Effective Moment of Inertia for Glass Fiber-Reinforced Polymer-Reinforced Concrete Beams

TLDR: In this paper, the authors investigated the deflection behavior of concrete flexural members reinforced with glass fiber-reinforced polymer (GFRP) reinforcing bars and found that the ACI 440.1R model overestimates the effective moment of inertia and an appropriate modification is presented.

Abstract: This paper investigates deflection behavior of concrete flexural members reinforced with glass fiber-reinforced polymer (GFRP) reinforcing bars. It is recognized that serviceability plays a major role in the design of GFRP-reinforced concrete beams. Therefore, accurate modeling of flexural stiffness is critical and the effect of influencing parameters must be considered. This study accounts for variations in concrete strength, reinforcement density, and shear span-depth ratio. Experimental results from 48 simply supported concrete beams reinforced with GFRP are compared with ACI Committee 440's published deflection model. The ACI 440.1R model is found to overestimate the effective moment of inertia, and an appropriate modification is presented.