Basic Theory of Steel Fiber Reinforced Concrete

Steel fiber in concrete mainly restricts the expansion of concrete cracks, so that its tensile, flexural and shear strength are significantly improved compared with ordinary concrete. Its impact resistance, fatigue resistance, post-cracking toughness and durability are also greatly improved. It can make the concrete that was originally a brittle material into a composite material with certain plastic properties. Ⅰ . The fiber spacing theory of metal fiber concrete The fiber spacing theory, also known as the fiber crack resistance theory, was proposed by J.P.Romualdi and J.B.Batson in 1963. According to the theory of linear elastic fracture mechanics, the theory explains the restraint effect of fibers on the occurrence and development of cracks. It is believed that in order to increase the tensile strength of concrete, a brittle material with internal defects, it is necessary to reduce the size of internal defects as much as possible and improve toughness. Reduce the...