Effect of the shape of the contact surface of a rigid die with a momentless orthotropic shell of revolution on the magnitude of the contact pressure

It is well known that one of the traits of rational design of a shell of revolution is that its state of stress and strain (SSS) is momentless. Such an SSS cannot always be practically attained because of the nature of the loading and the special features of the design of the shells. However, in some cases, especially for the approximate estimate of the level of the contact pressures the rnomentless statement of the contact problem of an orthotropic shell of revolution with a rigid die may be justified [1]. In the zone of contact 0f a shell with an absolutely rigid fitting (die), its deformations, displacements, and angles of rotation may in most cases be assumed to be small, and on account of the adopted condition of contact normal displacement may be taken to be equal to zero. Then the expression for meridional deformation becomes simplified: