Showing papers in "Computer Methods in Applied Mechanics and Engineering in 1996"

TL;DR: In this article, the basic ideas and the mathematical foundation of the partition of unity finite element method (PUFEM) are presented and a detailed and illustrative analysis is given for a one-dimensional model problem.

TL;DR: Meshless approximations based on moving least-squares, kernels, and partitions of unity are examined and it is shown that the three methods are in most cases identical except for the important fact that partitions ofunity enable p-adaptivity to be achieved.

TL;DR: In this article, the authors address the problems of stability and the lack of generalized boundary conditions in the Smoothed Particle Hydrodynamics (SPH) computing technique and propose solutions.

TL;DR: It is shown how h, p and h- p adaptivity can be implemented in the h-p cloud method without traditional grid concepts typical of finite element methods.

TL;DR: In this paper, a material kernel function and an RKPM material shape function are introduced for large deformation analysis of non-linear elastic and inelastic structures based on Reproducing Kernel Particle Methods (RKPM).

TL;DR: In this article, a three-dimensional constitutive model for biological soft tissues and its finite element implementation for fully incompressible material behavior is presented, along with derivations of the stress and elasticity tensors for a transversely isotropic, hyperelastic material.

TL;DR: In this paper, it is shown that nodal integration, like SPH, suffers from spurious singular modes and is treated by the addition to the potential energy functional of a stabilization term which contains the square of the residual of the equilibrium equation.

TL;DR: In this paper, a unified theory for deriving Geometric conservation laws (GCLs) for flow problems with moving boundaries is presented, and the impact of these constraints on the solution of coupled aeroelastic problems, and highlight the importance of the GCLs with an illustration of their effect on the computation of a flat panel in transonic flow.

TL;DR: In this paper, a meshless finite point method for convection-diffusion and fluid flow type problems is presented, which is based on the use of a weighted least-square interpolation procedure together with point collocation for evaluating the approximation integrals.

TL;DR: The basic computational algorithm which includes a recently developed Normalized Smoothing Function is presented, which discusses issues associated with smoothing functions, smoothing distances, free boundaries, material interfaces and artificial viscosity.

TL;DR: The technique employs a string of elements along the essential boundaries and combines the finite element shape functions with the approximation, and the resulting approximation can exactly reproduce linear polynomials so that it satisfies the patch test.

TL;DR: In this paper, a multiple scale finite element model (VCFEM-HOMO) was developed for elastic-plastic analysis of heterogeneous (porous and composite) materials by combining asymptotic homogenization theory with the Voronoi Cell finite element models.

TL;DR: The improvements in the methodology, in particular the introduction of spectral degrees of freedom, result in a fast and accurate method, significantly more efficient than the Finite Element Method or Element Free Galerkin Method.

TL;DR: In this article, two efficient solution procedures are presented that dramatically reduce the amount of computations involved in numerically solving these problems and demonstrate that the linear algebraic systems from the underlying SSFEM formulation can be solved with considerably less effort in memory and computation time than their size suggests.

TL;DR: A theoretical framework is presented to explain the cause of grid-scale anomalies in the numerical solutions to optimization problems, similar to those that are sometimes encountered in mixed formulations of the Stokes problem.

TL;DR: In this article, an algorithm for the numerical computation of so-called consistent tangent moduli in finite inelasticity is presented, where the moduli determine the sensitivity of algorithmic expressions for stresses with respect to the change in total deformation.

TL;DR: In this article, a 3D finite element flow simulation capability for fluid-particle interactions is presented and applied to study time-dependent behavior of multiple spheres falling in a liquid-fluid tube.

TL;DR: The material point method as discussed by the authors is an evolution of particle-in-cell methods which utilize two meshes, one a material or Lagrangian mesh defined over material of the body under consideration, and the second a spatial or Eulerian mesh defining over the computational domain.

TL;DR: In this paper, a back propagation algorithm was used to train a neural network for reliability analysis of complex structural systems in connection with Monte Carlo Simulation (MCS), and the trained NN was then used to compute the critical load factor due to different sets of basic random variables.

TL;DR: In this paper, a finite shell element for large deformations is presented based on extensible director kinematics, which is an interface to arbitrary three-dimensional material laws and is characterized by a course mesh accuracy and distortion insensitivity compared with bilinear displacement approaches.

TL;DR: In this article, a methodology is introduced for the development of adaptive methods for hierarchical modeling of elastic heterogeneous bodies, based on the idea of computing an estimate of the modeling error introduced by replacing the actual fine-scale material tensor with that of a homogenized material, and to adaptively refine the material description until a prespecified error tolerance is met.

TL;DR: In this article, a predictor-corrector explicit time integration algorithm is presented for solving structural dynamics problems, which is based on the implicit generalized-α method developed by the authors.

TL;DR: An approach to unify reproducing kernel methods under one large umbrella and an extension to include time and spatial shifting are proposed, and the Hermite reproducingkernel particle method, a particle based discrete version of the Hermites kernel method is developed.

TL;DR: Element Free Galerkin methods are methods for solving partial differential equations with the help of shape functions coming from Moving Least Squares Approximation that are more flexible than the Finite Element method.

TL;DR: In this article, the identification of parameters for inelastic material models is performed in the frame of the finite element method, where linearization procedures are described in a systematic manner for the case of complex material models within a geometric linear theory.

TL;DR: In this paper, a nonlocal continuum plasticity theory is presented, which is defined as a certain weighted average of the corresponding local field, taken over all the material points in the body, where a quantity with the dimension of length occurs as a material parameter.

TL;DR: In this paper, the weighted integral method and the Monte Carlo simulation are used together with innovative solution strategies based on the Preconditioned Conjugate Gradient method (PCG) to produce robust and efficient solutions for the stochastic finite element analysis of space frames.

TL;DR: In this article, the appearance of these modes is investigated analytically by means of a simple representative example, and it is shown that in compressive deformation states these elements depict stability modes which are associated with hour-glass forms and thus denote a rank deficiency for such deformations.

TL;DR: In this article, a detailed comparison of two implicit time integration schemes for a simple non-linear Hamiltonian system with symmetry was presented, where the motion of a particle in a central force field was investigated.

TL;DR: In this article, a model of solids made from polygonal cells connected via beams is presented for the simulation of fragmentation processes, and the effects of an explosion inside a circular disk and the impact of a projectile are investigated.