Resistance of high-strength concrete to projectile impact

This paper presents the results of an experimental study on the impact resistance of concrete with compressive strengths of 45-235 MPa when subjected to impact by 12.6 mm ogive-nosed projectile at velocities ranging from ∼620 to 700 m/s. The results indicate that the penetration depth and crater diameter in target specimens exhibit an overall reduction with an increase in the compressive strength of the concrete. However, the trend is not linear. Further increase in the compressive strength requires a reduction in the water-to-cementitious material ratio and the elimination of coarse aggregates. However, doing these does not result in reduction of the penetration depth and crater diameter. The presence of coarse granite aggregates appears to be beneficial in terms of reducing penetration depth, crater diameter, and crack propagation, thus contributing to impact resistance. Incorporation of steel fibers in the concrete reduced the crater diameter and crack propagation, but did not have a significant effect on penetration depth. An increase in the curing temperature from 30°C to 250°C did not alter the impact resistance of the concrete significantly. Based on the present findings and cost consideration, high-strength fiber-reinforced concrete with a compressive strength of ∼100 MPa appears to be most efficient in protection against projectile impact.