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Abstract
Flexural behavior of filled fibrous ferrocement U shape beams with various types of concretes The main objective of this research is to study the flexural behavior of U shape fibrous ferrocement concrete beams filled with various types of concretes with high strength, crack resistance and high ductility and energy absorption properties. This research will include six chapters. Twenty four beams will be cast and tested under flexural loadings. The study includes six chapters will be as follows: Chapter 1 includes introduction, objectives and summary of the main chapters of the thesis. Chapter 2 includes an extensive literature review of the previous research study in the field of reinforced concrete beams subjected to impact loadings. Chapter 3 includes details of the experimental test program of casting and testing of twenty four reinforced concrete beams reinforced with various types of reinforcing materials and the used instrumentations Chapter 4 consists of the obtained results and discussions. Chapter 5 includes the mathematical and non linear finite element analysis. Comparison agreement will be arrived with the experimental results. Chapter 6 includes summary of the conclusions reached and suggestions of future work. This thesis presents the results of an experimental investigation aimed at introducing a new construction technique for reinforced concrete beams. The main objective of this research is to study the flexural behavior of U shape fibrous ferrocement concrete beams filled with various types of concretes with high strength, crack resistance and high ductility and energy absorption properties.. In this method, steel meshes are used as a viable alternative to ordinary steel bars commonly used in reinforcing concrete beams. The proposed method is so simple that it dose not require neither complicated technology nor light-skilled labors. The results of both experimental and analytical investigation to examine the effectiveness of this method including the cracking patterns, deformations, and strength characteristics of the tested developed ferrocement beams are reported and discussed. To improve the properties of the mortar used in producing ferrocement beams, a study was conducted to examine the effect of silica fume on the properties of mortar and to determine its optimum percentage as a cement replacement. The results of this study are also presented and discussed. Twelve reinforced concrete beams were cast and cured for 28-days before testing. The dimensions of all test specimens were kept constant. The length of the beams was 1000 mm, 100 mm width and 100 mm depth but reinforced with different volume fraction of steel reinforcement and metallic and non metallic meshes.. The conventional concrete beam and ferrocement beams reinforced with expanded metal mesh and galvanized welded steel mesh applying different reinforcement schemes. The reinforcement schemes included applying one layer of expanded metal mesh with two ordinary steel bars at the tension face, one and two layers of expanded metal mesh in the tension face, one layer and two layers of welded steel mesh were also employed. ferrocement ribs. All test specimens were tested under four line loadings with simply supported over a span of 900 mm until failure. All the deformation characteristics, cracking patterns and strengths were extensively measured at all stage of loadings. A simple computer program used to predict the behavior of these developed beams. The experimental results were used to verify the predicted results obtained using computer program. The test results of the ferrocement mortar revealed that (10%) percent is the optimum replacement percentage of cement by silica fume for water/cement ratio of (0.30). The analytical and experimental results of reinforced ferrocement beams in filled with various types of materials emphasized that, better control of cracking behavior for all tested beams compared to control beams. The ductility ratio and energy absorption properties of the tested beams were improved by this method of reinforcement. In general the experimental results proved the effectiveness of expanded metal mesh and welded steel mesh in reinforcing ferrocement beams. Ferrocement beams filled with various types of materials were developed with high strength, ductility and energy absorption properties and lighter in weight which could be useful for developed and developing countries alike.