Resistenza all'incendio di solai a pannelli in legno lamellare incrociato - Fire resistance of cross-laminated timber floors

The paper presents a research on fire resistance of cross laminated timber floors. The aim is to analytically and numerically predict the fire resistance of these floors, and to compare the evaluations with data from experimental full-scale tests. Simplified methods proposed by the Eurocode 5 and by recent research were used for the analytical prediction. A bi-dimensional model was implemented in the finite element code Abaqus to carry out thermal and mechani- cal analyses under fire conditions. Since thermal and mechanical properties of wood are strongly dependent upon the temperature, the variation laws as suggested by the Eurocode were considered in the model. Some full-scale tests on cross-laminated timber panels loaded out-of-plane with a constant load and exposed to fire were performed at Cnr-Ivalsa Timber and Trees Institute in San Michele all'Adige (Tn). The data was used to validate the numeri- cal modelling and to compare with the simplified analytical prediction. It was found that the numerical model can predict the experimental results with good accuracy. The analytical pre- dictions based on the Eurocode 5 approach are slightly non-conservative, and should be re- placed by the approach recently suggested by Schmid et al. for cross-laminated timber since the latter approach was found to be conservative.