Development, research and verification of correct mathematical models and methods of structural mechanics are the most important aspects of ensuring safety of buildings and complexes. The distinctive paper is devoted to semianalytical solution of multipoint boundary problems of structural analysis with the use of combined application of finite element method and discrete-continual finite element method. Structures containing parts (subdomains) with regular (in particular, constant or piecewise constant) physical and geometrical parameters in some dimension are under consideration. Operational formulations of two-dimensional and three-dimensional problems of structural mechanics with the use of so-called method of extended domain, corresponding numerical implementations (including construction of discrete (finite element) and discrete-continual approximation models for subdomains) and numerical examples are presented.