Multimode Response of Panels to Sonic Boom

Abstract

The response of panels with simply supported and fully fixed boundary conditions to normal or traveling shock waves from sonic boom and explosions has been studied both theoretically and experimentally. The theory gives, by means of a Duhamel integral method, a closed-form solution for the displacement and strain time histories for panels subjected to the above loads. It is found that the contribution to the panel displacement of the higher modes is relatively small. However, the panel strain time history is highly dependent upon the contributions of higher modes and the panel strain computed merely from the first mode response can seriously under-estimate the magnitude of the maximum strain. Good agreement is obtained between the experimental and theoretical strain maxima; also the initial part of the strain time history is predicted by the theory with fair accuracy. Since the maximum strain rather than maximum displacement is a better criterion for determining panel failure, the theory developed to predict the strain time history has applications in the design of windows or walls to resist sonic boom or explosive blast.