EXPERIMENTAL INVESTIGATION ON THE FRACTURE ENERGY OF FIBER REINFORCED SELF-COMPACTING CONCRETE
On the base of three-point bending experiments of a total of 56 specimens in 14 groups,the influencing rules of steel fiber,polyacrylonitrile(PAN) fiber,and hybrid steel/PAN(S/P) fiber on the fracture energy of self-compacting concrete(SCC) are investigated in this paper.The relative SCC specimens without any fiber were tested and compared with the fiber reinforced SCC to accumulate the increment ratio of fracture energy.The results show that the fracture energy of SCC increases obvious linearly with the increment of steel fiber.PAN fiber tends to be nonlinearly improves the fracture energy of SCC,but not so obviously as steel fiber.As to hybrid S/P fiber reinforced SCC having a constant content of steel fiber,the fracture energy increases nonlinearly with the increment of PAN fiber.On the base of experimental results,a calculation model of fiber reinforced SCC is presented with compressing strength,maximum size of aggregate and influencing coefficient as main factors.The calculating results of suggested model are compared with experimental results and excellent agreement is found