Wei Wu^1,2,3, Yaji Jiao^2,*, Hehua Zhu^1,2,3, Rui Jin²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.21, No.2, pp. 33-33, 2019, DOI:10.32604/icces.2019.05324

Abstract When shield tunnels pass through gas-bearing strata, leakage may happen through the gasketed segmental joints, which puts threats on the safety during construction and operation process. Previous studies on sealing performance of the gasketed joints have focused on the waterproof behavior. However, differences in physical characteristics between liquid and gas, lead to different permeation properties. This paper presents a combined experimental and computational study to investigate the gas sealing behavior of the gasketed joints used for a shield tunnel project, i.e., Sutong GIL Utility Tunnel, which passes through soft soil strata rich in high-pressure biogas under Yangtze River. As double-gasket… More >

O. Allix¹, P. Gosselet¹, P. Kerfriden², K. Saavedra³

CMC-Computers, Materials & Continua, Vol.32, No.2, pp. 107-132, 2012, DOI:10.3970/cmc.2012.032.107

Abstract This paper deals with the parallel simulation of delamination problems at the meso-scale by means of multi-scale methods, the aim being the Virtual Delamination Testing of Composite parts. In the non-linear context, Domain Decomposition Methods are mainly used as a solver for the tangent problem to be solved at each iteration of a Newton-Raphson algorithm. In case of strongly non linear and heterogeneous problems, this procedure may lead to severe difficulties. The paper focuses on methods to circumvent these problems, which can now be expressed using a relatively general framework, even though the different ingredients of the strategy have emerged… More >

L. Dong¹, A. Alotaibi², S.A. Mohiuddine², S. N. Atluri³

CMES-Computer Modeling in Engineering & Sciences, Vol.99, No.1, pp. 1-85, 2014, DOI:10.3970/cmes.2014.099.001

Abstract In this expository article, a variety of computational methods, such as Collocation, Finite Volume, Finite Element, Boundary Element, MLPG (Meshless Local Petrov Galerkin), Trefftz methods, and Method of Fundamental Solutions, etc., which are often used in isolated ways in contemporary literature are presented in a unified way, and are illustrated to solve a 4^th order ordinary differential equation (beam on an elastic foundation). Both the primal formulation, which considers the 4^th order ODE with displacement as the primitive variable, as well as two types of mixed formulations (one resulting in a set of 2 second-order ODEs, and the other resulting… More >

Bin Gu^1,2,3, L. C. Zhang², Weifeng Yuan¹, Youjun Ning¹

CMES-Computer Modeling in Engineering & Sciences, Vol.88, No.4, pp. 309-324, 2012, DOI:10.3970/cmes.2012.088.309

Abstract Bridging the atomic and continuous analyses is an important aspect in multi-scale mechanics. This paper develops a computational method to integrate the atomic potential of a material with the finite element method. The novelty of this method is that strain energy is calculated from the atomic potential without the assumption in the Cauchy-Born rule that deformation in a virtual atomic cell is homogeneous. In this new method, the virtual atomic cell deformation is interpolated according to the continuum displacements associated with the shape functions. The applications of the method to single crystal Si and Ge bars under uniaxial tension and… More >

H.W. Zhang^1,2, J. Lv¹, Y.G. Zheng¹

CMES-Computer Modeling in Engineering & Sciences, Vol.68, No.1, pp. 55-94, 2010, DOI:10.3970/cmes.2010.068.055

Abstract A new multiscale computational method named as extended multiscale finite element method is proposed for the mechanical analysis of closed liquid cell materials. The numerical base functions for both the displacement field and the pressure of the incompressible fluid within the closed cells are employed to establish the relationship between the macroscopic deformation and the microscopic variables such as deformation, stress, strain and fluid pressure. The results show that the extended multiscale finite element method constructed with the conventional four-node quadrilateral coarse-grid elements sometimes will have strong boundary effects and cannot predict well the fluid pressure in the closed cells.… More >

R.L. Huston¹, C.-Q. Liu²

CMES-Computer Modeling in Engineering & Sciences, Vol.10, No.2, pp. 143-152, 2005, DOI:10.3970/cmes.2005.010.143

Abstract This paper presents a summary of recent developments in computational methods for multibody dynamics analyses. The developments are presented within the context of an automated numerical analysis. The intent of the paper is to provide a basis for the easy development of computational algorithms. The principal concepts discussed are: differentiation algorithms, partial velocities and partial angular velocities, generalized speeds, Euler parameters, Kane's equations, orthogonal complement arrays, lower body arrays and accuracy testing functions. More >

M.Ganesh¹, D. Sheen²

CMES-Computer Modeling in Engineering & Sciences, Vol.2, No.2, pp. 183-194, 2001, DOI:10.3970/cmes.2001.002.183

Abstract A parallel numerical algorithm is introduced and analyzed for solving inhomogeneous initial-boundary value parabolic problems. The scheme is based on the method recently introduced in Sheen, Sloan, and Thomée (2000) for homogeneous problems. We give a method based on a suitable choice of multiple parameters. Our scheme allows one to compute solutions in a wide range of time. Instead of using a standard time-marching method, which is not easily parallelizable, we take the Laplace transform in time of the parabolic problems. The resulting elliptic problems can be solved in parallel. Solutions are then computed by a discrete inverse Laplace transformation.… More >

J.C. Michel¹, H. Moulinec, P. Suquet

CMES-Computer Modeling in Engineering & Sciences, Vol.1, No.2, pp. 79-88, 2000, DOI:10.3970/cmes.2000.001.239

Abstract An iterative numerical method based on Fast Fourier Transforms has been proposed by \cite{MOU98} to investigate the effective properties of periodic composites. This iterative method is based on the exact expression of the Green function for a linear elastic, homogeneous reference material. When dealing with linear phases, the number of iterations required to reach convergence is proportional to the contrast between the phases properties, and convergence is therefore not ensured in the case of composites with infinite contrast (those containing voids or rigid inclusions or highly nonlinear materials). It is proposed in this study to overcome this difficulty by using… More >