<strong>ملخص الدراسة:</strong>

This study investigates the flexural capacity, deflection and crack patterns of reinforced concrete beams repaired by application of four repair materials, Ultra High Performance Concrete, Ultra High Performance Fiber Reinforced Concrete, Ordinary Portland Concrete, and special repair materials for repair of three types of damages that can occur in construction. These include over loading cracks, honeycombing, and spalling of concrete cover due to elevated temperature. It is also intended to assess the feasibility of using these repair materials in repair and strengthening of damaged reinforced concrete beams. A series of four point flexural tests was conducted on both damaged and undamaged reinforced concrete beams to evaluate the performance of the damaged reinforced concrete beams after application of the repair materials. The conducted tests yielded complete load–deflection curves from which the increase in flexural capacity was evaluated. The results show that the repair materials are capable increasing the flexural capacity, deflection and improving crack pattern, and are effective in strengthening and repair of damaged RC beams. The results of the investigation will be used to develop design guidelines governing the use of these repair materials in the field of repair and strengthening of damaged reinforced concrete beams. The cracked beams which were repaired using UHPC, UHPFRC, OPC and SRM developed flexural strengths 8, 19, 3.17, 11% respectively, higher than the undamaged beams. The honeycombed beams which were repaired using UHPC, UHPFRC, OPC and SRM developed flexural strengths 19, 30, 1.50, 27% respectively, higher than the undamaged beams. And the heated beams which were repaired using UHPC, UHPFRC, OPC and SRM developed flexural strengths 1.50, 6.60, 0.00, 3.70% respectively, higher than the undamaged beams.

<strong>توثيق المرجعي (APA)</strong>

ملخص الدراسة:

This study investigates the flexural capacity, deflection and crack patterns of reinforced concrete beams repaired by application of four repair materials, Ultra High Performance Concrete, Ultra High Performance Fiber Reinforced Concrete, Ordinary Portland Concrete, and special repair materials for repair of three types of damages that can occur in construction. These include over loading cracks, honeycombing, and spalling of concrete cover due to elevated temperature. It is also intended to assess the feasibility of using these repair materials in repair and strengthening of damaged reinforced concrete beams. A series of four point flexural tests was conducted on both damaged and undamaged reinforced concrete beams to evaluate the performance of the damaged reinforced concrete beams after application of the repair materials. The conducted tests yielded complete load–deflection curves from which the increase in flexural capacity was evaluated. The results show that the repair materials are capable increasing the flexural capacity, deflection and improving crack pattern, and are effective in strengthening and repair of damaged RC beams. The results of the investigation will be used to develop design guidelines governing the use of these repair materials in the field of repair and strengthening of damaged reinforced concrete beams. The cracked beams which were repaired using UHPC, UHPFRC, OPC and SRM developed flexural strengths 8, 19, 3.17, 11% respectively, higher than the undamaged beams. The honeycombed beams which were repaired using UHPC, UHPFRC, OPC and SRM developed flexural strengths 19, 30, 1.50, 27% respectively, higher than the undamaged beams. And the heated beams which were repaired using UHPC, UHPFRC, OPC and SRM developed flexural strengths 1.50, 6.60, 0.00, 3.70% respectively, higher than the undamaged beams.

توثيق المرجعي (APA)