Effect of Shock Wave Incidence Angle on the Dynamic Splitting Mechanical Properties of GFRP-Reinforced Concrete: Experiment and Numerical Simulation

Reinforced concrete (RC) can resist explosive loads, but the propagation process of explosive shock waves inside concrete is complex. To investigate the effect of shock wave incidence angles on the dynamic splitting mechanical properties of concrete reinforced with glass fiber–reinforced polymer (GFRP-RC), this study was conducted using experimental and numerical simulation methods. First, the dynamic splitting strength, energy characteristics, failure evolution mechanism, and failure mode of GFRP-RC under different shock wave incidence angles (30°, 60°, 90°, 120°, 150°) and impact pressures (0.2–0.4 MPa) were studied using a split Hopkinson bar (SHPB) device and digital image correlation (DIC) technology. Then, a numerical model was established using LS-DYNA software, and its reliability was verified based on the experimental results. Finally, the dynamic splitting mechanical characteristics of specimens with different GFRP reinforcement diameters were studied through numerical simulation. The results indicated that the dynamic splitting strength (from 1.02–2.36 MPa) of the specimen was positively correlated with the impact pressure (from 0.2–0.4 MPa). Compared with the shock wave incidence angles of 30°, 60°, 120°, and 150°, the splitting strength and dissipated energy rate on the specimen were the highest when the shock wave incidence angle was 90°. In addition, the stress distribution of the specimen showed symmetry, and the peak stress was a logarithmic function of the GFRP reinforcement diameter. From the analysis of failure modes, the initial cracking position and degree of the specimen’s splitting failure were affected by the shock wave incidence angle. This research result can provide a reference for improving the splitting strength of concrete under impact.