• Transactions of Materials Processing
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• v.12 no.3
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• pp.194-201
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• 2003

An automatic quadrilateral mesh generator for large deformation finite element analysis such as metal forming simulation was developed. The NURBS interpolation method is used for modeling arbitrary 2-D free surface. This mesh generation technique is the modified paving algorithm, which is an advancing front technique with element-by-element resolving method for paving boundary intersection problem. The mesh density for higher analysis accuracy and less analysis time can be easily controlled with high-density points, maximum and minimum element size. A couple of application to large deformation finite element analysis is given as an example, which shows versatility and applicability of the proposed approach and the developed mesh generator for large deformation finite element analysis.

• Journal of Hydrospace Technology
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• v.1 no.1
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• pp.111-124
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• 1995

An improved analysis model for material nonlinearity induced by elasto-plastic deformation and damage including a large strain response was proposed. The elasto-plastic-damage constitutive model based on the continuum damage mechanics approach was adopted to overcome limitations of the conventional plastic analysis theory. It can manage the anisotropic tonsorial damage evolved during the time-independent plastic deformation process of materials. Updated Lagrangian finite element formulation for elasto-plastic damage coupling problems including large deformation, large rotation and large strain problems was completed to develop a numerical model which can predict all kinds of structural nonlinearities and damage rationally. Finally a finite element analysis code for two-dimensional plane problems was developed and the applicability and validity of the numerical model was investigated through some numerical examples. Calculations showed reasonable results in both geometrical nonlinear problems due to large deformation and material nonlinearity including the damage effect.

• Geomechanics and Engineering
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• v.29 no.6
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• pp.683-696
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• 2022

Dams are inevitably planned to be built on thick overburden with high permeability and deformability. The connection part between concrete cut-off wall in overburden and earth core in dam body is not only a key part of the anti-seepage system, but also a weak position. Large uneven settlement will be aroused at the concoction part. However, the interaction behavior and the scope of the connection part cannot be determined effectively. In this paper, numerical analysis of a high earth core dam built on thick overburden was carried out with large deformation FE method. The mechanical behavior of the connection part was detail studied. It can be drawn that there is little differences in dam integral deformation for different analysis method, but big differences were found at the connection part. The large deformation analysis method can reasonably describe the process that concrete wall penetrates into soil. The high plasticity clay has stronger ability to adapt to large uneven deformation which can reduce stress level, and stress state of concrete wall is also improved. The scope of high plasticity clay zone in the connection part can be determined according to stress level of soils and penetration depth of concrete wall.

• Transactions of Materials Processing
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• v.4 no.1
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• pp.92-104
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• 1995

It often happens some elements are so largely distorted during a large-deformation finite element analysis that further calculation becomes impossible or the approximation error increases rapidly. This problem can be overcomed only by remeshing at several suitable stages. The present study aimed to establish the criterion based on the error estimators, and examined in the simulation and posterior error analysis of ring compression test to demonstrate the usefulness of them. The distribution of each error estimator and its variation during deformation were investigated. All the error estimators were increased monotonously with deformation and decreased rapidly at remeshing stage. It was shown that the error estimators suggested in this study are good measures as remeshing criterion for large deformation finite element analyses.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.225-231
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• 2005

In this paper, to prediction of large deformation behavior of steel structures under loading, 3-Dimensional elastic-plastic FE analysis method is developed by using finite deformation theory and proposed cyclic plasticity model. The accuracy of developed analytical method was verified by comparison of experiment result and analysis results using infinitesimal deformation theory. The good agreement between analysis result by developed analytical method and experiment result is shown. Proposed 3-dimensional FE analysis using finite deformation theory and cyclic plasticity hysteresis model can be predict the large deformation of steel members under cyclic loading.

• Geomechanics and Engineering
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• v.38 no.6
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• pp.583-591
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• 2024

To properly simulate the excavation process and evaluate the structural stability of the tunnel, rigorous large deformation analysis method is necessary. This study applies two most widely used numerical approaches capable of modelling and considering the large deformations behavior during excavation process to analyze and evaluate the structural stability of circular tunnel based on tunnel boring machine (TBM) excavation. By comparing and combining the results from two numerical approaches, the deformation of the excavated ground will be analyzed. The stability of the circular tunnel from TBM tunneling was assessed based on the maximum deformation occurred during the excavation process. From the numerical computation it was concluded that although the range of the damage on the ground done during excavation was found to be larger under hard rock condition, maximum deformation within the circular tunnel structure was larger under weak ground conditions and deeper tunnel depths.

• Journal of Korean Association for Spatial Structures
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• v.6 no.4 s.22
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• pp.53-61
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• 2006

In th is paper, to predicting the large deformation and cyclic plastic behavior of steel members under loading, 3-Dimensional elastic-plastic FE analysis method is developed by using finite deformation theory and proposed cyclic plasticity model. finite deformation theory, described the large deformation, is formulated by using Updated-lagrangian formulation and Green's strain tensor, Jaumann's derivative of Kirchoff stress. Also, cyclic plasticity model proposed by author is applied to developed analysis method. To verification of developed analysis method, analysis result of steel plate specimen compare to the analysis result using infinitesimal deformation theory and test result. Also, load-displacement and deflection shape, analysis result of pipe-section steel column, compare to test result. The good agreement between analysis result and experiment result shown that developed 3-dimensional finite element analysis can be predict the large deformation and cyclic plastic behavior of steel members.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.3
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• pp.47-53
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• 2005

The non-linear finite element program of the large deformation analysis by computer simulation has been used in the prediction and evaluation of the behaviors of the non-linear rubber components. The analysis of rubber components requires the tools modelling the special materials that are quite different from those used for the metallic parts. The nonlinear simulation analysis used in this study is expected to be widely applied in the design analysis and the development of several rubber components which are used In the manufacturing process of many industries. By utilizing this method, the time and cost can also be saved in developing the new rubber product. The objective of this study is to analyze the rubber component with the large deformation and non-linear properties.

• Journal of Welding and Joining
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• v.21 no.1
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• pp.93-98
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• 2003

For construction of steel structures, thin steel plates have been often used and welding is the main manufacturing process. However, welding processes cause some problems(welding residual stresses, welding deformations, etc.). In these problems, welding deformation is extremely harmful to the safety of structures especially. Therefore, in this study, a numerical analysis program based on large deformation plate theory has been developed to analyze and predict the welding deformation in thin plates. From the result of numerical analyse, we can find two parameters, thermal cycles and mechanical restraints affecting the welding deformation of structures. It is considered that large difference of thermal cycles and mechanical restraints in the width direction bring about welding deformation. Results of simulation have the same tendency of deformation distribution in width direction as experimental formulas.

• Journal of the Korean Geotechnical Society
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• v.18 no.4
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• pp.207-214
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• 2002

A constitutive model was implemented in ABAQUS code, The constitutive equation can model the behavior for overall range of strain level from small to large deformation, which is based on anisotropic hardening rule and total stress concept. The formulation includes (1) finite strain formulation on the basis of Jaumann rate, (2) implicit stress integration and (3) consistent tangent moduli. Therefore, the mathematical background was established in order that large deformation analysis can be performed accurately and efficiently with the anisotropic constitutive model. Companion paper(Jeon et al., 2002) will contain the large deformation analysis results of examples with the constitutive model using ABAQUS.