Accelerated and natural carbonation of concretes with internal curing and shrinkage/viscosity modifiers

Abstract In many parts of the world, corrosion of reinforcing steel in concrete induced by carbonation of the concrete continues to be a major durability concern. This paper investigates the accelerated and natural carbonation resistance of a set of seven concretes, specifically evaluating the effects of internal curing and/or shrinkage/viscosity modifiers on carbonation resistance. In addition to five different ordinary portland cement (OPC) concretes, two concretes containing 20 % of a Class F fly ash as replacement for cement on a mass basis are also evaluated. For all seven concrete mixtures, a good correlation between accelerated (lab) and natural (field) measured carbonation coefficients is observed. Conversely, there is less correlation observed between the specimens’ carbonation resistance and their respective 28 days compressive strengths, with the mixtures containing the shrinkage/viscosity modifier specifically exhibiting an anomalous behavior of higher carbonation resistance at lower strength levels. For both the accelerated and natural exposures, the lowest carbonation coefficients are obtained for two mixtures, one containing the shrinkage/viscosity modifier added in the mixing water and the other containing a solution of the same admixture used to pre-wet fine lightweight aggregate. Additionally, the fly ash mixtures exhibited a significantly higher carbonation coefficient in both exposures than their corresponding OPC concretes

Memorias del 3er. coloquio de estudios sobre juegos de rol

Aquí se recopilan las ponencias recibidas para ser publicadas en el 4o. Coloquio de estudios sobre juegos de rol (2018), realizado en el Tec de Monterrey campus Santa Fe el 26 y 27 de abril de 2018. Únicamente se publican las ponencias cuyos autores dieron permiso explícito para ello y que facilitaron copia de su trabajo. Los resúmenes de las ponencias pasaron por un proceso de revisión doble ciego para ser admitidas en el coloquio.https://digitalcommons.njit.edu/stemresources/1020/thumbnail.jp

Ciencia Odontológica

Es para los integrantes de la Red de Investigación en Estomatología (RIE) una enorme alegría presentar el primero de una serie de 5 libros sobre casos clínicos, revisiones de la literatura e investigaciones. La RIE está integrada por cuerpos académicos de la Universidad Autónoma del Estado de Hidalgo, Universidad Autónoma del Estado de México, Universidad Autónoma de Campeche y Universidad de Guadalajara