Numerical simulation of impact of aircraft and engine into concrete wall

Abstract

A safety assessment needs to be conducted to analyze the damage caused by an aircraft impacting into a concrete structure at a nuclear power plant. One of the analytical methods used for this issue is a numerical impact simulation conducted after aircraft and reinforced concrete (RC) models are determined. We established the RC model and aircraft model in this study and confirmed the applicability of an impact simulation. Validation of our RC model was confirmed by conducting impact simulations of an F4 Phantom engine (GE-J79) crashing into three different wall thicknesses of 900, 1150, and 1600 mm. The damages to the wall in the simulations agreed with the test results conducted at Sandia National Laboratory around 1990. We also conducted parametric impact simulations of a rigid missile crashing into a concrete wall, changing the impact speed, mass of the missile, and the wall thickness. The wall thickness required to prevent perforation in the simulations was close to that estimated by the empirical formulae, although the residual speeds of the missile after the perforation in simulation did not agree very well to the values obtained by empirical formulae. One of the reasons of the difference in the residual speed is that the speed of the ejected concrete was not considered in our RC model. An impact simulation of an F4 Phantom crashing into a RC wall was conducted for the validation of our aircraft model. The shape of the impact load and the state of the frames of F4 Phantom on impact were almost the same as those in the test results conducted at Sandia, which showed that the F4 Phantom model was valid.

Keywords

• aircraft impact analysis
• impact simulation
• simulation model
• concrete wall
• aircraft engines