VALIDATION OF METHODS FOR DETERMINING THERMAL PERFORMANCE OF FIRE PROTECTION SYSTEMS OF STEEL STRUCTURES

Abstract

This article presents the procedure for the validation of methods for determining the thermal performance of fire protection systems of steel structures, based on conducting a full-scale (validation) experiment, which ensures the automation of the validation process. This procedure includes the stages of experimental determination of the temperature of samples of steel structures (beams, columns 1.0 m long), equipped with a certain fire protection system, under the conditions of fire exposure at a standard temperature regime, calculation of thermal performance according to the methodology given in the standards EN 13381-4 and EN 13381-8, and according to the method, which is based on solving the inverse problem of thermal conductivity and the optimization problem, and comparing the calculated and actual values of the determining performance. The method of conducting the validation experiment, regulated in the procedure, corresponds to that given in the specified standards, except that it does not use loaded samples (beams or columns) intended for evaluating the ability of the fire protection system to bond. The applied mathematical model for determining the calculated values of the coefficient of thermal conductivity of the fire protection material and the required minimum thickness of the fire protection corresponds to that given in the specified standards. In the mathematical model, which is used in the validation procedure to determine the valid (conditionally accurate) values of the thermal conductivity coefficient and the required minimum thickness, the boundary conditions of complex convective-radiative heat exchange (coefficients of heat transfer and thermal radiation, as well as the temperature in the furnace) are set on the heating surface of the fire protection system. It was determined that in order to ensure the automation of the validation process according to the specified procedure, it is necessary to develop and implement an intelligent temperature control system in the furnace, as well as a software product that ensures the automation of the input process and the preservation of input and output data necessary for the implementation of the validation procedure, as well as the development solving the inverse heat conduction problem and the optimization problem.