Repair of Heat-Damaged Reinforced Concrete T-Beams Using FRC Jackets

Journal Article
J.,, Shannag, M. . 2007
Publication Work Type: 
Research, Magazine of Concrete Research
Pages: 
223-231
Publication Abstract: 

A series of sixteen under-reinforced concrete T-beams were cast, heated at 600°C for two and a half hours, repaired, and then tested under four-point loading to study the effectiveness of using externally applied highstrength fibre reinforced concrete jackets as a method of increasing flexural capacity of beams. The overall response of the beams loaded up to failure, the onset of cracking, and cracking pattern, serviceability, stiffness and ductility were described. Four types of fibres were used, glass, high performance polypropylene, hooked end steel and brass coated steel with fibre content ranging from 1 to 2%. The beams repaired with steel fibre reinforced concrete jackets applied at the sides of the beams’ web and the bottom of the flange, exhibited a substantial improvement in their flexural behaviour compared to control (undamaged) ones. They regained a large proportion of the control beams ultimate load capacity, and showed a typical flexural failure with an increase in the first cracking load. The beams repaired with high performance polypropylene and glass fibers exhibited a marginal improvement in their flexural behaviour compared to control ones with a typical flexural failure and a decrease in the first cracking load. Based on the findings of this study, high-strength steel fibre reinforced concrete jackets may be considered as a promising material for maintenance and rehabilitation of concrete structures.