Segurança contra incêndio: estudo sobre sistemas de selagem perimetral para compartimentação vertical em fachadas envidraçadas

Abstract

The densification of urban centers, the verticalization of buildings and the increasingly recurrent use of glazed facades puts fire safety in these buildings on debate. Since the glass facades are composed of non-fire resistant elements, it becomes a fragile system and liable to compromise the overall safety of the building and its users. Propagation through the facade can happen both internally, through the space formed between the facade and the building, and externally through leapfrogging. In this way, compartmentalization must be taken into account even in buildings with glazed facades, based on Brazilian technical instructions, which started to adopt 1,20 meter vertical bulkheads together with fireproof sealing systems and horizontal extensions of 0,90 meters as passive protective measures. Unlike other countries, Brazil does not have a specific technical test standard to evaluate the system proposed by the technical instructions, which raises questions about the areal effectiveness of these systems. The present work presents the evaluation of a vertical partitioning system according to Brazilian technical instruction based on the test methodology of ASTM E2307 (ASTM, 2020) and ASTM E2874 (ASTM, 2019), as well as a discussion of the results based on the behavior of fire. Based on the results obtained, it was found that the perimeter seal was able to resist fire until the moment the glass broke next to it and, after breaking, the measured temperatures exceeded the normative limits. The 1,20 meter vertical bulkhead proved to be effective in preventing flames from entering the upper floor, but the heat flux measured at the top of the bulkhead would be capable of igniting materials commonly used as coatings in commercial rooms. Thus, the constructive system proposed by the technical instruction proved to be efficient until the glass broke along with the perimeter sealing, demonstrating the importance of having an appropriate Brazilian technical standard for the development of specific systems that guarantee the vertical compartmentation in the glazed facades.