The objective of this study is to obtain the appropriate variational inequa
lities formulation corresponding to shell contact. Specifically, the work i
s concerned with the prediction of the nonlinear deformation behaviour as w
ell as the stress and strain states resulting from contact in thin rings. T
he new formulations account for large deformations and rotations in a total
Lagrangian framework by adopting the second Piola-Kirchhoff stress and the
Green-Lagrange strain measures. In order to validate the newly proposed nu
merical approach, detailed photoelastic and strain gauge measurements were
conducted using different rings. Two aspects of the work were accordingly e
xamined. The first is concerned with the validation of the developed algori
thms, while the second is concerned with the variation of the contact press
ure with the thickness of the ring; The results reveal close agreement betw
een the numerical predictions and the experimentally measured values. (C) 1
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