Repair of heat-damaged RC shallow beams using advanced composites
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Several repair techniques for restoring the structural capacity of heat-damaged high-strength reinforced concrete shallow beams using advanced composites are proposed. A series of 16 under-reinforced concrete hidden beams were cast, heated at 600°C for 3 h, repaired, and then tested under four point-loading. Tests were conducted to study the effectiveness of externally applied composite materials on increasing the flexural capacity of beams. The composites used include high strength fiber reinforced concrete jackets; ferrocement laminates; and high-strength fiber glass sheets. The beams repaired with steel and high performance polypropylene fiber reinforced concrete jackets regained up to 108 and 99% of the control beams’ ultimate load capacity, with a corresponding increase in stiffness of up to 104 and 98%, respectively. The beams repaired with fiber glass sheets and ferrocement meshes regained up to 126 and 99% of the control beams’ ultimate load capacity, with a corresponding increase in stiffness of up to 160 and 156%, respectively. Most of the beams repaired showed a typical flexural failure with very fine and well-distributed hairline cracks in the constant moment region.
KeywordsRepair Heat-damaged beams Fiber Concrete
The authors would like to acknowledge the support received from the deanship of scientific research of University of Science and Technology at Jordan, and the assistance of the technicians at the engineering workshop and civil engineering laboratories.
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