The solid-shell elements have shown great advantages in three-dimensional (3D) finite element (FE) simulation of thin-walled structures. To overcome the numerical lockings for 3D element with a large span-thickness ra...
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The solid-shell elements have shown great advantages in three-dimensional (3D) finite element (FE) simulation of thin-walled structures. To overcome the numerical lockings for 3D element with a large span-thickness ratio, the assumed natural strain (ANS) method combined by either the hybrid stress (HS) or enhanced assumed strain (EAS) formulations are commonly used. In this work, two types of finite element formulations of the solid-shell elements are developed for nonlinear thermoelastic analysis of thin-walled structures, which are termed as the "ANS+HS"and "ANS+EAS"formulations. Accordingly, two eight-node solid-shell elements (CSSH8 and CSSE8) are developed based on the "ANS+HS"and "ANS+EAS"formulations, respectively. The Green-Lagrange displacement-strain relation is applied to involve the geometrical nonlinearities, and both the thermal expansion and temperature-dependent material properties are considered. nonlinearthermoelastic equilibrium equations are constructed in the framework of the two types of finite element formulations using the Hellinger-Reissner and conventional variational principles, respectively. The proposed method can easily realize three different coupling analyses for thermal-mechanical loads by modifying the parameters of nonlinearthermoelastic equilibrium equations. Numerical examples demonstrate that the proposed method using CSSH8 and CSSE8 elements traces the nonlinearthermoelastic response of the isogrid stiffened panel as accurately as the shell, solid-shell, and solid elements of ABAQUS. Furthermore, the path-following capability of the proposed method using the CSSH8 with "ANS+HS"formulation is slightly superior to that using the CSSE8 with "ANS+EAS"formulation, but both better than ABAQUS.
A pre-correction multiscale strategy is developed for the nonlinear thermoelastic analysis of heterogeneous multiphase materials with temperature-dependent properties. In this strategy, based on the multiscale finite ...
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A pre-correction multiscale strategy is developed for the nonlinear thermoelastic analysis of heterogeneous multiphase materials with temperature-dependent properties. In this strategy, based on the multiscale finite element formulation, the numerical base functions (NBFs) are constructed in order to bring the microscopic heterogeneous properties to the macroscopic response. By constructing the microscopic perturbed pre-correction the inaccuracy of the NBFs due to the temperature-dependent properties is better considered, as well as the influence of the microscopic loads. Then the pre-correction multiscale strategy is implemented for the nonlinear heat conduction and thermoelasticanalysis. Finally several representative numerical examples are presented and the results indicate that the proposed strategy is efficient and accurate for modeling heterogeneous multiphase materials. (C) 2014 Elsevier B.V. All rights reserved.
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