MATHEMATICAL MODELLING OF HEAT CONDUCTION BY ELEMENTS OF BUILDING CONSTRUCTIONS DURING THE FIRE

Abstract

The article deals with the one-dimensional problem of heat conduction during a fire by elements of building construction – brick and concrete walls as well as a metal through a wall rod. The boundary conditions at the beginning of the construction are the standard fire curve and at the end of it – the 3rd kind boundary condition which describes the heat emissi on in environment according to Newton law. The differential equation of heat conductivity with the corresponding initil and boundary conditions is solved numerically using constant values of heat conductivity and thermal capacity as well as depending on temperature ones. Decrease of fire resistance boundary of building construction as the result of through metal elements presence in them is proved theoretically.