Elastic Limit Load Research Articles

Dynamic buckling of thin isotropic plates subjected to in-plane impact

The dynamic stability behaviour of imperfect simply supported plates subjected to in-plane pulse loading is investigated. For the calculation of dynamic buckling loads a stress failure criterion is applied. The large-deflection plate equations are solved by a Galerkin method by using Navier's double Fourier series. In this paper the dynamic load factor (DLF) is redefined and plots that are useful for the design of plate structures are presented. Parametric studies are performed in which the influences of the pulse duration, shock function, imperfection, geometric dimensions and limit stress of the material are discussed. Comparison between the dynamic buckling loads, which are obtained by the commonly used criterion of Budiansky and Hutchinson [Proceedings of the 11th International Congress of Applied Mechanics (1964) 636], and the dynamic elastic limit loads, which are computed by the stress failure criterion, shows that the latter criterion is more useful for the design of lightweight structures.

Stress Analysis and Design for Cyclic Loading

A finite element implementation of rapid cycle analysis is described and demonstrated. It forms part of a comprehensive framework for static structural analysis which consists of: linear elastic analysis, limit load or nonlinear elastic analysis, and rapid cycle analysis. This approach allows for complex material and loading behavior, but is computationally more efficient and easier to perform than full inelastic analysis. It indicates more complex behavior than can be inferred from linear elastic analysis. The objective of this paper is to calculate shakedown, reverse plasticity, ratcheting, and the increase in strain rate as a result of cyclic mechanical and thermal loading. Results are presented in the form of interaction diagrams, similar to the O’Donnell-Porowski plot in the ASME BPV Code, which are effective design tools. [S0094-9930(00)01604-8]

Elastic limit loads of skew plates

An elastic limit load of skew plates is analyzed on the basis of the Rayleigh-Ritz method with B-spline functions and the Huber-Mises yield criterion. Dimensionless elastic limit loads, associated maximum deflections and the positions of the first yield points are presented for different skew angles, aspect ratios and boundary conditions.

Plane stress shakedown analysis by finite elements

The determination of the maximum load domain that is safe with respect to shakedown is formulated as a mathematical programming problem by means of a finite element technique for plane stress problems. The method is applied to a slab with a circular opening subjected to biaxial loading. Results obtained show that slabs with openings shake down under loads considerably greater than the elastic limit loads.