Strain Rate Effects in Ballistic Analyses of Bonded & Co-Cured Composite Structures

A program is proposed that will extend (and build upon) the work already started by the Survivability Group of the Composites Affordability Initiative, Pervasive Team in developing methods for analyzing the effects of ballistic and hydrodynamic ram (HRAM)loading and damage in bonded/co-cured composite structures.Specifically, the objective will be to remedy a major shortcoming of current HRAM finite element codes, which are unable to accurately model the details that differentiate one joint design from another. The incorporation of stitching, z-pinning,co-curing, and bonding of the joints leads to different failure modes and paths. This is the area in which most work will be performed - in the proper selection of failure criteria within the joints as well as the entire model. Presently, thestate-of-the-art is to use an elastic-plastic smeared properties technique in modeling the structure and