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dc.contributor.advisorRaúl A. Radovitzky.en_US
dc.contributor.authorTalamini, Brandon Louisen_US
dc.contributor.otherMassachusetts Institute of Technology. Department of Aeronautics and Astronautics.en_US
dc.date.accessioned2016-07-01T18:22:23Z
dc.date.available2016-07-01T18:22:23Z
dc.date.copyright2015en_US
dc.date.issued2015en_US
dc.identifier.urihttp://hdl.handle.net/1721.1/103420
dc.descriptionThesis: Ph. D., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2015.en_US
dc.descriptionThis electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.en_US
dc.descriptionCataloged from student-submitted PDF version of thesis.en_US
dc.descriptionIncludes bibliographical references (pages 207-221).en_US
dc.description.abstractAlthough advances in computing have increased the limits of three-dimensional computational solid mechanics, structural elements remain essential in the practical design of very large thin structures such as aircraft fuselages, ship hulls, automobiles, submarines, and pressure vessels. In many applications, fracture is a critical design concern, and thus the ability to numerically predict crack propagation in shells is a highly desirable goal. There are relatively few tools devoted to computational shell fracture, and of the existing approaches, there are two main defects: First, the existing methods are not scalable, in the sense of parallel computing, and consequently simulation of large structures remains out of reach. Second, while the existing approaches treat in-plane tensile failure, fracture due to transverse shearing has largely been ignored. In this thesis, a new computational framework for simulating deformation and fracture in large shell structures is presented that is well-suited to parallel computation. The scalability of the framework derives from the combination of a discontinuous Galerkin (DG) finite element method with an interface element-based cohesive zone representation of fracture. This representation of fracture permits arbitrary crack propagation, branching, and merging, without on-the-fly mesh topological changes. Furthermore, in parallel computing, this propagation algorithm is indifferent to processor boundaries. The adoption of a shear-flexible shell theory is identified as a necessary condition for modeling transverse shear failure, and the proposed method is formulated accordingly. Locking is always an issue that emerges in numerical analysis of shear-flexible shells; here, the inherent flexibility afforded by DG methods in the choice of approximation spaces is exploited to prevent locking naturally, without recourse to mixed methods or reduced integration. Hence, the DG discretization elegantly solves both the problems of scalability and locking simultaneously. A stress resultant-based cohesive zone theory is proposed that considers transverse shear, as well as bending and in-plane membrane forces. The theory is quite general, and the specification of particular constitutive relations, in the form of resultant traction-separation laws, is independent of the discretization scheme. Thus, the proposed framework should be extensible and useful for a variety of applications. A detailed description of the implementation strategy is provided, and numerical examples are presented which demonstrate the ability of the framework to capture all of the relevant modes of fracture in thin bodies. Finally, a numerical example of explosive decompression in a commercial airliner is shown as evidence that the proposed framework can successfully perform shell fracture simulations of unprecedented size.en_US
dc.description.statementofresponsibilityby Brandon Louis Talamini.en_US
dc.format.extent221 pagesen_US
dc.language.isoengen_US
dc.publisherMassachusetts Institute of Technologyen_US
dc.rightsM.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.en_US
dc.rights.urihttp://dspace.mit.edu/handle/1721.1/7582en_US
dc.subjectAeronautics and Astronautics.en_US
dc.titleSimulation of deformation and fracture in very large shell structuresen_US
dc.typeThesisen_US
dc.description.degreePh. D.en_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Aeronautics and Astronautics.en_US
dc.identifier.oclc952095390en_US


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