Analytical model to evaluate the stiffness of an innovative assembly

摘要

The component method may be used to calculate the initial stiffness of a beam-to-column joint. However, the method presented in NF EN 1993-1-8 is only directly applicable to joints where sections of column and beams are l-profiles. In order to extend this method to innovative joins consisting of a column with a rectangular (or square) hollow section and lattice girders, the paper proposes an analytical model to evaluate the stiffness of an important component of the joint: the out-of-plane deformation of the walls of the tubular column. The applied forces are expressed as a function of the out-of-plane displacements of the four walls of the column in the form of a matrix equation. A system of springs is also proposed to facilitate the modelling of the joint in a finite element calculation software. This spring model avoids a complete 3D modelling of the column walls as well as the ones of the lattice girders.