Fire Resistance Behavior Research Articles

Fire resistance of composite slim floor beams

There is an increasing interest in the steel-concrete composite slim floor construction in the Nordic Countries and the UK. The slim floor beams, which are partly contained within the floor slab, have inherent good performance under fire. At the moment, a new type of slim floor beam is under development in Finland. In this paper, the thermal and structural performance of this new slim floor beam is investigated under fire by using numerical analysis programs. The temperature analysis and calculations of the load-bearing capacity are carried out under fire conditions (both ISO standard fire and natural fire) according to Eurocode 1 Part 2.2. The structural fire resistance behaviour of this new slim floor beam is investigated and the relationship between the fire resistance time and load ratio under ISO standard fire is discussed. Moreover, the minimum load ratio of the beam under a natural fire is analyzed. The critical relationship between the minimum load ratio and the fire parameters (opening factor and fire load density) is also established, provided that the structural failure is caused by a reduction in the flexural capacity of the fire-exposed beam.

Performance-based fire resistance design of concrete-filled steel columns

A simplified design equation for evaluating the fire resistance of concrete-filled circular and square hollow structural steel (HSS) columns is presented. The equation is expressed in terms of various structural design parameters affecting the fire resistance, and hence can easily be integrated into conventional structural design. This equation can be used to evaluate the fire resistance of HSS columns filled with various types of concrete filling. The use of the design equation greatly facilitates the calculation of the fire resistance of structural members on a performance basis. It also enables the designer to find cost-effective solutions in providing the required fire resistance performance for structural members, simply by varying the parameters of the members. The applicability of the proposed equation to a design situation is illustrated through a numerical example. Practical guidelines that can be implemented during the design and construction phase, and which have beneficial effects on the fire resistance behaviour concrete-filled of hollow steel columns, are also presented.

Fire Resistance Tests of Various Fire Protective Coatings

Tests were carried out on more than 14 different samples of fire protective coatings in order to investigate a relation between the thickness of the intumescent fire protection coating and the time of exposure to heat. A number of coatings of different chemical composition enabled to determine the fire resistance behaviour patterns. During test the one-side and volumetric methods were employed in observance of the standard temperature-time curves. For one-side method, the coating was applied on one side and all edges of the specimen, whereas for volumetric test the specimens were completely covered with fire protective coating. It is shown that a layer of coating protects the specimen's surface from heat exposure for a certain period of time until full oxidation of the coating occurs. The efficiency of fire protective coatings also depends on thickness of the charred layer of the side exposed to heat.http://dx.doi.org/10.5755/j01.ms.17.1.257