Efecto del fuego en revestimientos de yeso tradicionales

Abstract

The use of gypsum in architectural heritage has been very varied, being very important its use as a coatingmaterial for other construction elements, since it has important benefits such as transpirability, adherence,warmth sensation and thermal insulation. In addition, gypsum is considered an excellent material whenexposed to fire because it contains water in its chemical composition, which causes a significant amount ofthermal energy to be absorbed by the gypsum, reducing heat transmission to the elements it covers andother nearby materials. Gypsum-based materials are non-combustible and do not release toxic substancesdue to the effect of fire. The amount of mixing water influences the properties of gypsum. The higher thewater/gypsum (w/g) ratio, the higher the workability, the lower the density and the lower the strength. Theinfluence of the w/g ratio on the effect of fire in traditional gypsum plasters is not well known. The objectiveof this work was to analyze the effect of fire on gypsum plasters with different w/g ratios, for whichspecimens with 0.4 w/g and 0.7 w/g ratios were prepared and temperature measurements withthermographic cameras and other instrumental techniques (SEM, XRD and TG) were used to characterizethe microstructure and composition of gypsum plasters subjected to the action of fire. In general, the studiescarried out did not show substantial differences between the studied compositions, although it is true thatthe fire produced a considerable deterioration of the binder.