Experimental study on scabbing limit of local damage to reinforced concrete panels subjected to oblique impact by projectile with semispherical nose

Abstract

The influence evaluation against projectile impacts has attracted much attention for the safety assessment of nuclear-facility buildings subjected to projectiles, such as tornado missiles or aircraft. Many experimental studies have been reported on the impact resistance of reinforced concrete (RC) structures. Based on these results, many empirical formulas for penetration depth, scabbing limit thickness, and perforation-limit thickness have been proposed for the local damage evaluation. However, most formulas were derived from impact tests based on normal impact to target structures using rigid projectiles that do not deform during impact. Therefore, this study develops a local damage evaluation method considering the rigidity of projectiles and oblique impacts that should be considered in realistic projectile impact phenomena. Specifically, we focused on scabbing, defined as the peeling off the back face of the target opposite the impact face, and conducted impact tests on RC panels to clarify the scabbing limit by changing the impact velocity in an oblique impact. The effects of the projectile rigidity and oblique impact on the scabbing limit were investigated based on the test results. This work presents the test conditions, equipment, results, and the scabbing limit on the local damage to RC panels subjected to oblique impacts.

Keywords

• reinforced concrete panel
• oblique impact
• impact test
• local damage
• soft projectile