Розрахунково-експериментальний метод оцінювання вогнестійкості вогнезахищених сталевих конструкцій

Abstract

Physical and mathematical models for assessing the fire resistance of fire-resistant steel structures have been developed. An algorithm is used, which includes experimental and computational procedures in determining the fire resistance of fire-resistant steel structures. The initial and boundary conditions for the construction of these models are formulated, which allow to predict the fire resistance of the fire-resistant steel structure with sufficient accuracy for engineering calculations. The peculiarity of the developed models is taking into account the thermophysical characteristics of steel structures and fire-retardant coatings, the peculiarities of the formation of fire regimes. Based on the proposed physical and mathematical models, a computational and experimental method for estimating the fire resistance of fire-resistant steel structures has been developed. The adequacy of the developed method was checked when assessing the fire resistance of a fire-retardant steel column. A computer model of a fire-retardant steel column was built to simulate non-stationary heating of such a system in the FRIEND software package. The results of determining the convergence of experimental data on the duration of fire exposure at the standard temperature to reach the critical temperature of steel with the results of numerical simulations in the software package FRIEND. Based on the comparison of the experimental results and numerical simulations, a conclusion is made about the adequacy of the developed model to the real processes that occur when heating fire-retardant steel columns without applying a load under fire conditions at standard fire temperature.