A variant of the numerical-analytical method in the nonlinear mechanics of reinforced concrete is proposed. Calculation models make it possible to take into account a number of important factors, such as discrete cracks, the effect of concrete discontinuity, and reinforcement reactions in a crack. When solving the inverse problem of determining the width of the crack opening, the deformation effect is not set, but is modeled using the “joining” of the assigned minimum possible width, its opening under the appropriate loading. In the calculation scheme, pairs of finite elements are distinguished, adjacent to such a crack from opposite special sides, called a two-element cantilever model. Pairs are considered in two states: before their jointing of cracks and after their jointing, taking into account the deformation effect and the effect of concrete discontinuity. The calculation algorithm is based on combinations of an analytical model for calculating the stiffness of complexly stressed structures and the intelligence of the “LIRA-SAPR” software package.