RESEARCH OF THE STABILITY OF TRANSPARENT FACADE STRUCTURES UNDER THE INFLUENCE OF HIGH TEMPERATURES

The authors in the scientific work described the results of studies of the stability of translucent structures of high-rise buildings under the influence of high temperatures. The researchers analyzed the mechanism of glass destruction in fire conditions, in particular, studied its reaction to sharp temperature fluctuations, the formation of cracks and subsequent destruction under the influence of thermal loads. The mechanism of fire propagation through window openings on the facade of a high-rise building was studied. The authors emphasize the importance of external factors, such as wind, on the spread of flames on glass facades, as well as the influence of structural features of buildings on the speed and nature of fire development. Using the PyroSim software package, a model of the destruction of transparent structures of high-rise buildings during a fire was developed. The main stages of simulating the destruction of translucent structures are: preparation of the building model; setting fire scenarios; simulation of thermal processes; structural integrity analysis; fire spread calculation. The model allows predicting the behavior of structures. According to the simulation results of a probable fire, it should be noted that a double-glazed unit made of non-tempered glass with a thickness of 6 mm is destroyed by fire 260(±10) seconds before the arrival of fire and rescue units. After the destruction of the double-glazed windows, thermal convection of the heated combustion products and flames occurs vertically, and the glazing of the upper floor located above the fire site is exposed to high temperatures. The maximum temperature, which is recorded using thermocouples, is on average 300-330 ºC, which is quite close to the temperature values of 350 ºC at which there is a high probability of destruction of a double-glazed unit made of untempered glass 6 mm thick. As a result, there is a high probability of fire spreading through the glazing to the floors above.