Sensitivity of deflection models for FRP-reinforced concrete beams

Abstract

ACI 440.1R-06 and CEB-FIP MC-90 have been used as representative codes in the world for computing deflections of FRP reinforced concrete beams. These codes are based on the equations for an empirically derived effective moment of inertia, indicating the extent of tension stiffening. Deflection behavior of FRP-reinforced concrete beams is not always predicted well using the effective moment of inertia proposed by ACI 440.1R-06 and CEB-FIP MC-90 because their empirical relationship does not reflect the tension stiffening effect, which is highly sensitive to the applied load level relative to the cracking load, the reinforcement ratio, the type of FRP bars, the shape of member section and so on. The purpose of this study is to critically review the equation for effective moment of inertia proposed by the existing codes. A parametric study is carried out to find out the effect of the level of load, the reinforcement ratio, the type of FRP bars and the shape of member section. © 2012 Springer-Verlag Berlin Heidelberg.