Blast and Ballistic Response of Advanced Composite Structures

KCI will develop a dynamic, nonlinear FEA methodology for evaluation and/or optimization of marine composite structures subjected to conventional weapon external and internal blast and ballistic threats. LS-DYNA3D will be extended via user defined materialmodels. Phase I will concentrate on sandwich panel structures, stiffened sandwich panels, and joining sandwich panels. The KCI team has years of experience in design, optimization, and construction of stiffened composite sandwich panel structures for usein blast-hardened military C3I shelters.Important aspects of the analysis methodology are the elements and material models used for accurately and efficiently representing deformation and damage in composite face sheets, core, and structural connections. Practical models used must employparameters whose values are readily available or easily measured. A test program for supplying these parameters will be proposed. Initial development of FEA methodology will use prototypical blast and impact validation problems, designed to exhibitsignificant damage modes, such as face sheet tensile, compressive, or wrinkling failures, core shear/compression failure, delamination, panel buckling, and failure of structural connections. A set of guidelines for accurate and efficient analysis of marinecomposite sandwich structures will be developed. Key to this effort is an understanding of the needs of the designer. In addition to serving the specific needs expressed in the solicitation, KCI anticipates that the developed finite element analysis methodology will be applicable to the design and optimization of a wide variety of other military and civilian systems.For example, terrorist threats have provided motivation to evaluate new and existing structures for their ability to withstand blast and/or ballistic impact loading. The modeling methods developed and demonstrated in the proposed software development anddemonstration will allow designers to more accurately and efficiently capture the failure mechanisms that are unique to composite sandwich structure.