UHP-SFRC panels subjected to aircraft engine impact: Experiment and numerical simulation

Investigations of the large commercial aircraft impact effect have been drawing extensive attention, and the detached massive engine during aircraft collision would cause severer local damage to structures than the aircraft fuselage. Ultra high performance steel fiber reinforced concrete (UHP-SFRC) is an excellent material for the construction of valuable infrastructures to resist the intensive loadings. This paper aims to study the impact resistance of UHP-SFRC panels subjected to the aircraft engine. Firstly, a series of reduce-scaled engine model perforation test was conducted, in which the residual velocities of the engine missiles as well as the damage of both engine missile and target slab were derived and assessed. Then, a mesoscopic model of UHP-SFRC considering the random distribution, volumetric ratio, as well as the bonding and slipping effects of the fibers was established. By using the finite element program LS-DYNA and comparing with the macroscopic homogenous approach, the present test was better reproduced by the mesoscopic approach. Furthermore, based on the parametric analyses of panel thickness and engine missile impact velocity, a modified empirical formula for predicting the engine missile residual velocity was presented to guide the design of protective structures.