摘要:

AbstractThis paper is a user's guide for the stand‐alone explicit direct time integration package STINT/CD for structural dynamics analysis. STINT/CD uses an automatic variable time increment central difference method. The purpose, function, limitations and usage of the package are described. A FORTRAN listing of STINT/CD is given along with a sample problem which illustrates its usage and performanc

ISSN:0029-5981    

DOI:10.1002/nme.1620170902

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractThis paper describes and efficient method for computing two‐dimensional element stiffness matrices. It is a generalization of the algorithm given by Taylor.1Theory is developed for elements which are loaded under plane stress, plane strain or axisymmetric conditions, and two FORTRAN IV subroutines are included. These subroutines, which are presented in a modular form, are applicable to any type of serendipity, Lagrangian or triangular element, and may be incorporated into a user's library. Alternatively, if desired, the relevant code may be embedded directly into existing stiffness generation routine

ISSN:0029-5981    

DOI:10.1002/nme.1620170903

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

ISSN:0029-5981    

DOI:10.1002/nme.1620170904

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractThe problem of harmonic waves in layered and fibre‐reinforced composites is solved by a method of finite elements. Piecewise linear approximating functions are used for the displacement and stress fields in a mixed variational formulation, recently proposed by one of the writers in the form of a new quotient. Numerical computations are made for approximate phase‐velocities of harmonic waves in layered composites, where asymmetric and symmetric triangular meshes, and square meshes with interior nodes, are used. To illustrate the accuracy and effectiveness of the method, these approximate solutions are compared with those given by means of exponential test functions, and the exact ones by Rytov, etc. Calculations are also performed for harmonic waves in fibre‐reinforced composites. Dispersion curves for these waves are obtained and displayed graphi

ISSN:0029-5981    

DOI:10.1002/nme.1620170905

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractTwo of the most promising localized finite element methods are compared: the boundary series element method, in which a series of eigenfunctions is used to represent the far field solution; and the boundary integral element method, in which an integral equation is satisfied at the boundary between localized finite element and outer regions. The methods are applied to water of arbitrary depth. The theory of the two methods is summarized, and typical numerical results are discussed. Consideration is given to the well‐known hydrodynamical reciprocal relations, and to the phenomenon of ‘irregular’ frequencies. The relative merits of the two methods are establ

ISSN:0029-5981    

DOI:10.1002/nme.1620170906

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractA finite difference solution of a system of first‐order partial differential equations, using a central difference scheme, is presented. The equations describe the linear elastic behaviour of a thick rectangular plate resting on an elastic foundation and carrying an arbitrary transverse load. The lateral edges of the plate are unstressed. The main deflections and stresses predicted by the method for a particular case are given, together for purposes of comparison, with results from a finite element analysi

ISSN:0029-5981    

DOI:10.1002/nme.1620170907

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractQuadratic and cubic quadrilateral isoparametric elements are investigated for use as transition elements for use a crack tip elements. Computations for a single element are explicitly carried out using a symbolic algebraic manipulation program and in addition to the desired square root singularity, additional singularities are revealed. Cubic transitional elements were used for a double‐edge crack problem and only marginal improvement is found for a well‐laid out g

ISSN:0029-5981    

DOI:10.1002/nme.1620170908

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractThe displacement and strain fields of thin‐walled pretwisted beams are prescribed in terms of generalized displacements for extension, bending, torsion and warping. Differential equations and boundary conditions are obtained from the elastic potential energy functional without assuming coincidence of the beam axis with any of the structural axes. This procedure gives a unique consistent definition of sectional moments and generalized forces. Some simple explicit formulae are derived for homogeneous tension–torsion. For the general case a computer code is developed on the basis of discretized generalized displacements and a modified energy functional, devised to obtain consistent lengthwise variation of the stresses and a unique decomposition of the torsional moment. Examples show agreement with analytical results for cylindrical beams and illustrate the various coupling effects for beams with pretwist. They also demonstrate the usefulness of the explicit formulae for homogeneous tension–to

ISSN:0029-5981    

DOI:10.1002/nme.1620170909

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

ISSN:0029-5981    

DOI:10.1002/nme.1620170910

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

ISSN:0029-5981    

DOI:10.1002/nme.1620170911

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY