“…In particular, if a solution of an equilibrium problem for this type of boundary conditions has nonzero jumps on the crack curve for vertical displacements (deections), then the solution, generally speaking, can have displacements that satisfy the general nonpenetration condition and, nevertheless, for which we have a physically unacceptable phenomenon since there is a mutual penetration of opposite crack faces, see [18]. Therefore, the abovementioned questions of the study of problems for special cases with rened modications of the nonpenetration condition is a justied branch of the development of the mechanics of deformable solids, see, for example, [28,29].…”