Showing papers in "Computer Methods in Applied Mechanics and Engineering in 1977"

TL;DR: In this paper, the linear elastic, stiffness-derivative, finite element technique was generalized to determine the ductile fracture parameter J from elastic-plastic finite element solutions, based on energy comparison of two slightly different crack lengths.

TL;DR: In this article, it was shown that many commonly used one-step algorithms which are unconditionally stable for linear transient heat conduction problems become conditionally stable in the nonlinear regime.

TL;DR: In this article, a powerful finite element formulation for plate bending has been developed using a modified version of the variational method of Trefftz, and the notion of a boundary has been generalized to include the interelement boundary.

TL;DR: In this article, mixed-hybrid finite element approximations are described for second-order elliptic boundary value problems, in which independent approximation methods are used for the solution and its gradient on the interior of an element and the trace of the gradients on the boundary of the element.

TL;DR: In this paper, a simple facet triangular plate and shell finite element called TRUMP is described, if required, transverse shear deformation and is based on physical lumping ideas with a simple mechanical interpretation, and an account of some non-trivial numerical examples of large deflection and postbuckling of shells.

TL;DR: In this article, a program to evaluate complete stress distributions has been developed and applied to the extrusion process, and the results show that the resulting stress fields exhibit features consistent with the known development of extrusion defects, such as the appearance of surface cracks.

TL;DR: In this article, a method for accelerating the convergent iterative procedures of solving the system of linear equations X = AX + f is presented, where the number of eigenvalues of A that are greater in absolute value than unity is not very large.

TL;DR: In this paper, the authors present a three-dimensional elastostatic analysis based on curved quadrilateral and triangular elements, where the elastic body is divided into subrogions so that the matrix is of banded form, and coefficients are evaluated using Gaussian quadrature formulas.

TL;DR: In this article, several finite element in time algorithms are developed based on Hermitian expansions of increasing order which are then compared with Pade approximations and alternative Norsett formulas.

TL;DR: In this article, the authors presented some extensions and further numerical results of finite elasto-plastic strain analysis of structures which was initiated in part I of this paper, and fundamental refinements of the proposed incremental method of analysis are given and demonstrated on actual numerical computations.

TL;DR: In this article, a numerical procedure based on the finite element method is developed for the analysis of general two-dimensional problems in free/forced convection heat transfer, and the dicretization of the field equations through use of the Galerkin method is described.

TL;DR: In this paper, a mixed curved-beam finite element was developed for the geometrically nonlinear analysis of deep arches based on a form of the nonlinear deep-arch theory with the effects of transverse shear deformation and bending-extensional coupling included.

TL;DR: The combination of the simultaneous iteration and the Lanczos method with the generalized Rayleigh quotient is shown to give two powerful methods for solving large quadratic eigenproblems arising in many engineering applications.

TL;DR: In this article, mixed shear-flexible isoparametric elements are presented for the stress and free vibration analysis of laminated composite shallow shells, both triangular and quadrilateral elements are considered.

TL;DR: In this article, a piecewise linear approximation to an arbitrary yield function is constructed in the course of solving a given boundary value problem, and its use is illustrated with some simple examples.

TL;DR: In this paper, the authors extended the stress computation concept described in [1] to arbitrary meshes and elements, in particular to triangular elements, using complete and conforming displacement models, and assuming linear stress distributions and corresponding virtual displacements at element peripheries.

TL;DR: In this article, the coefficients in the algebraic perturbation equations for the terms up to the third degree are easily evaluated once the lowest buckling modes of the structure have been determined.

TL;DR: In this paper, a procedure for numerical solution of the time-dependent equations governing the flow in a crystal-growth crucible is described, where the molten crystal material is taken to be a Newtonian fluid with constant viscosity.

TL;DR: In this paper, the choice of an optimum approximate integration operator for systems of first order linear differential equations is discussed, with emphasis on the achievable accuracy, including a family of one-step direct schemes and a new modally uncoupled operator, both using a piecewise lincar representation of the forcing function.

TL;DR: The general method used in treating the three-dimensional boundary conditions is illustrated here through comparison of computed surface pressure time histories with the corresponding experimental data for a plane-shock wave passing over a rectangular parallelepiped.

TL;DR: An internal variable model is developed for concrete creep with the following features: creep strain is a linear functional of stress history; application or removal of stress produces instantaneous elastic response; upon removal of Stress, creep deformations partially recover, approaching in the limit an irrecoverable part.

TL;DR: In this article, the problem of optimising multilaminar fiber-reinforced continua is decomposed into an inner and an outer sub-problem, where the primary optimisation variables are the nodal deflections of the finite element model.

TL;DR: In this paper, the Galerkin method is applied to the solution of Burgers' equation and a nonlinear wave equation, using expansions of B -splines of increasing number of terms and order of spline.

TL;DR: The first algorithm is a generalization of the iterative method of successive coordinate overrelaxation of p vectors are iterated simultaneously in such a way that they converge ultimately towards the eigenvectors corresponding to the p smallest eigenvalues.

TL;DR: In this article, the slender channel approximate equations are used to describe flows in curved channels of varying height, and a second-order accurate Crank-Nicolson finite difference scheme is developed with the pressure treated directly as one of the dependent variables.

TL;DR: In this article, the problem of minimum-cost design of rigid-plastic circular plates under axysymmetric loading is studied by the variational approach and the optimality condition is discussed for absolute and technological constraints.