Desarrollo de un indicador de calidad percibida sobre el uso de materiales cerámicos en arquitectura mediante análisis de encuestas: estudios preliminares

La finalidad del presente trabajo en proceso, es evaluar si la calidad “objetiva” de los materiales y la percepción “subjetiva” de esa calidad intrínseca determinan el valor de mercado de los inmuebles. En este sentido, se presentan los estudios preliminares realizados hasta el momento para el desarrollo del indicador de calidad percibida del material cerámico en comparación a otros tipos de material. La investigación, compara en su fase inicial los datos muestrales sobre la componente subjetiva basada en la percepción de calidad de los materiales cerámicos percibida por usuarios y expertos, para alcanzarlo se establece en su fase experimental la creación de dos cuestionarios uno para usuarios y otro para técnicos. Consiguiendo, con ello, una metodología de creación e implementación para realizar el cálculo muestral. A continuación se exponen y discuten los análisis preliminares más relevantes encontrados a lo largo del desarrollo de la investigación, que permita posteriormente desarrollar un indicador de calidad percibida. Bajo las premisas expuestas, es propósito del artículo abordar un estudio con una muestra por conglomerados con muestreo aleatorio simple sin reemplazamiento, transversal y anónimo, que se inicia con una creación de encuestas para aplicación directa y personal de un entrevistador, continúa con una investigación descriptiva y termina como estudio comparativo. La muestra para el estudio consistió en 400 encuestas a usuarios y 35 encuestas a técnicos pero debido a estar en fase de implementación de datos se muestran los estudios preliminares procesados hasta el momento 340 encuestas de usuarios sobre las 400 necesarias y 18 encuestas de técnicos sobre las 35 necesarias. El emplazamiento geográfico del estudio se centra en lugares públicos de la provincia de Alicante (Comunidad Valenciana). Se realizaron las encuestas durante la última quincena de Marzo y la primera de Abril de 2009. El análisis estadístico se llevó a cabo en dos fases: descriptivo univariado e inferencial (comparación de medias y proporciones). Los resultados iniciales muestran que el material madera (parquet y tarima) es la mejor opción a emplear tanto para usuarios como para técnicos en las estancias generales, no obstante los técnicos también tienen en muy buena consideración el material cerámico gres porcelánico, y para el resto de estancias prefieren en primer lugar a los materiales cerámicos priorizando sobre el gres seguidos de forma cercana por los materiales pétreos mármol, mármol comercial y granito. Así mismo, al contrastar la estética percibida por los usuarios del material versus la calidad percibida del material por los usuarios apenas se encuentra diferencias estadísticas significativas. Como consecuencia del estudio realizado, se ha podido concluir inicialmente que los usuarios asocian la estética del material a su calidad de forma contraria a la percepción de los técnicos que se basan en las características técnicas. Los hallazgos alcanzados son relevantes por cuanto apoyan empíricamente la posibilidad de creación de un indicador de calidad percibida que permita cuantificar la influencia de la calidad de los mismos; por una parte, y por permitir realizar un cálculo de la estimación más precisa del Valor de Mercado, por la otra.The aim of this work in progress is to assess whether the “objective” quality of the materials and the “subjective” perception of that intrinsic quality determine the market value of properties. Presented here are the preliminary studies conducted to date to develop an indicator of perceived quality of ceramic material in comparison with other materials. In its initial phase, the research compared sample data on the subjective component based on the quality of ceramic materials perceived by users and experts, for which in the experimental stage two questionnaires were produced, one for users and another for technicians. In this way, a creation and implementation methodology was obtained to perform the sample calculation. The most relevant preliminary analyses conducted during the research were then released and discussed in order to produce an indicator of perceived quality. Under this premise, the aim of this paper is to report on sample conglomeration study using simple, transversal and anonymous random sampling, with no replacements, which began by creating surveys to be conducted directly and personally by an interviewer, followed by descriptive analysis to produce a comparative study. The sample for the study consisted of 400 surveys given to users and 35 given to technicians, but as the study is still in the data-implementation phase, the preliminary study has so far processed 340 of the 400 required user surveys, and 18 of the 35 necessary technician surveys. The study was conducted in public places in the province of Alicante (Region of Valencia). The surveys were conducted during the last two weeks of March and the first week of April 2009. The statistical analysis took place in two stages: a univariate descriptive stage and an inferential stage (comparing means and proportions). The initial results show that users and technicians alike consider wood (parquet and platform) to be the best option in general rooms, though technicians also have ceramic porcelain earthenware in high regard, and for other rooms prefer ceramic materials, particularly earthenware, closely followed by stone materials such as marble, commercial marble and granite. Furthermore, practically no statistical differences were found when contrasting how users perceived the aesthetics and quality of the material. As a result of the study, it can be initially concluded that users associate the aesthetics of a material to its quality, in contrast with technicians, who based their perceptions on the technical characteristics of the material. These findings are relevant in that they provide empirical support for the possibility of creating an indicator of perceived quality that can quantify the influence of this quality and produce an accurate estimation of market value.Peer Reviewe

