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This article is about the principle in solid mechanics. For the prisoner rehabilitation concept practiced in Norway, see normality principle.
The Principle of normality in solid mechanics states that if a normal to the yield locus is constructed at the point of yielding, the strains that result from yielding are in the same ratio as the stress components of the normal.
References
Richards, Rowland Jr. (2001). Principles of Solid Mechanics. Boca Raton, Florida: CRC Press LLC. p. 446. ISBN0-8493-0114-9.
Hosford, William (2010). Solid Mechanics. Cambridge: Cambridge University Press. p. 274. ISBN9780511722615.