Проведены исследования теплотехнических свойств образцов строительных конструкций на основе тяжелого бетона, торкрет-бетона и торкрет-фибробетона в условиях углеводородного режима пожара. Показаны преимущества метода лазерной вспышки для определения коэффициентов температуропроводности исследуемых образцов бетонов. С использованием методов синхронного термического анализа и лазерной вспышки выявлены изменения плотности, удельной теплоемкости и температуропроводности в образцах бетонов, а также найдены соответствующие коэффициенты теплопроводности в интервале температур от 25 до 1100 °С. В результате обработки экспериментальных данных методом регрессионного анализа получены эмпирические зависимости для определения вышерассмотренных теплотехнических параметров в выбранном температурном диапазоне. Показано, что полученные результаты могут использоваться для установления пределов огнестойкости строительных конструкций, проектируемых на основе рассматриваемых видов бетонов, в том числе ограждений вертикальных стальных резервуаров для хранения нефти и нефтепродуктов.
Currently, the production of works associated with the construction, repair or restoration of the supporting and enclosing structures of buildings and structures, increasing use is the method of shotcrete. Compared to traditional concrete shotcrete has a high mechanical strength, frost resistance, water resistance, better adhesion to the surface of the structure. Having the ability to successfully work in tension, bending and shock loads in comparison from the traditional concrete, including heavy, shotcrete can be widely used in the construction of a fence of vertical steel tanks for storage of oil and oil products, especially when it is necessary for arrangement of enclosing walls with a visor reflecting the wave, calculated on hydrodynamic loads from the fluid flow, resulting in possible total destruction of the tank. However, to be able to use of shotcrete or fiber-reinforced shotcrete in the construction of fences for tanks, it’s needed to know their behavior in the conditions of a hydrocarbon fire regime, so it is necessary data on thermophysical characteristics such concretes in the temperature range from 25 to 1100 °C. To find thermophysical characteristics of samples of heavy concrete, shotcrete and fiber-reinforced shotcrete in conditions the impact of high temperatures methods of simultaneous thermal analysis and laser flash were used. As result by research there were obtained experimental data on changes of density, specific heat capacity and thermal diffusivity in the samples from the temperature and corresponding calculated dependence of change of coefficient of thermal conductivity. As a result of processing of experimental data by regression analysis, is the empirical dependence for determination of these thermophysical characteristics. By results of processing of experimental data by regression analysis there are obtained the empirical dependences for determination of the above thermophysical characteristics. The research results can be used to determine the fire-resistance of building structures, which are made using the considered types of concrete, including the construction of fences, tanks for storage of oil and oil products.
The authors declare that there are no conflicts of interest present.