically involve retrofitting of their walls. One of the retrofitting technique can be using steel or composite materials in the form of near-surface-mounted (NSM) reinforcement. Despite being considered as masonry structures, there have been fewer investigations on seismic retrofitting of the adobe structures. In the current study, the efficiency of NSM steel rebars in improving the seismic performance of adobe wall is investigated through experimental investigations. The test specimens were comprised of four scaled-down (1/3) adobe walls measuring 1000 mm in length, 800 mm in height, and 200 in thickness. Retrofitting bars, in the form of two perpendicular NSM meshes, were applied on both sides of the walls. The specimens were tested under an incremental in-plane cyclic loading reversals applied simultaneously with a constant axial pre-compression of 0.1 MPa. Based on the obtained experimental results, NSM technique accompanied with the proposed anchorage system had a considerable effect in improving the lateral strength, lateral in-plane stiffness, and ductility of adobe wall specimens.

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Main Subjects


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