rectilinear crack, local change of plate thickness, contact engagement zone, slippage zone, contact stresses.

A contact problem of partial contacting of rectilinear crack surfaces caused by a local change of the plate material thickness on crack growth path is considered. At some forms of recesses and ratios of their geometric parameters the deformation of elongated plate is decreased in direction perpendicular to the fracture. In this connection stress intensity factor in the crack tip decreased. At some ratios of the geometric parameters of the plate with local thickness changes on the crack growth path a zone of compressive stresses will occur. In this zone of compressive stresses the crack surfaces in a certain section will contact. It is assumed that in some part of the contact zone the engagement of the crack surfaces occurs and in the rest part the slippage is allowed. Determination of unknown contact stresses and sizes of the contact zones is reduced to solving of system of two singular integral equations. Each singular integral equation with the additional conditions is reduced to the Riemann problem, which is solved by quadratures. Normal and tangential stresses in the contact zones are found, as well as the size of the crack contact zones.

Valiyev, Farid Elkhan oglu PhD, Sciences, Researcher, Institute of Mathematics and Mechanics of NAS of Azerbaijan, Azerbaijan, Baku