H-Adaptive Updated Lagrangian Approach for Large-Deformation Analysis of Slope Failure

An incremental constitutive relation of friction contact is presented for large deformation analysis. After a brief review of published explanations of friction, a model is constructed following the established concepts of plasticity theory. Extensive studies are laid on how the theory closely simulates the nature of friction and how the unknown parameters in the equation are to be determined from the existing experimental results. Possible extensions to allow considerations of temperature and nonlocal effects are discussed. Formulations of a quasistatic boundary value problem based on the updated Lagrangian approach are summarized. The elastoplastic material is assumed to behave according to the generalized Prandtl-Reuss constitutive equation. Finite element methods are employed to solve the problem. Two examples are selected to demonstrate the capability and adequacy of the proposed model.

Download Full-text

An Adaptive Local Meshfree Updated Lagrangian Approach for Large Deformation Analysis of Metal Forming

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.2664 ◽

2010 ◽

Vol 97-101 ◽

pp. 2664-2667 ◽

Cited By ~ 1

Author(s):

Yuan Tong Gu

Keyword(s):

Large Deformation ◽

Metal Forming ◽

Meshfree Methods ◽

Superior Performance ◽

Deformation Analysis ◽

Large Deformation Analysis ◽

Good Potential ◽

Updated Lagrangian Approach ◽

Updated Lagrangian ◽

Large Deformation Problems

The large deformation analysis is one of major challenges in numerical modelling and simulation of metal forming. Because no mesh is used, the meshfree methods show good potential for the large deformation analysis. In this paper, a local meshfree formulation, based on the local weak-forms and the updated Lagrangian (UL) approach, is developed for the large deformation analysis. To fully employ the advantages of meshfree methods, a simple and effective adaptive technique is proposed, and this procedure is much easier than the re-meshing in FEM. Numerical examples of large deformation analysis are presented to demonstrate the effectiveness of the newly developed nonlinear meshfree approach. It has been found that the developed meshfree technique provides a superior performance to the conventional FEM in dealing with large deformation problems for metal forming.

Download Full-text

Meshless TL and UL Approaches for Large Deformation Analysis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.139-141.893 ◽

2010 ◽

Vol 139-141 ◽

pp. 893-896 ◽

Cited By ~ 4

Author(s):

Yuan Tong Gu

Keyword(s):

Large Deformation ◽

Computational Efficiency ◽

Metal Forming ◽

Weak Form ◽

Superior Performance ◽

Deformation Analysis ◽

Large Deformation Analysis ◽

Updated Lagrangian ◽

Local Weak Form ◽

Large Deformation Problems

To accurately and effectively simulate large deformation is one of the major challenges in numerical modeling of metal forming. In this paper, an adaptive local meshless formulation based on the meshless shape functions and the local weak-form is developed for the large deformation analysis. Total Lagrangian (TL) and the Updated Lagrangian (UL) approaches are used and thoroughly compared each other in computational efficiency and accuracy. It has been found that the developed meshless technique provides a superior performance to the conventional FEM in dealing with large deformation problems for metal forming. In addition, the TL has better computational efficiency than the UL. However, the adaptive analysis is much more efficient using in the UL approach than using in the TL approach.

Download Full-text