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Ductility of Reinforced Concrete Masonry Shear WallsShedid, Marwan Mohamed Tarek January 2006 (has links)
Pages vi, 34, 68, 158, 208 and 226 are blank and therefore omitted. / <p> To assess the ductility of shear walls under earthquake loading, more experimental evidence is strongly needed. Ductile response can be achieved through the development of a flexural plastic hinge at the base characterized by yielding of the vertical reinforcement. The length of the plastic hinge and the ultimate curvatures within this region are the essential parameters affecting the ductility and ultimate displacements of reinforced masonry shear walls. The discrepancies in existing information regarding the length of plastic hinges and ultimate curvature may be attributed to the effects of many shear wall parameters such as distribution and amount of vertical and horizontal steel, level of axial load, and wall aspect ratio. </p> <p> The focus of this study was to evaluate the effect of different parameters on plastic hinge length, energy dissipation, and on general ductility of masonry shear walls. To address the aforementioned goal, six fully grouted reinforced masonry walls were tested under fully reversed cyclic lateral loading. All walls were designed to experience ductile flexural failure. The test matrix was chosen to investigate the effects of the amount and distribution of vertical reinforcement and the level of applied axial load on the lateral loading response and ductility of reinforced masonry shear walls. To examine the effects of these parameters, measurements of the applied loads, vertical and horizontal displacements as well as strains in the reinforcing bars were used to analyze the behaviour of the walls. Also, from these measurements, other quantities used in analysis were determined, including displacement ductilities, curvature profiles, energy dissipation and equivalent plastic hinge length. </p> <p> The results show high ductile capability in the plastic hinge region and very little degradation of strength for cyclic loading. High levels of energy dissipation in the reinforced concrete masonry shear walls were achieved by flexural yielding of the vertical reinforcement. All walls showed increasing hysteretic damping ratios with increase in displacement. Results showed that displacement ductility and energy dissipation were highly sensitive to increases in amount of vertical reinforcement but were less dependent on the level of applied axial stress. The results of this study also showed that the measured plastic zone length decreases with increase of the amount of reinforcement while it is almost the same for the different levels of axial stress. Based on the test results, it was shown that reinforced concrete masonry shear walls may be utilized in high intensity seismic areas with performance meeting or exceeding current expectations. </p> / Thesis / Master of Applied Science (MASc)
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