Research of wooden bearing structures behavior under fire condition with use advanced methods of fire resistance calculation considering eurocode 5 recommendation

Abstract

The article contains the research results on the behavior of a slab with a wooden frame in the conditions of exposure to fire with standard temperature regime, using the finite element method in ANSYS APDL software under nonlinear formulation. The recommendations of the second parts of Eurocode 1 and Eurocode 5 were used to set the initial data and the boundary conditions for the corresponding tasks. The calculation data were obtained regarding the temperature distributions in cross section of the slab elements and the data on its stress-strain state. The results of the calculations were compared with the experimental data and their adequacy was established. Based on the conducted researches, the calculation method for fire resistance of timber slabs was developed and tested, according to the calculated data on the stress-strain state of the slab under the influence of fire. The proposed methodology is consistent with the approach to the calculation of fire resistance of wooden building structures using the specified method and contains recommendations on basic assumptions, initial data, parameters of boundary conditions, the choice of models of materials, recommendations for building geometric and grid models, as well as the criteria for reaching the loss of fire resistance state.