Thermo-mechanical model of a cardboard-plaster-cardboard composite plate submitted to fire load and experiments

S. Sakji (1, 2) , Christian Soize (2) , J.-V. Heck (1)

1 CSTB - Centre Scientifique et Technique du Bâtiment
2 LaM - Laboratoire de Mécanique

Generally, the standard rules require conventional tests at scale one in order to justify the fire resistance of loaded plasterboard-lined partitions. This paper corresponds to a project whose objectives are to develop a numerical simulation model validated with experiments in order to predict thermo-mechanical overall partition behaviour. This research is organized in four steps. The first step is to set on an experimental then-no-mechanical data base for multilayer cardboard-plaster-cardboard(CPC). These tests are carried out using a new testing bench specially developed for this research. A full description of this device is given in the paper. In order to prepare the implementation of a probabilistic model for the CPC multilayer, several tests are performed for different thermo-mechanical configurations. The second step of the research is the development of a complete thermo-mechanical model for CPC multi-layer plates. The developed model is adapted to a range of temperatures for which the cardboard and the plaster can be destroyed. The mathematical-mechanical model has been developed in order to simulate the thermo-mechanical behaviour of the CPC panels subjected to a heat flow corresponding to the ISO 834 function. Numerical simulations performed with a dedicated finite element code are presented. The third step is the identification of the thermo-mechanical parameters for each material of the CPC plasterboard. Thermo-mechanical bending tests for plaster and thermo-mechanical tensile tests for each cardboard are performed. Results show an important dispersal of the Young modulus which will justify the implementation of a probabilistic model which is still in progress. The fourth step consists in comparing numerical results to the thermo-mechanical experiments of step one and to validate. the developed model.

Mots clés: thermo-mechanical model; cardboard-plaster-cardboard; composite plate; su fire load

Domaines: Mécanique des matériaux [physics.class-ph]; Mécanique des matériaux [physics.class-ph]; Thermique [physics.class-ph]; Thermique [physics.class-ph]

S. Sakji, Christian Soize, J.-V. Heck. Thermo-mechanical model of a cardboard-plaster-cardboard composite plate submitted to fire load and experiments. 2nd International Conference on Computation Methods and Experiments in Material Characterisation Location: Portland, ME Date: NOV 02-04, 2005, Nov 2005, Portland, ME, United States. pp.Pages: 133-140. ⟨hal-00686189⟩