Punching Shear Strength of GFRP-RC Interior Slab–Column Connections Subjected to Moment Transfer

Abstract

This paper presents the test results of five full-scale reinforced concrete (RC) interior slab–column connections. Each specimen consisted of a 2,800-mm square slab with a thickness of 200 and 300-mm square central column stubs. Four slabs were reinforced with glass fiber–reinforced polymer (GFRP) bars and one reference slab was reinforced with steel bars. The connections were subjected to eccentric load with a moment-to-shear ratio equal to 0.15 m. The test parameters included the type and ratio of the reinforcement and concrete compressive strength. Test results revealed that increasing the GFRP reinforcement ratio or the concrete strength increased the connection capacity and decreased the deformation of the tested slabs. Moreover, the GFRP-RC connection that has similar reinforcement rigidity to the steel-RC one showed comparable capacity and deflection at failure. Test results were compared with different available models and design provisions including the Canadian standard, the American guideline, and the Japanese code. The Canadian standard and the Japanese code predicted the punching capacity of the test slabs with better accuracy compared with the American guideline.