Abstract
Serviceability limit states require that cracking of reinforced concrete members be controlled for appearance, leaking, and durability requirements. The calculation of crack width in glass fiber–reinforced polymer (GFRP)-reinforced concrete flexural members is dependent on many factors, such as concrete cover, bar spacing, bar tensile stress, and bond-dependent coefficient (kb), which accounts for the bar surface condition. This article presents the determination of the bond-dependent coefficient (kb) for helically wrapped sand-coated deformed GFRP bars. A total of six beams were fabricated and tested for three different diameters of GFRP bars: #4 (13 mm), #6 (19 mm), and #8 (25 mm). The calculated values were compared against the proposed values according to ACI 440.1R, Guide for the Design and Construction of Structural Concrete Reinforced with Fiber-Reinforced Polymer Bars, and CAN/CSA S806, Design and Construction of Building Structures with Fibre-Reinforced Polymers. The average kb value of the tested GFRP bars was found to be 1, which indicates similar bond behavior to deformed steel bars. Also, the kb values proposed in ACI 440.1R overestimate crack width, while kb values proposed in CAN/CSA S806 are close to the ones obtained from the tested GFRP bars.