On the influence of clearance in orthotropic disc-pin contacts

摘要

Solutions to contact problems are important in mechanical as well as in civil engineering, and even for the most simple problems there is still a need for research results. In the present paper we use an alternative super element procedure to solve directly, without iteration and incrementation, an orthotropic disc-pin contact problem. The most simple solutions are named Hertz solutions (from 1882), and we use one of these solutions for comparison with finite element results. As a function of the total contact force we find (inversely) the size of the contact area, the distribution of the contact pressure, and the contact compliance. In models of finite size the compliance depends on the flexibility of the total model, including the boundary condition of the model, and therefore disagreement with the locally based analytical models is expected. The examples of an earlier paper were restricted to axisymmetric problems with isotropic, elastic materials and excluding friction. In the present paper we restrict to the two-dimensional problems of conforming cylindrical contact with focus on the orthotropic disc-pin contact where the hole is in an orthotropic disc, i.e., in a non-isotropic material. Especially the indentation (penetration, normal approach) is badly estimated by the analytical methods and therefore deserves special attention. Results from a number of parameter studies of the influence of clearance is presented, and from this follows that some almost linear relations are found. It is concluded that a simple analytical Hertz formula is useful, but it cannot give detailed information.