The investigation of oblique projectile impacts on concrete structures has become increasingly significant, particularly in the contexts of defense and critical infrastructure. Although extensive research previously has been conducted on the normal impact response of concrete panels, studies focusing on oblique impacts remain limited, despite their relevance in practical scenarios. This study examined the effects of angular/oblique impacts of hard projectiles on plain concrete (PC) and reinforced concrete (RC) panels. An innovative experimental setup was established to examine the oblique impacts on these concrete panels. Twelve specimens, comprising six PC and six RC specimens, were exposed to projectile impacts at three varying incidence angles: 0°, 30°, and 60° relative to the normal of the panel face. Two specimens were tested at each angle, and crucial parameters such as depth of penetration (DOP), crater damage, reaction force, acceleration, and strain were measured to evaluate the panels’ performance under different angular impacts. The findings indicated a decrease in penetration and reaction force with increasing incidence angle, although a slight increase in crater damage was noted. Furthermore, a numerical model using Abaqus was employed to ascertain the true critical incidence angle of 40°, which resulted in the maximum crater damage for this scenario. Ultimately, the experimental data concerning crater damage and DOP were compared with existing probabilistic formulae accounting for the influence of incidence angle on damage parameters. Importantly, the design and protection of concrete structures against oblique impacts should consider not only penetration but also crater damage.
Dar et al. (Wed,) studied this question.