The approach to the formation of the analytical method of evaluation of the stress-strain state of complex rod bearing structural elements is considered in the paper. The prerequisites described cover all the fundamental features of deformation of the components in conditions of tube confined concrete with a strengthened core. This is confirmed by the results of our own experimental studies. The case of central axial compression is considered in detail. From the beginning of loading to destruction of a structural element, two fundamentally different stages of work are distinguished: in the beginning – elastic; closer to destruction – plastic. The method of variable elasticity parameters is used to describe the performance of concrete in the plastic stage. The mutual influence of components during deformation is revealed by solving the contact problem. The methodology was tested by comparing the results of our own experimental and theoretical results.