Abstract
The purpose of this study is to determine the tension softening diagram and post-crack tensile strength of polypropylene fiber-reinforced lightweight concrete from bending tests and pull-out tests. Lightweight concrete has been actively applied in civil engineering applications, because the lightweight concrete is effective to reduce the dead load of structures and to improve the earthquake response of substructures. The addition of discontinuous fibers to cementitious materials drastically extends the toughness and strength of concrete. The tension softening diagram and fracture energy are important factors to analyze the mechanical behavior of concrete structures. And also, the post-crack tensile strength has been applied to predict the shear strength of fiber-reinforced concrete beams. In this study, the tension softening diagram and post-crack tensile strength of polypropylene fiber-reinforced lightweight concrete was determined by the bending test and the method based on the poly-linear approximation analysis. Furthermore, the post-crack tensile strength was clarified by the fiber-matrix interfacial bond strength obtained from the pull-out test.
