Size effect on shear strength of glass fiber-reinforced polymer-reinforced concrete continuous beams

The size effect on the shear strength of continuous concrete beams reinforced with glass fiber-reinforced polymer (GFRP) bars is evaluated. Twelve large-scale continuous reinforced concrete beams were constructed and tested to failure. The test variables included effective depth, longitudinal reinforcement ratio, and concrete strength. Test results indicate that continuous beams exhibited similar size effect to simply supported beams when the beams failed in the exterior shear span. On the other hand, beams failed in the interior shear span showed adverse or no size effect on shear strength. In addition, test results were compared to prediction models and design provisions that were developed based on testing FRP-RC simple structures. It was found that the current shear provisions and models could reasonably predict the shear strength of GFRP-RC continuous beams; however, they fail to predict failure location in such beams. Copyright © 2016, American Concrete Institute.