R.A. Regueiro^1,2, B. Zhang², S.L. Wozniak³

CMES-Computer Modeling in Engineering & Sciences, Vol.98, No.1, pp. 1-39, 2014, DOI:10.3970/cmes.2014.098.001

Abstract The paper presents three-dimensional, large deformation, coupled finite element analysis (FEA) of dynamic loading on soft biological tissues treated as biphasic (solid-fluid) porous media. An overview is presented of the biphasic solidfluid mixture theory at finite strain, including inertia terms. The solid skeleton is modeled as an isotropic, compressible, hyperelastic material. FEA simulations include: (1) compressive uniaxial strain loading on a column of lung parenchyma with either pore air or water fluid, (2) out-of-plane pressure loading on a thin slab of lung parenchyma with either pore air or water fluid, and (3) pressure loading on More >

Zhicheng Ou¹, Xiaohu Yao¹, Xiaoqing Zhang^1,2, Xuejun Fan³

CMC-Computers, Materials & Continua, Vol.44, No.3, pp. 205-222, 2014, DOI:10.3970/cmc.2014.044.205

Abstract The buckling of a thin film on a compressible compliant substrate in large deformation is studied. A finite-deformation theory is developed to model the film and the substrate under different original strain-free configurations. The neo-Hookean constitutive relation is applied to describe the substrate. Through the perturbation analysis, the analytical solution for this highly nonlinear system is obtained. The buckling wave number, amplitude and critical condition are obtained. Comparing with the traditional linear model, the buckling amplitude decreases. The wave number increases and relates to the prestrain. With the increment of Poisson’s ratio of the substrate, More >

V. Filonova¹, Y. Liu¹, M. Bailakanavar¹, J. Fish¹, Z. Yuan²

CMC-Computers, Materials & Continua, Vol.34, No.3, pp. 177-198, 2013, DOI:10.3970/cmc.2013.034.177

Abstract A corotational formulation for reduced order homogenization is presented. While in principle the proposed method is valid for problems with arbitrary large strains, it is computational advantageous over the classical direct computational homogenization method for large rotations but moderate unit cell distortions. We validate the method for several large deformation problems including: (i) hat-section composite beam with two-dimensional chopped tow composite architecture, (ii) polyethylene microstructure consisting of 'hard' and 'soft' domains (segments), and (iii) fiber framework called fiberform either embedded or not in an amorphous matrix. More >

Y.C. Cai¹, S.N. Atluri²

CMES-Computer Modeling in Engineering & Sciences, Vol.83, No.3, pp. 249-274, 2012, DOI:10.3970/cmes.2012.083.249

Abstract This paper presents a very simple finite element method for geometrically nonlinear large rotation analyses of plate/shell structures comprising of thin members. A fully nonlinear theory of deformation is employed in the updated Lagrangian reference frame of each plate element, to account for bending, stretching and torsion of each element. An assumed displacement approach, based on the Discrete Kirchhoff Theory (DKT) over each element, is employed to derive an explicit expression for the (18x18) symmetric tangent stiffness matrix of the plate element in the co-rotational reference frame. The finite rotation of the updated Lagrangian reference… More >

Dongdong Wang, Zhuoya Li, Youcai Wu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 107-108, 2011, DOI:10.3970/icces.2011.017.107

Abstract Meshfree methods have experienced substantially fundamental development and various applications. One distinguished advantage for meshfree methods is that they can relieve the mesh tangling burden of FEM and are more suitable for finite deformation analysis. In this work a three dimensional updated Lagrangian Galerkin meshfree formulation with improved computational efficiency is presented to analyze the failure of soil slopes. This nonlinear meshfree formulation is featured by the Lagrangian stabilized conforming nodal integration method where the low cost nature of nodal integration approach is kept and at the same time the numerical stability is obtained as… More >

Xiaohua Tan, Yilan kang^*, Ganyun Huang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.1, pp. 31-32, 2011, DOI:10.3970/icces.2011.017.031

Abstract Soft materials are a special class of materials between the ideal fluid and solid (Gennes, 1992), comprising a variety of physical states that are easily deformed by mechanical loading or thermal fluctuations. They are increasingly important in a wide range of technological applications, and the related contact problem is rather complex due to geometrical and material nonlinearities and complicated boundary conditions. Measuring, characterizing, and modeling the contact behavior of soft materials is still a challenging topic for engineering researchers. In this work, through combination of digital moirAC method and inner-grating approach an experimental technique has… More >

Yang-chun DENG, Gang CHEN

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.1, pp. 27-28, 2011, DOI:10.3970/icces.2011.017.027

Abstract To use material effective and keep pressure vessel safety, large deformation analysis for pressure vessel is very important. Until 2007, the elastic-plastic stress analysis method, that is the first time all over the world, is provided in ASME a.?-2 edition 2007 for boiler and pressure vessel standard that Finite Element Method is used with large deformation analysis. But there is no common recognized direct solution for the carrying capacity of pressure vessels yet and this restrict the application of large deformation analysis in pressure vessel design. This paper investigates the carrying capacity of pressure vessels… More >

T.Y. Wu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.82, No.2, pp. 83-112, 2011, DOI:10.32604/cmes.2011.082.083

Abstract In this work nonlinear analysis of axi-symmetric solid using vector mechanics is performed, in which a triangular solid unit developed in compliance with the concept of vector form analysis is proposed. The vector form analysis uses point value description (rather than function) to describe motion and configuration of solid, which has governing equation directly formulated with respect to each mass point (particle). The point value description includes particles allocation for configuration and defining path elements for particle motion. In addition, constitutive conditions are properly defined to complete the formulation. The constitutive conditions linking the mass… More >

A. Gakwaya¹, H. Sharifi², M. Guillot¹, M. Souli³, F. Erchiqui⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.73, No.3, pp. 209-266, 2011, DOI:10.3970/cmes.2011.073.209

Abstract A mechanical computer aided design and engineering system can be used to reduce the design-to-manufacture cycle time in metal forming process. Such a system could be built upon a solid modeling geometry engine and an efficient finite element (FE) solver. The maintenance of a high-quality mesh throughout the analysis is an essential feature of an efficient finite element simulation of large strain metal forming problems. In this paper, a mesh adaptation technique employing the Arbitrary Lagrangian-Eulerian formulation (ALE) is applied to some industrial metal forming problems. An ACIS boundary representation of the solid model is… More >

P.D.Gosling^1,2, L. Zhang²

CMES-Computer Modeling in Engineering & Sciences, Vol.71, No.3, pp. 203-252, 2011, DOI:10.3970/cmes.2011.071.203

Abstract The analysis of a continuum membrane by means of a discrete network of cables or bars is an efficient and readily tractable approach to the solution of a complex mechanics problem. However, is so doing, compromises are made in the quality of the approximation of the strain field. It is shown in this paper that the original form of the cable-analogy continuum triangle formulation is degraded by an inherent assumption of small strains in the underlying equations, in which the term ßmall" is shown to be "negligibly small". A revised version of this formulation is… More >