Currently, in Ukraine and abroad for the construction of high-rise buildings and structures using pipe-like structures. Wide application of pipe concrete columns is due to their high carrying capacity at relatively smaller overall dimensions due to the blocking of cracking in concrete by a steel clasp. The advantages of concrete columns should include more simplified conditions of technology of manufacturing and installation on their basis of bearing structures of floor covering. Piping constructions consist of steel shells and concrete core. Since the steel pipe mainly provides the bearing capacity of the concrete column, its failure or reduction of stiffness, which is characteristic of the fire under the influence of its thermal factors, leads to destruction. Investigation of fire resistance of concrete structures, which are not protected by flame retardant coatings, showed that a steel clasp during a fire after 15 minutes is heated to a critical temperature of 500 ° C.The use of flame retardant coatings is an effective method of fire protection of concrete constructions, which prevents the rapid heating of steel welds and provides a normalized fire resistance limit for such structures. In this work, studies were carried out on the effectiveness of fire protection of concrete columns with different types of fire-retardant materials - mineral wool slabs, special flame retardants and flame-retardant coatings. For fire protection mineral wool materials were used ROCKWOOL plates of the series "Conlit SL150". Mineral wool plates "Conlit SL 150" consist of fibers of rocks of a basalt group, they can withstand, without melting, temperature more than 1000 ° С. The silica-based adhesive "Conlit Glue" can withstand temperatures above 900 ° C, has good adhesion when bonding Conlit SL 150 mineral wool slabs with protective structures. From the second type of fire-retardant materials, the fire-proof composition "Naktresk" was chosen on the basis of gypsum. The coating is formed in the process due to hardening of the mixture on protected surfaces. The third type of flame retardant materials is the flame-retardant intumessent coating "Pyro-Safe Flammoplast SP-A2".It has been established that with the use of fire protection systems on the basis of mineral wool plates "Conlit SL150" and fire retardant "Nutresc", the fire resistance class of reinforced concrete columns increases from R 15 to R 180. The fire protection system on the basis of the painted paint "Pyro-Safe Flammoplast SP-A2" »Increases fire resistance from R 15 to R 75

The research subject is finding an engineering solution for V-412 core automatic protection during operation in both steady-state and transient conditions within ICIS using local parameters (i.e. maximum linear power, departure from nucleate boiling ratio). Such engineering solution will be implemented by safety system software-hardware (PTK-Z) on the basis of signals coming from in-core neutron flux detectors, temperature sensors, primary coolant flow and coolant pressure transducers. Calculated survey of possibility to use Kalman filters or corrective filter to eliminate time delay in SPND signals was carried out. The inaccuracy in the method of maximum linear power monitoring was determined. This work shows that the solution was found using the practice of in-core instrumentation, and ICIS designing and operation with improved metrology, reliability and time parameters and using advanced data communication technologies intended for important challenges of the world market, and as a response to standards.

The aim of the work is the development of mathematical models for research that allows to determine the ultimate indicators of the thermal effect on tanks with oil products in a fire. A calculation method was developed to implement the calculation for various scenarios for the development of a fire in a tank with oil. After the calculations, the results of mathematical modeling of the temperature on the walls of the reservoir in the conditions of a fire in neighboring reservoirs in the form of temperature distributions were obtained. Analysis of the temperature distributions showed that the most dangerous scenario is when the fire occurs according to scheme No. 3 in the case of burning an oil torch at a temperature of 1500 K. In each case, the maximum temperature of heating the tank wall is almost unaffected by the oil, which is confirmed by the curves of the maximum temperature curves heating of the reservoir wall, depending on the time of fire impact on adjacent tanks. The maximum temperature of the reservoir wall was determined at the place of its connection with the oil product, it is preserved.

It is experimentally established that air-tested samples of degraded material showed tooth flow that disappears for tests in hydrogen. The main feature inherent in the studied materials are metastable and presence of more or less pronounced time-and temperature-dependent processes of structural relaxation, which reduces the total free energy of a thermodynamic system. The values of fracture toughness minimize the square deviation of experimentally obtained values drift from the theoretical curve corresponding to the exponential relaxation function.

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