

Type of Document Master's Thesis Author Coggin, John Moore Author's Email Address jcoggin@adoptech.com URN etd-03152000-10210026 Title Response of Isotropic and Laminated Plates to Close Proximity Blast Loads Degree Master of Science Department Aerospace and Ocean Engineering Advisory Committee
Advisor Name Title Kapania, Rakesh K. Committee Chair Johnson, Eric R. Committee Co-Chair Nikolaidis, Efstratios Committee Member Keywords
- composite
- contact
- finite element
- nonlinear
- blast load
Date of Defense 2000-02-15 Availability unrestricted Abstract Response of Isotropic and Laminated Plates toClose Proximity Blast Loads
By
John M. Coggin
Rakesh K. Kapania, Chairman
Eric R. Johnson, Co-Chairman
(ABSTRACT)
The transient response of various plate structures subject to blast loads is analyzed. In particular, simply supported isotropic and laminated composite plates are modeled using the commercial finite element code NASTRAN and the method of modal superposition. Both analysis procedures are used to quantify the linear transient response of such plates subject to uniform and patch blast loads. Furthermore, NASTRAN is used to study the nonlinear response of plates subject to close proximity explosions. Also considered here is the case for which a blast loaded plate impacts another closely neighboring plate. The NASTRAN solution used here accounts for nonlinearities due to large plate deflections, plasticity, and plate-to-plate contact.
Many studies are currently available in which the blast load is considered to be spatially uniform across the plate; with a temporal distribution described by step, N-pulse, or Friedlander equations. The novel aspect considered here is the case for which the blast pressure is due to a close proximity explosion, and it is therefore taken to be both spatially and temporally varying. A FORTRAN program is described which automates the application of an arbitrary blast load to a generic finite element mesh. The results presented here are a collection of analyses performed for a variety of parameters important to the dynamic response of blast loaded contacting plates. Conclusions are drawn concerning the influence of the various parameters on the nature of the plate response and the quality of the solution.
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