The paper considers axial,. lateral and rotational displacements about the axis of helically wound rectangular and circular sectioned wires lying on a cylindrical surface which is subsequently bent with a known uniform curvature. The problem reduces to, at the most, a three degree of freedom system in which the stiffness matrix is developed from energy considerations and in which the stiffening effect of wire initial tension can be included. It is assumed that there is rotation of circular wires relative to the underlying cylinder surface but that rectangular wires remain tangential to the cylinder surface. The forces and moments producing wire sliding are those which are induced by the cylinder curvature and modified by frictional effects due to specified contact pressures from adjacent layers. The extreme conditions of no sliding (ie, the infinite friction solution) and unrestrained sliding can be considered very simply. The effect of friction is complicated by the fact that slip may only occur over part of the cylinder circumference. A simple Fourier representation is used for the discontinuous sliding and the associated friction forces but results in the need for an iterative solution. The paper considers some specific cases.
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