Variational Principle of the Variable Boundary for the Contact Problem

The variational principle for the contact problem is derived. The different discontinuities on the contact interfaces of unknown functions, the contact between solids with different physical properties and the boundary variability of contact surfaces are also considered. Contact problems between solids are exactly described. If the effect of boundary variability is missed, the problem is degenerated into a variational formula for solving contact problem with classical variational principle.