Meccanica

, Volume 6, Issue 3, pp 168–171 | Cite as

Upper and lower bounds for the optimum design of structures with random resistance

  • Giannantonio Sacchi
Article

Summary

The expected value of the minimum weight of material necessary for a structure in order to support assigned loads is considered, when the « resistance » of each element is a random quantity.

By going back to a theorem which gives a lower bound for this expected value, a way to compute an upper bound is shown.

A way of evaluating the variation of the interval of the existence of the average is then set out.

Such bounds are functions of random variables but are evaluated on the basis of a deterministic limit design.

Keywords

Mechanical Engineer Civil Engineer Lower Bound Optimum Design Alla 

Sommario

Richiamato un teorema[4] che fornisce un minorante del valore medio del volume minimo di strutture soggette a carichi noti e dotate di elementi costituiti da materiale a resistenza aleatoria, si dimostra l'esistenza di un maggiorante.

Si dimostra poi come sia possibile stabilire un maggiorante ed un minorante della varianza del minimo volume, e quindi come si possa apprezzare il rischio d'errore connesso alla aleatorietà delle resistenze, nella valutazione del volume minimo.

I limiti indicati, benchè derivati da elaborazioni statistiche sulle resistenze, risultano da un progetto ottimale sviluppato con soli calcoli deterministici.

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References

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Copyright information

© Tamburini Editore 1966

Authors and Affiliations

  • Giannantonio Sacchi
    • 1
  1. 1.Istituto di Scienza e Tecnica delle CostruzioniPolitecnico di MilanoItaly

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