Meccanica

, Volume 10, Issue 2, pp 93–98 | Cite as

Dynamic shakedown theory allowing for second order geometric effects

  • Leone Corradi
  • Osvaldo De Donato
Article

Summary

Two necessary and sufficient conditions for shakedown in a structure subjected to given histories of external loads and imposed strains, in the presence of significant inertia and damping effects, are established. Structural discretization and piecewise linearization of constitutive laws are adopted. This permits to consider several hardening materials and geometric effects, in the spirit of second order theory. The statements can be regarded as a generalization to a broader context of the classical Bleich-Melan and Koiter shakedown theorems. With respect to previous work, the main novelty is the simultaneous coverage of dynamic and second order effects.

Keywords

Mechanical Engineer Civil Engineer External Load Order Effect Broad Context 

Sommario

Si dimostrano due condizioni necessarie e sufficienti per l'adattamento in campo elastico di strutture soggette ad assegnate storie di carichi e distorsioni, in presenza di non trascurabili forze d'inerzia e di smorzamento. La discretizzazione della struttura e la linearizzazione a tratti del legame costitutivo consentono di considerare una larga classe di materiali incrudenti e gli effetti geometrici, nello spirito della teoria del second'ordine. Gli enunciati costituiscono una generalizzazione dei classici teoremi di Bleich-Melan e Koiter. A differenza di risultati precedenti, gli enunciati sono validi in presenza di concomitanti effetti dinamici e geometrici del second'ordine.

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Copyright information

© Tamburini Editore s.p.a. Milano 1975

Authors and Affiliations

  • Leone Corradi
  • Osvaldo De Donato
    • 1
  1. 1.Istituto di Scienza e Tecnica delle CostruzioniPolitecnico di MilanoItaly

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