Research on mode-I fracture characteristics of basalt fiber reactive powder concrete

Abstract

Basalt fiber reactive powder concrete (BFRPC) has strong potential application value because of its green environmental protection and good comprehensive properties. However, basalt fiber content is the important factor affecting the mode-I fracture characteristics of reactive powder concrete (RPC). Through the three-point bending fracture experiments, the effect of different basalt fiber content (0 %∼2.0 %) on the fracture parameters of RPC was studied. Based on DIC technology, the crack propagation and fracture process zone (FPZ) evolution of BFRPC were deeply studied, and the deformation and failure ability of BFRPC was evaluated by horizontal displacement standard deviation. The results showed that the double-K fracture toughness of RPC reaches the maximum (0.71 and 1.78 MPa mm1/2) under the action of 1.5 % basalt fiber content. However, the interfacial fracture energy is positively correlated with the basalt fiber content. Due to the bridging and restraint effect of basalt fiber on RPC, an appropriate amount of basalt fiber (0.5%–1.5 %) can effectively reduce the length of FPZ. The basalt fiber content has a positive effect on the growth of horizontal displacement standard deviation of BFRPC, which further highlights the excellent ability of BFRPC to resist deformation and failure.