NUMERICAL PROCEDURE FOR CALCULATION OF TEMPERATURE EVOLUTION IN COMPOSITE ELEMENTS WITH INTERNAL CAVITIES

In the paper a computation code based on the finite-element method for temperature evolutions in composite elements with internal cavities i s presented. It is suitable for the analysis of various thermal proble ms encountered in mechanical and civil engineering such as fire risk a ssessment. It is based on a plane isoparametric triangular element wit h six nodes allowing the modelling of curved boundaries. In order to a nalyse composite steel-concrete elements and to take into account the non-linearities coming from the temperature-dependent material propert ies and from the boundary conditions, an implicit integration scheme i s used. Another advantage of the program is the possibility of describ ing internal cavities with convection and radiation exchanges. In orde r to show the capacity of the program two examples are presented. Comp arisons have been made with experimental and other numerical results, exhibiting very good agreement.