Closed-form moment-curvature expressions for homogenized fiber-reinforced concrete

A closed form solution is presented for the moment-curvature response of cement-based composites with homogeneously distributed reinforcement. The derivation is based on parametric representation of uniaxial material constitutive response using pi. ece-wise linear and quadratic. segments. Effects of tensile and compressive constitutive relations on moment-curvature response were studied and it was observed that the tensile stiffness from the first cracking to the ultimate tensile strength. and the ultimate tensile strain were the most important parameters. The moment-curvature relation was combined with crack localization rules to simulate the flexural load-deformation response of a beam under four-point loading conditions. Model simulations indicate that the direct use of uniaxial tension stress-strain response underpredicts the flexural results. This is attributed to the differences in the effective volume of the material subjected to critical stress. By applying a single scaling factor to material models, the model simulations can match the experimental data.