Structural expressionism resembles the use of slender structural elements, in particular beam-type elements. To satisfy structural, functional, and also architectural requirements a comprehensive structural analysis must be performed. The main issue of this study is the buckling analysis of beam-type elements, concerning Cavalieri’s principle. The present study is divided into two separate sections. The first part is a theoretical study, in which a variable cross-section beam-type element is modeled. The stability analysis is performed by an indirect variational method and the stiffness of the support connections is also introduced. The numerical simulation highlights 6 cases defined by the restraints of the support connections. The case study follows the modification of the critical buckling load of the variable cross-section beam-type element. Prior to the case study, a novel verification method is proposed to achieve a realistic cross-section for the beam-type element. The study revealed that with ideal characteristics of the stiffness coefficients of the restrains significant increase of the critical buckling load is obtained, and further if an actual situation is considered with finite values of the stiffness of the restrains, the variable cross-section for the beam-type element is a recommended and rational choice to make, to eliminate stability issues.

A correct mass transfer analysis of water vapor in the porous network of concrete is necessary to study the hydro-thermal spelling of concrete-based structural elements. In the case of the mass transfer analysis, one must consider state parameter correlation instead of individual state parameters. This research paper analyzes the available analytical and quasi-empirical relations between the state parameters of the mass transfer analysis. In the case of the quasi-empirical relations, modifications are proposed to be applied to a wider range of situations. A state parameter correlation diagram and analytical relations between the different state parameters are proposed. The proposed analytical relations are verified and validated based on four different approaches.