Performance of Double-T Prestressed Concrete Beams Strengthened with Steel Reinforced Polymer

In the fall of 2002, a two-storey parking garage in Bloomington, Indiana, built with precast prestrestressed concrete (PC) double-T beams, was decommissioned due to a need for increased parking-space. This led to the opportunity of investigating the flexural performance of the PC double-T beams, upgraded in the positive moment region with steel reinforced polymer (SRP) composite materials, representing the first case study where this material has been applied in the field. SRP makes use of high- strength steel cords embedded in an epoxy resin. This paper reports on the test results to failure of three beams: a control specimen, a beam strengthened with one ply of SRP and a third beam strengthened with two plies of SRP anchored at both ends with SRP U-wraps. Results showed that SRP can significantly improve both flexural capacity and enhance pseudo-ductility. Preliminary analytical work shows that the same approach used for externally bonded fiber reinforced polymer (FRP) can be satisfactorly used for SRP.