摘要:

AbstractThe paper summarizes preliminary work on crash analysis25–27performed on an extended finite element model as provided by the nonlinear LARSTRAN program package at ICA. The essential methodology is evolved along the natural finite element approach. Also overviewed are solution techniques for the nonlinear equations of motion. The application of a simple folding mechanism is indicated and crashworthiness computations of car structures are describe

ISSN:0029-5981    

DOI:10.1002/nme.1620220303

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA rate‐type formulation of quasi‐static boundary value problems using convected material frames is proposed and an associated method of numerical solution is derived. Two numerical problems are presented: the first deals with a significant validation example, the second with a necking bifurcation analy

ISSN:0029-5981    

DOI:10.1002/nme.1620220304

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractWe present in this paper a general formulation for shallow water equations which is capable of solving problems of induced harbour oscillation, tidal flow, tsunami propagation, dispersion of pollutant, etc.The shallow water equations are written in a novel fully conservative form. The solution algorithm is based on an explicit time integration procedure which exploits the conservative properties of the governing equations and incorporates accurate treatment of convective terms without introduction of artificial damping. Its accuracy and low cost of computation make it attractivevis‐à‐visexisting proced

ISSN:0029-5981    

DOI:10.1002/nme.1620220305

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA method for the computation of hydrostatic forces on cable, truss, beam, plate and shell type structures is presented. A general large displacement formulation is assumed which allows for displacements and rotations of unlimited size. Equilibrating forces for nodal points as well as incremental force‐displacement relationships are given. Various ways of making the geometric load matrix symmetric for incremental analysis is discussed. Alternative strategies for the incremental–iterative solution is also treated. A method for the determination of the hydrostatic stability of floating structures is suggested. Metacentres and centres of buoyancy for rotations about principal axes in the water plane are automatically computed. The paper presents three examples of applications: a pipe which is partially submerged, a full overturning of a floating space frame and, finally, a hydrostatic stability analysis of a s

ISSN:0029-5981    

DOI:10.1002/nme.1620220306

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractIn a previous publication1it was suggested that the most fruitful area for the deployment of ‘complicated’ soil models—i.e. those involving more than, say, 6 parameters—lay in analyses of undrained and partially drained problems. The present paper extends previous drained and undrained analyses to the partially drained state, for two rather simple boundary value p

ISSN:0029-5981    

DOI:10.1002/nme.1620220307

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractFirst, the three‐dimensional elasto‐plastic analyses of 1CT and 18 mm thick CCT specimens are carried out by using the finite element method, and the thickness effects of both specimens are studied. In elastic states, there is no significant difference between the CT and CCT specimen in the distribution of theJ‐integral along the straight or curved crack front. However, in elasto‐plastic states, quite the contrary tendency is obtained in the distributions ofJ xand COD along the curved crack front for both specimens. Secondly, elasto‐plastic analyses are carried out for CCT specimens of four kinds of thickness (B= 200, 18, 6 and 4 mm). The distributions of theJ‐integral along the crack front are obtained and compared. Finally, the availability of theJRvalue is examined, which is evaluated from the load versus displacement curve by using Ric

ISSN:0029-5981    

DOI:10.1002/nme.1620220308

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractWe present a new finite element analysis of the linear dynamic responses of a slender fluid–structure system, namely the elasto‐acoustic beam, neglecting flow and viscosity effects. Using one unknown field in the fluid, namely the ‘mass–flow’ corresponding to a cross‐section mean value of the longitudinal displacement field component, an original symmetric formulation is derived which does not exhibit the usual spurious modes associated with the irrotationality constraint occurring in displacements formulations of fluid–struc

ISSN:0029-5981    

DOI:10.1002/nme.1620220309

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractAn unconditionally stable algorithm forplane stresselastoplasticity is developed, based upon the notion of elastic predictor‐return mapping (plastic corrector). Enforcement of the consistency condition is shown to reduce to the solution of a simple nonlinear equation.Consistentelastoplastic tangent moduli are obtained byexact linearizationof the algorithm. Use of these moduli is essential in order to preserve the asymptotic rate of quadratic convergence of Newton methods. The accuracy of the algorithm is assessed by means of iso‐error maps. The excellent performance of the algorithm for large time steps is illustrated in numerical experime

ISSN:0029-5981    

DOI:10.1002/nme.1620220310

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractAn analysis of the elastic–plastic load‐carrying behaviour of thin‐walled spatial beam structures is presented. It is based on a beam theory valid for large displacements and rotations, which admits arbitrary cross‐sections, curved axes, initial imperfections, a general material description, and which fully accounts for the influence of warping constraints as well as the stress‐history dependence of the elastic–plastic shear moduli. An incremental updated Lagrangian viewpoint is adopted in the derivation of the basic beam equations from a generalized variational principle, and in the numerical solution procedure the displacement–finite element approach is followed. The associated tangential stiffness matrices are obtained by direct numerical integration of the governing incremental differential equations rather than through the use of shape functions in connection with a virtual work principle. Applications of the theory are given in which the influence of the loading configuration, material parameters, geometric nonlinearities and warping constraints on the load‐carrying behaviour and on the bifurcation and ultimate loads of thin‐walled beam struc

ISSN:0029-5981    

DOI:10.1002/nme.1620220311

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractWe briefly discuss the requirements on general shell elements for linear and nonlinear analysis in practical engineering environments, and present our approach to meet these needs. We summarize and give further insight into our formulation of a 4‐node shell element using a mixed interpolation of tensorial components, and present a new 8‐node element using this approach. Specific attention is given to the general applicability of the elements and their efficient use in pract

ISSN:0029-5981    

DOI:10.1002/nme.1620220312

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY