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© 2018 The Authors, published by EDP Sciences. Pore structure characterization is a key aspect when studying the durability of cementitious materials. When supplementary cementitious materials (SCMs) are used changes in pore structure are expected, and the complexity of its analysis is increased. The purpose of this paper is to describe the pore structure variation of mortars with two types of SCMs: natural pozzolan from volcanic origin (NP), and limestone powder (LP). We tested mixes with cement replacements (in weight) of 20 % and 40% by NP, and 10 % and 20% by LP. To analyse the pore structure, two widely accepted and complementary techniques were applied: dynamic water vapour sorption (DVS) and mercury intrusion porosimetry (MIP). With the DVS data, the Barret-Joyner-Halenda (BJH) model was used for pore size distribution assessment. Calculations with the Dubinin-Radushkevich (DR) model were also made for the smallest pore size range. Tests were performed at 28 and 90 days. MIP and DVS allowed evaluating the effect of the studied SCMs on different pore size ranges. Both techniques provided comprehensive information over a wide range of pore sizes. The mix with 40 % of NP had the best evolution, showing a significant volume decrease in the mesopore range. ispartof: INTERNATIONAL CONFERENCE ON CONCRETE REPAIR, REHABILITATION AND RETROFITTING (ICCRRR 2018) vol:199 ispartof: 5th International Conference on Concrete Repair, Rehabilitation and Retrofitting (ICCRRR) location:Cape Town, SOUTH AFRICA date:19 Nov - 21 Nov 2018 status: published

For the current research topic general objective assess chemical risks hexane, heptane and octane in an effort to prove the hypothesis under the following parameters: Chemical hazards hexane, heptane and octane affect the health of workers terminal area offices Ambato clean products of EP Petroecuador. Research methods were used hypothetical - deductive according to specific objectives. the dispatch areas Terminal Products Clean Ambato at high risk chemical hexane, heptane and octane thus resulting in a dose of 1,68 which it is a dangerous dose health: With the applied methods such as results found workers in addition to this the survey where most respondents stress that if they suffer discomfort in his health from exposure to chemicals such as hexane, heptane and octane with what proved the hypothesis argues. From the results we found was raised design cabins gas extractors allowing performance tests and succeeded in reducing pollution by about 50%, value obtained through measurements made after built the cabins, which meant that the dose concentration of these chemicals (hexane, heptane and octane) are within the allowed limit TWA TLV. Para el presente tema de investigación se plantea como objetivo general evaluar los riesgos químicos por hexano, heptano y octano con el afán de demostrar la hipótesis bajo los siguientes parámetros: Los riesgos químicos por hexano, heptano y octano inciden en la salud de los trabajadores del área de despachos del Terminal de Productos Limpios Ambato de EP- Petroecuador. Se utilizaron métodos de investigación hipotético – deductivo según los objetivos específicos planteados. Con los métodos aplicados se encontraron resultados tales como: las áreas de despacho del Terminal de Productos Limpios Ambato presentan alto riesgo químico por hexano, heptano y octano, dando como resultado una dosis de 1,68 la cual es una dosis peligrosa para la salud de los trabajadores, además a esto se argumenta la encuesta realizada donde la mayoría de los encuestados resaltan que si sufren molestias en su salud por causa de la exposición a las sustancias químicas tales como hexano, heptano y octano con lo que se demostró la hipótesis. A partir de los resultados encontrados se planteó diseñar cabinas con extractores de gases, lo que permitió realizar pruebas de funcionamiento y se logró reducir el aire contaminado en aproximadamente un 50%, valor obtenido a través de mediciones realizadas luego de construidas las cabinas, lo que implico que la dosis de concentración de estas sustancias químicas (Hexano, heptano, octano) están dentro del límite permitido TLV TWA.

This research makes a noise study in Concrete Guayllabamba Company Herdoiza Crespo Constructions S.A. in order to develop a Noise Prevention System. First we identify the presence of Occupational Ear pathology in workers with greater exposure to industrial noise using labor audiometry. Then identify Risk Factors most affected using qualitative matrix that considers the probability and consequence. To encourage this investigation a study of sound pressure level in terms of work in Concrete Company is performed. The study uses the engineering method UNE-EN ISO 9612: 2009 containing all jobs exposure. These trials included the determination of the level of SPL equivalent in 1/1 octave band according to the corresponding show and then determine the dose and the expanded level uncertainty with a confidence level of 95%. The hypothesis tested in this study is that noise affects Occupational Ear pathology for the execution of work in the Concrete Company. The deep of industrial noise determined that the risk factor partially intolerable for this system of work was the noise. The Noise Prevention System product of this work identified some control measures to the aspects set as high risk in terms of source controls in the middle and at the receiver. El presente trabajo de investigación realiza un estudio de ruido en la Planta de Hormigón Guayllabamba de la Compañía Herdoiza Crespo Construcciones S.A. para desarrollar un Sistema de Prevención de Ruido. Empieza identificando la presencia de Otopatías Ocupacionales en los trabajadores con mayor exposición a Ruido Industrial utilizando audiometrías laborales. Luego se significa los Factores de Riesgos de mayor afectación usando la Matriz cualitativa que considera la probabilidad y consecuencia. Para profundizar la investigación se realiza un estudio del Nivel de Presión Sonora en función de los puestos de trabajo de la Planta de Hormigón. El estudio usa el método de ingeniería según la norma UNE-EN ISO 9612: 2009 comprendiendo a todos los puestos con exposición. Dichos ensayos alcanzaron la determinación del nivel de Presión Sonora equivalente en banda de octava 1/1 según el muestreo correspondiente para luego determinar la dosis y el nivel de incertidumbre expandida con un nivel de confianza del 95%. La hipótesis que se prueba en este estudio es que el ruido incide en las otopatías ocupacionales por la ejecución del trabajo en la Planta de Hormigón. El estudio de ruido industrial a profundidad determinó que el factor de riesgo intolerable parcialmente para este sistema de trabajo analizado es el ruido. El Sistema de Prevención de Ruido producto de este trabajo determinó medidas de control a los aspectos establecidos com

After several years of research in the Magnel Laboratory (Belgium) to obtain concrete with self-healing properties, the most promising mechanisms were tested on a larger scale. Instead of small mortar samples with self-healing properties, real-scale self-healing concrete beams (150 mm × 250 mm × 3000 mm) were made and the efficiency of autonomous crack repair was evaluated over time after loading the beams in four-point bending. In addition to a reference beam without self-healing properties, a beam with encapsulated polyurethane and a beam containing superabsorbent polymers were investigated. While for the beam with polyurethane, crack repair is obtained as the healing agent is released as soon as cracks damage the embedded capsules, the superabsorbent polymers absorb water which intrudes into the cracks, immediately blocking the crack through swelling and later on by continued hydration and precipitation of calcite. The efficiency of both self-healing approaches was compared by measuring the reduction in water ingress into the cracks and by measuring the crack width reduction over time.

The stress-strain behaviour of glass textile reinforced cementitious composites in tension is highly non- linear. Focusing at the multiple cracking stage, cracks are initiate and propagate across the cementitious matrix. The opening of these cracks is influenced by the volume fraction of reinforcement, the strength of the matrix, the geometry of the specimen, the debonding phenomena at the matrix- fibre interface and several other parameters. Investigation of the strain profile and the crack width, on this phase of tensile loading, is done in two different composites: E- glass textile reinforced inorganic phosphate cements and AR- glass textile reinforced fine- grained cements. In both cases, Digital Image Correlation (DIC) is used to visualize the crack pattern and the strain distribution. This initial research for a system with low crack width (lower than 100?m) under tension would be used for the future application of self- healing mechanism on cementitious composites.

The present research work, a study of psychosocial risk factors they are exposed to teachers of the Pontifical Catholic University of Ecuador Ambato Headquarters to develop an interactive module and prevent diseases of psychosomatic origin. He began making identification of risk factors with greater presence with an analysis of risk factors using qualitative Matrix triple criterion (likelihood, severity and vulnerability) recommended by the Ecuadorian Ministry of Labour Relations, then performed the evaluation of Psychosocial Risk Factors Questionnaire ISTAS applying 21 to 87 teachers, thus identifying the prevalence of adverse exposure the following stressors: available time control, cognitive psychological demands, uncertainty about the future, and the possibility of social relationship, then set the relationship between the presence of stressors in the presence of psychosomatic diseases reference to the records of morbidity PUCESA medical department in 2011, determining the most common diseases of circulatory, gastrointestinal and nervous system, featuring up to 30 % attending between March and December 2011, in order to prevent these diseases was determined and control measures established prevention aspects as unfavorable factors in proposing intervention in administrative organization as: time management, professional autonomy, communication styles and systems of conflict regulation and intervention in the individual developing general techniques, cognitive techniques, physiological techniques and behavioral techniques to reduce stress levels. El presente trabajo de investigación realizó un estudio de Factores de Riesgo Psicosocial a los que están expuestos los docentes de la Pontificia Universidad Católica del Ecuador Sede Ambato para desarrollar un Módulo Interactivo y prevenir enfermedades de origen Psicosomático. Se empezó realizando una identificación de los factores de riesgo con mayor presencia con un análisis de Factores de Riesgo usando la Matriz cualitativa de triple criterio (Probabilidad, Gravedad y Vulnerabilidad) recomendada por el Ministerio de Relaciones laborales Ecuatoriano, luego se realizó la evaluación de los Factores de Riesgo Psicosocial aplicando el Cuestionario ISTAS 21 a los 87 docentes, identificando así la prevalencia de exposición desfavorable los siguientes estresores: control de tiempos a disposición, exigencias psicológicas cognitivas, inseguridad sobre el futuro, y la posibilidad de relación social, posteriormente se estableció la relación entre la presencia de estresores con la presencia de enfermedades de origen psicosomático tomando como referencia los registros de morbilidad del departamento médico de la PUCESA del año 2011, determinando las enfermedades más frecuentes las circulatorias, gastrointestinales y del sistema nervioso, presentando hasta un 30% de presencia entre los meses de marzo a diciembre del 2011, con la finalidad de prevenir estas enfermedades se determinó medidas de control y prevención a los aspectos establecidos como factores más desfavorables proponiendo la intervención en la organización en aspectos administrativos como: gestión del tiempo, autonomía profesional, estilos de comunicación y sistemas de regulación de conflictos e intervención en el individuo desarrollando técnicas generales, técnicas cognitivas, técnicas fisiológicas y técnicas conductuales para disminuir los niveles de estrés