الفهرس 
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Abstract
This research presents an experimental and analytical investigation in the flexural behavior and Ductility of reinforced self-compacting lightweight concrete (LWC) Continuous beams. LWC was obtained through using of polystyrene foam as a partial aggregate’s replacement to reduce the concrete dry unit weight from 23.0kN/m3 to 18.5kN/m3.A total of five medium scale reinforced LWC Continuous beams were cast and tested under concentrated load at the mid-span. All tested beams failed in flexure, hence, experiencing the traditional crack patterns. The beams had 120mmx250mm rectangular cross-sectional dimensions with overall length of 3000mm over a clear span of 2200mm. The specimens` continuity over the supports realized through two RC end blocks of dimensions 120mmx400mmx750mm.the only difference between the tested beams was the percentage of –ve to +ve reinforcement to allow for moment redistribution. As for the theoretical investigation in this study, an analytical model using the FE method was developed for the tested specimens using the nonlinear package “Abaqus6.7”. The model was also validated through comparisons with key experimental results and, hence, can be used with confidence to conduct future parametric studies. The model was then verified against the experimental results and showed very good agreement with the test data.
The analytical investigation was extended to include a study on the element level to determine the maximum and minimum permissible reinforcement ratios and provide a comparison with the limits provided by the ECCS 203-01.
To fulfill the previously mentioned objectives, this research was divided into the following chapters:
• Chapter (1) is an introduction to this research discussing the importance, objectives and the scope of the research program.
• Chapter (2) presents a historical background on both lightweight and self-compacting concretes as well as the definition of LWC and the mechanism of achieving SCC. The chapter further presents a review of the available literature on the ductility, modulus of elasticity, compressive and tensile strengths and stress-strain relationships of LWC. The chapter is concluded by presenting the motivation and need of the current research in light of the previous work done on the topic.
• Chapter (3) presents the experimental program through describing its phases, the formwork, material properties, fabrication, test specimens, test setup, measurement devices, and loading scheme.
• Chapter (4) discusses and analyzes the test results and observations by presenting the tested mechanical properties of LWC as well as the results of the tested beams which include crack patterns, cracking and failure loads, deflections, compressive concrete strains and tensile steel strains.
• Chapter (5) this chapter introduces a description of the FE program utilized to simulate the specimens. This description includes types of elements, material definition, solution strategy, loading and boundary conditions.
• Chapter (6) this chapter introduces the FE results obtained from the program and discussion of the results from the program. Also a comparison is held between the experimental and finite element results.
• Chapter (7) presents the summary and the conclusions of the research and the suggestions for future studies.