Doctor of Engineering, The National Institute for Materials Testing, Stockholm,
Pages: 27 Published: Jan 1970
This paper will give a survey of my own investigations in this field, as well as those which have been performed by other authors. The main outlines of an advanced method of fire technical design is described in accordance with the new Swedish regulations. These have been used for only a few months; therefore, the experiences are quite naturally not very extensive. However, it seems as if this method will make it possible to decrease the costs for fire protection without reducing the degree of safety. The method has turned out to be very useful especially when studying steel structures.
Standardized fire tests are based on the assumption that the temperaturetime development of the fire is following the so-called “standard fire curve.” This assumption is extremely simplified and in most cases hardly realistic. On the basis of a simple heat balance equation for the fire cell it is possible to compute the temperature-time development of the fire taking into account all relevant factors such as rate of combustion, amount of fuel (fire load), heat transfer conditions at the heated surfaces, and thermal properties of the structures enclosing and enclosed in the fire. A lot of numerical results will be included in the paper, that is, temperature-time curves for use as alternatives to the standard method which have been included in the new Swedish regulations. On the basis of the computed results there also will be given a proposal for another test procedure which probably will give results closer to those at a real fire.
This paper also will give results from fire tests under very “pure” conditions with wood fuel as well as with kerosine. It has been possible to make comparisons between recorded and computed temperatures, and good correlation is established. The influence of wood fuel on the fire characteristics of varying air supply, amount of fuel, and varying degrees of atomization of the fuel particles has been studied.
Examples will be given of the effect on structural members of different types of temperature-time developments, and some examples of use in structural design of the technique will be described also.
fire test, fire-temperature, combustion, heat transfer, thermal properties, structural members, evaluation, tests
Paper ID: STP44710S