تحليل رفتار لرزه اي داخل صفحه ديوار بنايي تقويت شده با روكش بتن مسلح

SEISMIC ANALYSIS OF THE IN-PLANE BEHAVIOR OF MASONRY WALL RETROFITTED WITH RC OVERLAY

Unreinforced masonry (URM) buildings are widely used in Iran and if their details do not conform to applicable standard, they maybe vulnerable to earthquake. One of the conventional techniques used in retrofitting of existing URM buildings consists of using reinforced concrete (RC) overlay. In this method concrete with a thickness of 3 to 5 cm is sprayed onto the surface of a masonry wall over a mesh of reinforcing bars. In this paper, effect of RC overlay on nonlinear in-plane behavior of confined masonry wall is studied by FEM using 2-D analytical program WCOMD, developed in Tokyo University. In this program, average constitutive models of reinforced concrete and masonry elements are used. In addition, to model cracks constant smeared crack method is used. In this paper, the reinforced masonry wall is modeled using masonry and RC elements as well as interface elements to model sliding between masonry and RC elements. Interface elements characteristic are defined based on nonlinear shear behavior of shear bars. Then, results of the numerical model are verified against available experimental results. After verification, a parametric study is carried out on confined masonry walls and the effects of compressive strength of confinement and size of openings on behavior of walls are studied.