Bombardment analysis method for assessing truss system combat survivability

Abstract

The system combat surviv ability of structures is an essential issue of design analysis for many important structures such as the truss boom of an attack helicopter. Its system failure due to combat damage may cost much more than the repairable nonsystem failure. Nevertheless, before the difficult system survivability of twodimensional multiple-story and statically indeterminate truss structures can be assessed, the bombardment survivability of each truss component should be predicted somehow. In this article, the Poisson process is used to model the approaching situation of fragments from a high explosive warload detonated in the vicinity of the targeted area encompassing a truss structure. Then a judicious Lee-Buffon method is developed and merged with the Poisson's model to accommodate the bombardment analysis of truss components due to small incoming fragments in a decomposed and probabilistic sense. Moreover, the ingenious combinational pivotal decomposition method is employed to assess the truss system combat survivability systematically. With minor modification, this analysis scheme may also be applied for space station truss structures subject to micrometeoroid/debris impacts.