Aim: The authors carried out an analysis of modern technologies with the aim of improving the functional effectiveness of building structures including thermo-mechanical properties. They verified an effective method of increasing fire resistance of metal structures by the use of fire-retardant coverings and sidings which act as thermal insulation screens. These protect the surface of structures from heat exposure during a fire incident and increase the time during which the structure maintains its fire resistance. The purpose of this work is to perform an experimental study of inert fire protection coverings for metallic structures.

Methodology: The authors described inert protective coverings for metal structures known as fire-retardant coating which, do not change their physical properties under the influence of high temperatures. Because of physical and thermal characteristics such coverings provide protection against fires. After an analysis of established methods used for determining fire resistance capability, the authors utilised one such method to test a sample covering. Thermo-couples were positioned on experimental structures and in the furnace so that temperature control could be maintained. Subsequently a different thickness of covering was applied to the sample and results observed. The benefit of such an approach rests with the way results can be obtained and conclusions drawn, without additional mathematical calculations. For the benefit of this study two samples were prepared, made up from heat-insulating construction aerated concrete D 800 and D 500, and a high-temperature binder (adhesive). Research results revealed that the temperature limits for heated metal plates were achieved. Corresponding protection time for aerated concrete plates D 400 and D 500, at thickness level of 40 mm, was maintained for at least 120 and 110 minutes respectively.

Results: According to results obtained during research of inert fire-retardant coverings, performed in accordance with procedures ДСТУ-Н-П Б В.1.1-29:2010 “Fire retardant treatment of building constructions. General requirements and methods of control”, it was possible to determine the timescale required to achieve critical temperature levels on the surface of an unheated metal plate, covered by fire retardant aerated concrete tiles at a thickness of 40 mm, in standard temperature fire conditions. The application of this covering to metal structures in building construction was justified.

Keywords: inert fire-retardant covering, fire resistance degree, metal structure, fire-retardant ability, thermo-couple, aerated concrete