Composite Design Methodology: Design of Composite Trails for the U.S. Army’s M198 Howitzer, A Case Study

Analysis and design of a fiber reinforced organic composite trail pair for the U.S. Army M198 Howitzer is presented as a case study in composite material design methodology. For this purpose mechanics analysis is performed using the computer program: MIC-MAC composites design and ANSYS 4.4A finite element analysis. The analyses includes composite lamination, material optimization, adhesive bonding, buckling, deflection, stress and failure analysis and validates the practicability of the proposed constant cross-section graphite/epoxy trail. The use of PC based spreadsheet MIC-MAC program, initially, allows efficient and inexpensive evaluation of several alternative designs including different geometries and materials before the finite element program is employed with the few final design choices to rule out failure in stress, deflection and buckling modes. However, superposition principles need to be used to describe the complex loading configuration as a collection of mechanically equivalent individual load modes such as midspan loaded beam, cantilever beam under torsion, in-plane loaded plate etc. in order to be able to utilize the MIC-MAC program initially. Fabrication plans are also proposed for the trail pair.