Inclined projectile impact on reinforced concrete structures

• Numerical simulations with LS-DYNA capable to reproduce experimental tests. • Validation of two selected friction models for inclined impact scenarios. • Adjustment of Riera’s critical angle for estimating support forces. • Parametric study on residual velocities based on varying impact angles. Impact loads, such as airplane or debris crashes, are a significant load case in the safety assessment and design of nuclear facilities. In the past, research on impact events primarily focused on impact scenarios with normal angle. However, in real-world situations, an inclined angle of impact can be expected for impact events. As a result, there is a growing need to investigate the effects of inclined impact on reinforced concrete structures with a focus on the resulting damage and failure modes. Understanding the effects of impact angles on the load-bearing capacity of these structures is crucial for ensuring their safety and integrity. This paper examines the effects of inclined projectile impacts on the load-bearing capacity of reinforced concrete structures for both soft and hard missiles. Nonlinear dynamic numerical simulations using 3D fully coupled analysis are conducted and validated against experimental test results from the literature. Different friction models are implemented and evaluated for punching and bending responses. The friction models examined in this paper show strong agreement with experimental data, confirming their reliability in simulating both punching and bending tests. In addition to the numerical analyses, simplified approaches for calculating the support forces as well as residual velocities for different impact angles are investigated and validated with experimental data and simulations, showing reasonable agreement with both numerical models and experimental data.