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In recent years, load-bearing exterior sandwich wall boards have been adopted in civil engineering. The exterior walls of structures are often exposed to low velocity impacts such as stones, tools, and windborne debris, etc. The ultimate loading capacity, deformation, and ductility of sandwich walls are weakened by impact loads. In this study, the sandwich wall boards consisted of glass fiber reinforced plastic (GFRP) face sheets and a web-foam core. The core of wall boards was not the isotropic material. There was no doubt that the mechanical performance was seriously influenced by the impact locations. Therefore, it is necessary to carry out an investigation on the impact and post-impact performance of exterior wall boards. A comprehensive testing program was conducted to evaluate the effects of impact locations and impact energies on the maximum contact load, deflection, and contact time. Meanwhile, the compression after impact (CAI) performance of wall boards were also studied. The results indicated that the impact location significantly affects the performance of wall boards. Compared with an un-damaged wall board, the residual ultimate loading capacity of damaged wall boards reduced seriously, which were not larger than 50% of the designed ultimate loading capacity.

The strike between flying birds and airplanes results in the unacceptable losses of aircraft structures. The normal approach to evaluate the bird impact resistance is the combined full-scale experimental-numerical study. However, the simulation results from the current available bird constitutive models are usually not in good agreement with the experimental data. Establishing a reasonable bird constitutive model is difficult and significant to the simulation of the bird striking process. In this paper, based on the displacement measurements of an aluminum plate subjected to soft body impact, an inversion of the bird constitutive model is conducted by using backpropagation (BP) neural network. A comparative evaluation of this inversion model and other constitutive models is carried out, indicating that the proposed inversion model is more reasonable.