Tension Stiffening and Cracking Behavior of Glass Fiber-Reinforced Polymer-Reinforced Concrete

摘要

In this study, 60 large-scale specimens—52 glass fiber-reinforced polymer (GFRP) reinforced concrete and eight steel-reinforced concrete—were tested under uniaxial tension to investigate tension stiffening and cracking behavior of GFRP-reinforced normal- and high-strength concretes. The test parameters included bar type, bar diameter, reinforcement ratio, and concrete strength. Tension stiffening was found to be independent of concrete strength, bar diameter, and reinforcement ratio when shrinkage was included in the analysis of the member response. The final stabilized crack spacing was found to decrease with an increase in reinforcement ratio and concrete strength, and a decrease of bar diameter. The current code provisions and guidelines—namely, ACI 440.1R-06 and CEB-FIP Model Code 2010—were found to significantly overestimate tension stiffening in GFRP-reinforced specimens. A new tension stiffening model was therefore developed that provided better simulation of the test data. The CEB-FIP 1978 model for crack spacing was modified for GFRP-reinforced members.