Non-invasive tests of precast cantilever balcony in OWT-67 system

Abstract

This article presents a non-invasive tests report of precast cantilever balcony support in OWT-67 large-panel system. During field testing, the balcony's reinforced concrete structure was subjected to radiometric analysis in the context of thermal energy distribution as well as from the point of view of mycology - to the possible presence of spores of domestic fungi. The temperature distribution tests carried out by means of the electromagnetic wave detection in the infrared spectrum clearly confirmed the significant losses of thermal energy caused by the effect of the thermal constructional bridge located in the balcony. Mycological diagnosis was carried out using the rapid test of the Mycometer bacterial meter, which allows fluorimetric evaluation of the presence of the enzyme presence in filamentous fungi. In the conducted study, no spores of the house mushroom were found on the inside surface of the Z-type balcony supporting beam as a place where condensation of water vapor may occur. The summary also presents a design solution that allows to eliminate this physical problem.

Efficiency of Different Balcony Slab Modernization Method in Retrofitted Multi-Family Buildings

“…Similar research results were obtained by the second author of this paper for a building erected in a different location in Poland. In the study on non-invasive tests of precast cantilever balcony in the OWT-67 system [39], the average temperature difference was found within the interactions and outside the thermal impact area of the thermal bridge equal to 4K. In the aspect of the internal surface of the external wall, the difference was, on average, 8K on the longitudinal wall in the level of the floor and 3K within the prefabricated "Z" lintel beam.…”

“…The fourth scenario is an authors' alternative solution based on the use of the structural system as in Figure 3d [38,39]. LKBD is characterized by a combined steel and reinforced concrete structure, largely independent of the building structure.…”

“…These issues have also been the research area of interest of the authors of this article. In 2015, Bieranowski [38], after preliminary thermal imaging tests of the precast cantilever balcony support in an OWT-67 large-panel system, subsequently extended by mycological analyses [39], proposed a new alternative wall-balcony connection system: an added selfsupporting external element-the light balcony system (LKBD). Sadowska, based on field research, analyzed the effects of thermal bridges in large-panel buildings before and after thermal modernization, on heat loss [40].…”