الفهرس | Only 14 pages are availabe for public view |
Abstract Many bridges in the world are classified as deficient and in need of rehabilitation or replacement. Some of them are deficient because their load-carrying capacity is inadequate for today’s increased traffic load. To improve their efficiency and increase their load capacity, several methods can be used, one of them is the external prestressing. Moreover, to avoid corrosion problem that faced this type of strengthening, Fiber Reinforced Plastics (FRP) can be used in lieu of steel tendons. Within the different types of FRP, Parafil rope was established to be well suited for prestressing system, combining the benefits of light-weight, high strength, easy handling and efficient anchorage system. The lack of researches in the behavior of externally pre-stressed beams with FRP tendons, especially for continuous beams, prevents adequate utilization of this strengthening method. The objective of this research is to study the behavior of externally pre-stressed continuous beams with FRP tendons, with two factors: the value of the external prestressing force and the applied load configuration. Five R.C continuous beams with two spans were tested up to failure, one without any prestressing, and the rest strengthened externally using Parafil Ropes Type G, four beams were tested under two third point loading, and one beam under one concentrated load at mid span. Analytical investigations were also conducted to verifying equations in previous researches for calculating cracking and ultimate strength of continuous externally pre-stressed R.C. beams. |