Projectile penetration into corundum rubble ultra‐high performance concrete: Test and meso‐scale simulation

Abstract Aiming to systematically explore the penetration resistance of corundum rubble ultra‐high performance concrete (CR‐UHPC) with varying oblique and attack angles of projectile, firstly, the laboratory‐based penetration tests (175 m/s) of a 105 mm caliber projectile on CR‐UHPC and normal strength concrete (NSC) targets were conducted using a self‐developed large‐caliber compressed air gun system. The impact resistance of the two types of targets was quantitatively compared, and the feasibility of an indoor penetration test of a large‐caliber projectile was verified. Then, a 3D meso‐scale finite element model of the CR‐UHPC target, considering the random spatial distribution and particle size of corundum rubble, was established to characterize its heterogeneity. The reliability of the corresponding numerical simulation analysis method, including the “take‐place” modeling method, material constitutive models and parameters, mesh sizes, failure criteria values, as well as contact algorithm were fully verified by comparing the predicted depth of penetration (DOP) and projectile profile with the existing 25.3 mm‐caliber penetration test on UHPC target with corundum coarse aggregate and the present conducted test. Finally, the validated numerical simulation analysis method was employed to quantitatively evaluate the penetration resistance of CR‐UHPC and traditional NSC targets under penetration of prototype warhead, that is, Small Diameter Bomb (SDB), with various oblique (0°, 10°, and 20°) and attack (0°, ±1°, and ±2°) angles, and the variations of DOP and deflection angle of projectile were analyzed. The results indicate that: (i) under the sonic‐airspeed (340 m/s) impact of SDB, the DOP in the CR‐UHPC target is only 30% of that in the NSC target; (ii) increasing the oblique angle significantly affected the DOP and projectile deflection angle. When the oblique angle increased from 0° to 20°, the DOP of CR‐UHPC and NSC targets decreased by 11.8% and 14.9%, respectively, while the oblique angle increment increased by 14.97° and 18.40°; (iii) the attack angle mainly affected the projectile deflection angle with a slight effect on DOP. When the attack angle varied from −2° to 2°, the oblique angle increment for CR‐UHPC and NSC targets decreased by 95.9% and 49.1%, respectively, and the DOP variation was within 5% in all scenarios.