Shear strengthening of RC beams with externally bonded UHPFRC laminates

One of the most frequent and catastrophic problems encountered in reinforced concrete (RC) structures is failure due to shear deficiency in RC structures, especially in RC beams. Thus, in the scope of this experimental study, the effectiveness of using prefabricated ultra-high performance fiber-reinforced concrete (UHPFRC) laminates in the form of plate or strip for shear strengthening was investigated. The change in the plate thicknesses is the first variable of the test program studied herein. Besides, two different application methods were also tested to ensure which can be preferred for shear strengthening with UHPFRC plates; bonding with epoxy, and the use of anchorages. Moreover, as an innovative method, the application of UHPFRC in the form of strip was also investigated. Test results showed that by using UHPFRC laminate as a shear strengthening material; shear strength can be increased by 26% to 47%. Moreover, it is possible to convert behavior from catastrophic shear failure to flexural behavior with the help of UHPFRC laminates. It has been determined that the use of UHPFRC in the strip form helps to increase the load-bearing capacity the most, while the use of anchorage as the bonding method of plates improves the behavior markedly.