“…An alternative approach to the formulation of crack problems that excludes mutual penetration of the crack faces has been investigated since the 1990s. This approach is characterized by the Signorinitype boundary conditions at the crack faces [1,2,[12][13][14][15][16][17][18][19][20][21]. In the last 10 years, within the framework of crack models subject to non-penetration (contact) conditions, a number of papers have been published concerning shape optimization problems for delaminated rigid inclusions; see, for example, [2,[22][23][24][25][26][27].…”