【摘 要】
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In the context of isogeometric analysis (IGA) of shell structures,the popularity of the solid-shell elements benefit from formulation simplicity and full 3D stress state.However some basic questions remain unresolved when using solid-shell element,especia
【机 构】
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School of Science,Jiangnan University,Wuxi 214122,China;AICES-Aachen Institute for Advanced Study in
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In the context of isogeometric analysis (IGA) of shell structures,the popularity of the solid-shell elements benefit from formulation simplicity and full 3D stress state.However some basic questions remain unresolved when using solid-shell element,especially for large deformation cases with patch coupling,which is a common scene in real-life simulations.In this research,after introduction of the solid-shell nonlinear formulation and a fundamental 3D model construction method,we present a non-symmetric variant of the standard Nitsche\'s formulation for multi-patch coupling in association with an empirical formula for its stabilization parameter.An selective and reduced integration scheme is also presented to address the locking syndrome.In addition,the quasi-Newton iteration format is derived as solver,together with a step length control method.The second order derivatives are totally neglected by the adoption of the non-symmetric Nitsche\'s formulation and the quasi-Newton solver.The solid-shell elements are numerically studied by a linear elastic plate example,then we demonstrate the performance of the proposed formulation in large deformation,in terms of result verification,iteration history and continuity of displacement across the coupling interface.
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