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Purpose. The article describes constructive and technical solutions for preventing and reducing the consequences of household gas explosions in residential multi-apartment buildings equipped with a fixed gas supply system. Methods. The statistical data on household gas explosions in residential gasified multi-apartment buildings on the territory of Russia have been analyzed. The comparison of existing technical solutions and measures aimed at preventing an emergency explosion and reducing the explosion consequences (gas leak sensor, ventilation system, safety structures of the hinged and swing type) has been carried out. Findings. The data showing the timeliness of this problem due to the significant number of fatalities and large property damage have been obtained. In particular, during the period from 2017 to 2020, 37 explosions of household gas occurred in residential multi-apartment buildings, causing death of 61 people. Despite many positive aspects, the methods being currently used do not provide an adequate level of explosion safety, and therefore the authors see it appropriate to introduce measures aimed at reducing consequences in the event of gas explosion. One of such solutions is the use of a window opening as a safety structure. The main disadvantage, which does not allow us to consider blind glazing as a safety design, is the restriction on the glass thickness (4 mm). In addition, the drawback of using the given construction is low thermal insulation ability and high risk of causing damage to people near the building by glass fragments in the event of an explosion. This disadvantage of modern double-glazed windows can be eliminated by modifying the window frames with the help of special parts or weakened fasteners, which, if excessive pressure occurs, would ensure timely opening of the structure. An example includes safety structures on hinges, which have the ability to rotate these structures when exposed to excessive pressure. Another type of a safety construction is a swing safety design. At a given excess pressure on the working sash, the locking devices, which release the frame rotary sash, are triggered.Research application field. The results of the study can be used in the working out new technical solutions designed to prevent an emergency explosion and reduce the consequences of a potential explosion. Conclusions. The conducted research leads to the conclusion that further work is necessary to study the parameters of internal emergency explosions of household gas in residential buildings under various accident scenarios in order to develop optimal solutions to minimize the consequences of an explosion.

This article experimentally and theoretically demonstrates that the presence of blast-relief openings (windows) equipped with explosion-venting structures (EVS) allows explosive pressure to be reduced to a safe level (2–4 kPa). We provide results of model and full-scale experiments aimed at studying the influence of EVS parameters of blast-relief openings in explosion-hazardous buildings on the intensity of explosive loads. It was demonstrated that the maximum explosive-pressure value inside EVS-equipped buildings depends on the EVS start-to-open pressure, the structure’s response rate (lag), and characteristic dimension of the premises. Thus, each particular building requires individual selection of EVS parameters, which provide a safe level of excessive pressure in case of an explosive accident. This aspect, however, prevents the widespread use of EVS at explosion-hazardous sites. This article offers an modest upgrade of the explosion-venting structure that provides an indoor pressure equal to the EVS start-to-open pressure. The suggested innovation excludes the possibility of a significant increase in explosive pressure due to an EVS response delay. The efficiency of the suggested technical upgrade was proven by numerical experiments and indirectly by experimental studies aimed at exploring the physical processes associated with the opening of EVSs after an explosion accident. The use of upgraded EVSs will allow for provision of a known maximum level of the explosion load should an explosion event occur in an EVS-equipped room.

Introduction. The paper is focused on improving blast resistance of critically important buildings and constructions exposed to a deflagration explosion due to an aircraft (A/C) crash in their vicinity, by improving methods of the explosion effects calculation. The main tasks include: 1. considering the physical processes that occur during an aircraft crash, which causes the formation of a highly explosive cloud; 2. quantifying the parameters affecting explosion loadings; 3. provide insights into modern procedures for calculating effects of a deflagration explosion caused by an A/C crash; 4. giving an example of calculating the loadings on a critically important building or construction in a crash deflagration explosion. Methodology and calculations. The article presents a methodology for calculating the maximum parameters of explosion loadings on buildings and constructions arising from aircraft crash situations. The calculations are performed with the help of author’s and generally accepted methods by the numerical method with the use of MatLab software complex. Results and discussion. As a result of calculations, the proposed methodology allows to obtain: the fuel mass values capable of forming highly explosive mixture; to choose the appropriate scenario for the development of an aircraft crash: an igneous ball or a deflagration explosion of a fuel-air mixture; to determine the time dependence of the fuel vapor concentration in the air; to evaluate the maximum apparent flame front speed; to determine the dynamic parameters of the fireball and the time dependences of the overpressure at points in the space adjacent to the explosion site; to build up a maximum pressure field created by this deflagration explosion; to obtain the explosion loading integral parameters: the maximum and minimum explosion overpressure, the compression phase pulse, the probability of destruction of buildings; to evaluate vibration loading on the building from a deflagration explosion. Conclusion. The methodology presented in the article can be used to calculate the loadings on buildings and structures during a deflagration explosion that occurs when an aircraft crash.

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