Influence of the facade slope on fire propagation processes on higher floors

Abstract

The study considers the issue of the influence of the structural parameters of the facade on the processes of fire propagation through the external enclosing structures of buildings. The object of the study is the process of temperature changes on the surface of the inclined external enclosing structures of the building due to the action of fire. The study of the influence of the angles of inclination of the facade on the processes of fire propagation and the nature of temperature distributions on the surface of the facade was carried out. During the research, the methodology of experimental tests was used to limit the spread of fire along the facades using an installation that allows you to reproduce the angles of inclination. As the studied fragment of the facade, an external enclosing structure made of non-combustible materials without external cladding was used. Thermocouples were placed on the surface of the facade, which made it possible to obtain temperature data near its surface in real mode throughout the duration of the research. A class 34B model fire source provided a fire load of at least 2,200 MJ/m2 and an average temperature of 800–850 °С throughout the duration of the research. It was found that in the presence of a slope of the facade at an angle of +20°, an increase in temperature near the surface of the studied area by 24–26 % was observed. In the presence of an inclination of the facade at an angle of –20°, a decrease in temperature near the surface of the studied area by up to 55 % was observed. The obtained dependences will make it possible to review the approaches to the existing field methods of fire hazard assessment of facade systems. The practical result of the implementation of the obtained data may be the introduction of changes to building regulations to increase the level of fire protection of facade systems and buildings in general