In order to further analyze the fracture mechanism of steel fiber reinforced concrete and assess its fracture resistance,the three-point bending fracture test was carried out to analyze the fracture properties of steel fiber rein-forced concrete with different fiber lengths and different fiber parameters.The loading point displacement,crack mouth opening displacement and crack opening displacement along the ligament were observed by digital image correlation method.The fracture energy,initial fracture toughness and unstable fracture toughness of steel fiber reinforced concrete were calculated.The results show that the fracture energy increases approximately linearly with the increase of steel fi-ber length.With the increase of steel fiber volume content,the fracture energy firstly increases and then decreases,and when the fiber volume content is 1.0%,the fracture energy reaches the maximum value.By adding the steel fi-ber,the initial fracture toughness of concrete improved slightly,whereas the unstable fracture toughness of concrete is also significantly increased.
维普
万方数据