Experimental study and numerical simulation of explosion resistance of GFRP reinforced concrete beams

Abstract

Glass fiber reinforced polymer (GFRP) bars have the advantages of corrosion resistance and high tensile bearing capacity. It can be used as longitudinal reinforcement of concrete protective structures instead of steel reinforcement. In order to clarify the anti-explosion performance of GFRP reinforced concrete beam (GRCBs), the explosion experiment, static bending experiment and numerical simulation analysis of GFRP reinforced concrete beam and reinforced concrete beam (SRCBs) are carried out. The results show that, in the four-point bending static experiment, the bearing capacity of GRCBs designed with the same equivalent stiffness is 5.5 times that of SRCBs under the working condition of 3kg-0.65m explosion loading. With the action of near explosion (proportional detonation distance is less than 0.5159 m kg–3), because the GFRP bars are in the elastic stage, the failure forms are mainly crack, flake and collapse of concrete. According to numerical simulation, the increase of the stiffness of FRP bars can reduce the mid-span displacement of GRCBs. The ratio of the maximum mid-span displacement reduction rate to EA ratio is 0.1, which can reduce the crack and damage of GRCBs and enhance the anti-explosion performance of GRCBs. When the proportional detonation distance is less than 0.4095 m kg–3, C50 and above concrete used in GFRP reinforced concrete beams can effectively reduce concrete collapse and spall. The results show that GRCBs have higher blast resistance than SRCBs.