Efecto de un aditivo extraído de la planta <i>Agave americana</i> sobre las propiedades físicas y mecánicas de un yeso

Abstract

SUMMARYPhysical and mechanical properties of a plaster paste added with an organic admixture, of the leaves of Agave americana, were studied. Plastic consistency behavior was evaluated and the water/gypsum(w/g) ratio was determined for each dosage of the admixture. Admixtur eeffect on setting was evaluated too. The chemical transformation of the hemihydrated form to gypsum (dihydrated form) was studied using a novel technique based on a moisture analyzer by halogen light. Flexural and compressive strengths were measured. The results show that ,for the same consistency, accordingly mechanical strengths were improved too. The setting times were increased which would enhance the application time of plaster and would reduce plastic shrinkage, common problems in this type of material. The changes in these physical properties not substantially affect the final mechanical strengths.Keywords: organic admixture; gypsum; physical properties; hydration; halogen moisture analyzer. RESUMENSe estudiaron algunas propiedades físicas y mecánicas de pastas de yeso de construcción adicionadas con un aditivo de origen orgánico, producto de las hojas de la planta Agave americana. Se evaluó el comportamiento plástico de la pasta mediante ensayos de consistencia y se determinó, para cada dosificación, su relación agua/ yeso (a/y). Se evaluó la incidencia del aditivo en los tiempos de fraguado. La transformación química del hemihidrato a yeso dihidrato se estudió mediante una novedosa técnica basada en un analizador de humedad por luz halógena. Se midieron las resistencias mecáni-cas a flexo-tracción y a compresión. Los resultados del estudio muestran que, para una misma consistencia, se mejoran las resistencias mecánicas. Los tiempos de fraguado de la pasta se aumentaron lo que ayudaría mejorar los tiempos de aplicación del yeso y a disminuir las retracciones plásticas. Las modificaciones de estas propiedades físicas no afectan considerablemente las resistencias mecánicas finales.Palabras clave: aditivo orgánico; yeso; propiedades físicas; hidratación; analizador de humedad por luz halógena.

Low-Cost Sensors for Determining the Variation in Interior Moisture Content in Gypsum Composite Materials

“…Several studies have focused on the determination of an adequate water/conglomerate ratio to obtain, in optimal conditions of workability of the material in a fresh state, the best performance in terms of achieving mechanical resistance [9,10]. There are studies, such as the one carried out by Ochoa et al [11], in which by using natural additives extracted from Agave plants, the application times of the gypsum materials were increased without detriment to their mechanical properties, although it is true that most of the commercial additives to accelerate or delay the setting of this type of binding materials are usually composed of chemical compounds designed for this purpose [12,13]. However, this typology of studies on the hardening and setting of gypsum materials have generally focused more on the achievement of new dosages to improve certain properties than on monitoring and continuous monitoring of the setting process.…”