الفهرس 
Ch.1 IntroductionOnly 14 pages are availabe for public view
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Abstract
1:-Introduction: - There are many structural advantages to use lightweight concrete (LWC) as a building material. The reduction of dead weight due to a lower density of concrete can improve the seismic resistance capacity of building structures. Furthermore, the smaller and lighter elements of precast concrete are preferred because the handling and transporting system becomes less expensive. Offshore structures which mostly used for oil production, require LWC elements to provide easier towing and greater buoyancy. Openings are frequently placed in the web region of reinforced concrete (RC) deep beams to facilitate essential services such as access, conduits, AC lines, etc. These openings may interrupt the load path and can cause a sharp decrease of serviceability and strength of RC deep beams. Though the strength evaluation and reinforcement details around openings are essential considerations, their design details have not been yet provided by most codes of practice particularly for LWC. 2:- Research scope: - Although the practical applications of lightweight concrete have gradually increased in building structures, extensive experimental investigations and strut-and-tie modeling have focused mainly for reinforced normal weight concrete NWC deep beams. In this study, in contrast, an experimental work (followed by a strut-and-tie modeling) was carried-out on reinforced lightweight concrete LWC deep beams with web openings. 3:- Research objectives: - Obviously, openings are provided to deep beams to enable essential services and accessibilities to pass . In structures, openings can reduce the area needed for the inclusion of these services and increase the useful space within the structure. This study focuses also on the design and detailing of experimental program for lightweight RC, deep beams with and without openings utilizing the considered strut-and-tie modeling method. 4:- Steps of Study: - The present experimental investigation reports test results of six lightweight reinforced concrete deep beams with web openings including a reference solid beam. The beams have an overall depth, h, of 600mm, a span length, L, of 1000mm, and a web thickness, b, of 160mm. The main parameter considered in this investigation was the size of web openings. Three specimens with web openings having the same depth, m2h, of 180mm, while the other beams with web openings having the same width, m1a, of 200mm. The used concrete in casting the specimens has a cylinder compressive strength of 32MPa. The beams were tested to failure under two-point loads that lie at beams shear span to.