EACS 2016 Paper No. 121
The paper presents development and application of a thermomechanical static solver based on the Finite Element Interconnecting Method (FETI) to be employed in hybrid fire tests. Hybrid fire test produces a time-history response of a hybrid model that comprises numerical and physical substructures to combined mechanical and thermal excitation. Hybrid fire test is advantageous to whole building full-scale fire tests because it allows testing of structural elements that exhibit a highly nonlinear fire behaviour in relatively small furnaces under realistic boundary conditions derived from a numerically model of the remainder of the structure. On these premises, the paper comprehensively describes the proposed static solver by highlighting its ability to guarantee compatibility and equilibrium at the interface between the physical substructure (PS) and the numerical substructure (NS), both for non-floating and floating subdomains as well as for nonlinear behaviour of the PS. The development of the solver has been driven by laboratory practice: an error propagation analysis that takes into account errors and uncertainties, such delay and measurement noise, is incorporated. The validation carried out in a fully numerical framework, i.e. the PS is also numerically modelled, shows promising outcomes for future experimental implementations.