Extension of the Lack of Knowledge (LOK) theory to force uncertainties

Pierre Ladevèze (1) , Paul Enjalbert (1) , Guillaume Puel (2) , Thierry Romeuf (3)

1 LMT - Laboratoire de Mécanique et Technologie
2 MSSMat - Laboratoire de mécanique des sols, structures et matériaux
3 EADS Space Transportation

This paper deals with the structural modeling of a family of similar, actual structures taking into account uncertainties and modeling errors. The concept of Lack Of Knowledge (LOK), first introduced in [1,2], consists in globalizing the various sources of errors on the substructure using internal variables, called the LOK variables, defined over an interval whose upper and lower bounds follow probabilistic laws. From these basic LOK, we can derive for the whole structure the effective LOK for a quantity of interest a, resulting in an interval with stochastic bounds that we can compare with experimental values. First, errors on the ”structural stiffness” have been considered [1,2,4]. Here we go further, extending the concept of LOK to modelize errors on applied forces, the mathematical framework being the same.

Domaines: Vibrations [physics.class-ph]

Pierre Ladevèze, Paul Enjalbert, Guillaume Puel, Thierry Romeuf. Extension of the Lack of Knowledge (LOK) theory to force uncertainties. IMAC XXIV - Conference & Exposition on Structural Dynamics, 2006, Saint-Louis, United States. pp.CD-ROM. ⟨hal-00258655⟩