| According to the Federal Highway Administration of the United States Department of Transportation, the US has an inventory of over 583,000 bridges. Among them, about 173,000 bridges are classified as either functionally obsolete or structurally deficient. Reconstruction of these bridges will cost about 200 billion dollars. However, annual expenditures in this field are insufficient to overcome annual deterioration. This situation has led to a need to finding alternate methods—strengthening or retrofitting methods. This study focuses on using a new technique of repair and strengthening of concrete beams using carbon fiber reinforced polymer including (i) resistance to fire, (ii) resistance to UV radiation, (iii) easy handling and no order or toxin during construction or curing, and (iv) better chemical bonding to concrete.; This research has investigated the static and fatigue behavior of RC beams strengthened with CFRP sheets bonded by the inorganic matrix to those bonded by organic matrix, an additional thirteen RC beams were bonded by organic matrix. Among them, four were used for static test and nine for fatigue test. Five RC beams were also constructed for control beams: one for the static test and 4 for the fatigue test.; Crack patterns, failure modes, strength improvement/behavior, stiffness behavior, strain behavior and fatigue lives behavior were studied. Results show that the behavior of RC beams bonded by the inorganic system is different from those bonded by the organic matrix. In addition, the results show that the fatigue lives of RC beams strengthened with CFRP sheets yielded the Weibull probability distribution.; Through this study, models to predict ultimate moment capacity, deflection, stress-strain behavior, and fatigue lives corresponding to different failure probability were developed. The suggested models can predict the behaviors of RC beams bonded by both the inorganic and organic matrix systems well.; Finally, some suggestions regarding the application of this research to AASHTO were made. |
