الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
Passing services ducts through web openings in floor beams, instead of underneath the beam soffit, reduces the required overall floor height and, consequently, decreases the construction costs. Beam-column joints are openingery important part of every reinforced opening structure and have great influence on the stiffness and stability of the whole structure especially in seismic zones. However, the presence of such openings in reinforced opening beams web affects their structural behavior. Besides, rigorous analysis of R.C beam-Column joint with beam web openings under cyclic loading requires nonlinear finite element analysis and Experimental work which is not typically done by design engineers. Moreover, national and international codes of practice do not have provision especially for design of this case. As a result, research effort in developing design guidelines for beam-column joint with openings under cyclic loading are greatly needed. The present thesis is a contribution in this direction. For this purpose, an experimental work program )ten specimens) is conducted together with numerical analysis using Non-linear finite element models ANSYS was developed, for openingerification extensive parametric study, was conducted to investigate the effect of openingarious parameters including horizontal reinforcement at top and bottom of the web opening to maximum reinforcement ratio “R”, openingertical reinforcement at left and right of the web opening to area of reinforcement stirrups (R´), compression and tension main reinforcement of beam to maximum reinforcement ratio “α”, opening proximity to support (S/d), relative opening height (H_o/d), relative opening length (L_o/d) and reinforcement stirrups in joint core (connection between beam & column). Parametric study applied to beam column joint with inertia of column / inertia of beam (〖I_c/I〗_b= 0.81), beam column joint with inertia of column / inertia of beam (〖I_c/I〗_b= 0.51) and case study beam column joint with inertia of column / inertia of beam (〖I_c/I〗_b= 0.15). In order to investigate the effect of the previous parameters on the behaviour of specimens, the specimens are classified into ten groups, each with a particular parameter. Comparison and analysis of results were made to investigate the effect of parameters on reinforced opening beam-column joint with web openings under cyclic loading. A formula was suggested to evaluate the ultimate capacity of beam column joint having a single square or rectangular opening in beam web and subjected to cyclic loading.
Based on the conducted parametric study, it was found that the case of beam depth less than column length, the cracks will propagate in beam, and the plastic hinged will be formed in the beam which will cause partially failure in beam-column joint, the presence of web opening produces earlier cracks at opening location. These cracks increase in number and propagate continuously with the increase in applied load and lead to earlier failure. Compared to similar beams without web openings, at any particular load, both the number of cracks and the maximum deflection increase with the opening height, opening length, and opening proximity to support. The failure mode of beam column joint with web opening some cases may be classified as joint core failure it is critical cases we should avoid that. Finally, a special reinforcement details (around the opening) is suggested to increase the strength of the beams that are mostly affected by presence of the opening. It is found that such details can improve the ultimate capacity. An empirical equation is suggested to evaluate the ultimate capacity of beam-column joint with web opening. Also, general guidelines were suggested for location of openings in beam web.