Concrete contribution to shear resistance of GFRP-RC beams under fire exposure

Abstract

Currently, there is a lack of research on how fire affects the shear capacity of reinforced concrete (RC) beams reinforced with glass fiber-reinforced polymer (GLASS-F.R.P.) bars. This study examines the shear performance of beams reinforced with GLASS-F.R.P. bars when exposed to fire. Twelve RC beam specimens were fabricated for this purpose, exposed to fire, and then subjected to four-point bending until failure. The specimens had a total span of 1700 mm and a concrete cross-section measuring 150 mm wide and 300 mm deep. The parameters were the ratio of reinforcements and the duration of the firing. The test findings indicate that the concrete's ability to resist shear forces is affected by both the ratio of reinforcement and the length of time it is exposed to fire. Increasing the amount of flexural reinforcement specifically enhances the shear capability. On the other hand, increasing the amount of time that something is subjected to fire decreases its ability to withstand force. It has been noted that the shear design equations from ACI 440.11–22 (ACI-22) and ECP 208–05 (ECP-05) tend to be conservative for elements regardless of fire exposure. In contrast, the shear design methodology described in CSA S806–12 (CSA-12) stands out as the most accurate approach for predicting shear capacity.

Keywords

• Fire
• Reinforcement ratio
• Beams
• GLASS-F.R.P. bars
• F.R.P. codes
• Shear strength