Purpose. The research based on FDS modeling aims to identify design parameters influence of the façade firefighting eaves at fire compartment border on the prevention of fire spreading in high-rise buildings.Methods. To calculate the temperature in high-rise building model Pyrosim computer system is used which serves as the user's shell application Fire Dynamics Simulator (FDS). This FDS system uses numerical algorithms to solve the complete Navier-Stokes differential equation system to determine the temperature and other hazardous factors during a fire.Results. This article deals with the results of using the FDS modeling to substantiate fire-fighting eaves design parameters, which are extended beyond the facade and are located at fire compartment border along the perimeter of high-rise buildings with a conventional height of more than 73.5 m. A comparative analysis of eaves' design parameters and their effect on the temperature distribution along the building facade during a possible fire was conducted. Comparative dependences of tempera-ture distribution on building facades were constructed, as well as their heating areas were determined.Scientific novelty. According to national and foreign regulations requirement analytical research and information sources on the of high-rise buildings design, fire safety requirements to the high-rise public buildings facades with a conventional height of more than 73.5 m were scientifically substantiated in terms of the requirements formation for limiting the fire spreading, smoke and building facades exterior constructions heating.Practical value. Obtained data was analyzed as a result of FDS modeling under the same reference conditions to provide a conclusion on facade fire-fighting eaves design parameters effectiveness at fire compartment border and further improvement ways of their construction and fire spread prevention in high-rise buildings.

A method of experimental studies of heat transfer processes between adjacent facilities during fire was developed. Equipment necessary for the experimental studies was determined. A new specimen type for studies was created in order to perform experimental studies. Configuration of the specimen for the studies allows simulation of a building fragment with filler structures which is affected by heat radiation emitted by fire. Points of placement of the specimens for studies relative to the heat flux source when conducting experimental studies were substantiated. It was revealed that height of the specimen installation shall be determined so that the test specimen is located below the flame tip in order to take into account the most severe impact of heat radiation coming from the fire bed and to exclude any possibility of irradiation from the ground surface. It was proposed that the test specimens are placed at the level of the lower edge of the window opening of the building fragment at the distances of2 m,4 mand6 mfrom the building fragment. The sequence of conduction of experimental studies of heat transfer processes between adjacent facilities during fire was developed.

The article considers the processes of release of the openings of relief venting structures based on honeycomb polycarbonate sheets under action of an explosion. The use of honeycomb polycarbonate sheets enables saving transparent fence against destruction, decreasing risks of human traumatism with glass shards, reduce weight of relief venting structures. There were investigated the conditions of the ratio of the opening sizes of the sections of relief venting structures with honeycomb polycarbonate sheets, under which this opening is reliably released to reduce the pressure during the explosion to safe values. A mathematical model was proposed that establishes a relationship between the value of the explosion pressure and the opening size at which the opening of relief structures with honeycomb polycarbonate sheets. The article proposes a calculation method for designing the sections of relief structures with honeycomb polycarbonate sheets using nomograms. The use of developed method lets significantly simplify calculating for design of relief structures with honeycomb polycarbonate sheets.

According to the results of the analysis of methods for determining the critical value of the surface heat flux density for substances and materials, it is established that there is no single approach to determining the critical surface heat flux density for substances and materials today. The development of the method of experimental research of the dependence of the critical surface density of the heat flow from the wind influence as a basis for substantiation of the regularity of change of density of a heat stream from wind influence is an actual scientific task. The article analyzes the current state of the study of the critical surface heat flux density. A method has been developed and experimental studies of the values of the surface heat flux density from wind exposure for substances and materials have been carried out. At the time of experimental research, the regularities of the change in the heat flux density depending on the influence of the amount of airflow introduced into the study space were determined. The purpose of the study is to identify the pattern of changes in the heat flux density of substances and materials depending on the influence of the amount of airflow introduced into the study space. To achieve this goal it is necessary to justify the type and quantity of required test and measuring equipment, as well as the number, shape, and design of sample fragments, justify the methodology of experimental studies of samples under the influence of airflow of different speeds, justify the range of wind speed. The article briefly presents the procedure for conducting experimental research. The obtained data will be used for further research of the flammability of substances and materials. Keywords: critical surface heat flux density, heat flux, heat transfer, radiation heat transfer

To date, there is no statistical base of critical values of surface heat flux density for various substances and materials, in particular those that can be used in the decoration of buildings and technological installations. This article presents conclusions from the analysis of recent studies on this issue, substantiates the reference tabular data of the dependence of wind on the critical surface heat flux density for corrugated cardboard using a full-factor experiment. The authors determined the largest and smallest indicators of significant factors influencing the value of the critical surface heat flux density, namely wind speed (v, m/s) and the set surface heat flux density (q, kW/m2). In the course of the research, a mathematical model was constructed which describes the dependence of wind influence on the critical surface heat flux density for corrugated cardboard. These tables can be used in the future to develop an improved simplified method for predicting the thermal impact of fire on adjacent construction sites, taking into account the impact of wind.