Flexural behavior of basalt fiber reinforced concrete beams: Finite element simulation with new constitutive relationships

Concrete reinforced with fibers is widely utilized to attain noticeable durability in structures. Basalt fibers recently manufactured from igneous basalt rocks have been found to be extensively employed in concrete constructions around the world. The aim of this paper is designed to cover a comprehensive plan for examining the behavior of basalt fiber reinforced concrete (BFRC) beams under bending effect using finite element analysis, and introducing new BFRC constitutive relationships or models. Concrete was modelled by plane stress elements reinforced with embedded steel bars. New models for constitutive relationships were proposed to predict the performance of BFRC under tensile and compressive stresses and estimate its modulus of rigidity after cracking. These models were formulated based on the regression analysis of numerous experimental data compiled from the literature. Different constitutive relationships were proposed and devoted to model the strength of BFRC to the uniaxial compressive stresses, its stiffening to the tensile stress and transference of shear force within the cracked BFRC. The outcomes of present finite element simulation were verified via comparing them with the results of previous testing works in terms of the flexural strength, ductility, and cracking form of BFRC beams. This study reveals that the usage of the proposed elastic-plastic compressive behavior model of BFRC with the second quadratic model of its tension stiffening phenomenon shows minimum error (less than 3.0%) in the predicted behavior of BFRC beams.