Durability of expanded polystyrene mortars

The influence of the addition of various types and various concentrations of expanded polystyrene foam (both commercial and recycled) on the durability of Portland cement mortars is studied. In particular, the microstructure is studied utilizing the following methods: capillary absorption of water, mercury intrusion porosimetry, impedance spectroscopy and open porosity. In addition, the effects of heat cycles and freeze–thaw cycles on compressive strength are examined. Scanning electron microscopy is used as a complementary technique. An air-entraining agent, water retainer additive and superplasticizer additive are used to improve the workability of mortars. The results show that the presence of expanded polystyrene in mortar results in a decrease in the capillary absorption coefficient. The mercury intrusion porosimetry technique and the equivalent circuits previously used by researchers to interpret impedance spectra of ordinary cementitious materials were found to be inadequate for interpreting the microstructure of mortars with expanded polystyrene. This is due to the polymeric nature as well as the internal porous structure of expanded polystyrene. A slight increase of compressive strength is observed in mortars with expanded polystyrene subjected to heat cycles. The compressive strength of mortars subjected to freeze–thaw cycles likely improves because expanded polystyrene particles absorb part of the pressure of ice crystallization. It is concluded that the durability of mortars improve with the presence of expanded polystyrene, making them viable for more sustainable usage in masonry, stucco and plaster mortars.The authors wish to thank the Spanish Ministry of Science and Innovation and European Union (FEDER) for the BIA2007-61170 project funding, in the framework of which this work has been done, and the FPI scholarship (BES-2009-012166) award to Verónica Ferrándiz Mas which allows her to develop her doctoral thesis, which this present work is part

Use of Impedance Spectroscopy for the Characterization of the Microstructure of Alkali Activated SiMn Slag: Influence of Activator and Time Evolution

The impedance spectroscopy technique has been used to study the microstructure of the binder resulting from the alkaline activation of SiMn slag. Two alkaline activators were used: waterglass and NaOH. Three different concentrations were analysed for both activators: 3.0, 3.5 and 4.0% Na2O for NaOH; and 4.0, 4.5 and 5.0% Na2O for waterglass with a constant SiO2/Na2O ratio of 1.0. The time evolution of the microstructure has been followed up using the non-destructive technique of impedance spectroscopy. This technique has been proved to be effective describing the microstructural changes in alkali activated pastes, and also can help predicting the mechanical behavior of mortars. The use of the resistivity itself seems to be deficient, but the analysis of the electrical parameters calculated from the impedance spectra measured gives a complete idea of the evolution in the material.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. The paper is founded by the research project granted by the Spanish Ministry of Science and Innovation for project funding (PID2020-118322RB-I00) through the “Programa Estatal de I + D + i Orientada a los Retos de la Sociedad” included in the “Plan Estatal de Investigación Científica y Técnica y de Innovación 2017–2020”

Desarrollo de un indicador de calidad percibida sobre el uso de materiales cerámicos en arquitectura mediante análisis de encuestas: estudios preliminares

La finalidad del presente trabajo en proceso, es evaluar si la calidad “objetiva” de los materiales y la percepción “subjetiva” de esa calidad intrínseca determinan el valor de mercado de los inmuebles. En este sentido, se presentan los estudios preliminares realizados hasta el momento para el desarrollo del indicador de calidad percibida del material cerámico en comparación a otros tipos de material. La investigación, compara en su fase inicial los datos muestrales sobre la componente subjetiva basada en la percepción de calidad de los materiales cerámicos percibida por usuarios y expertos, para alcanzarlo se establece en su fase experimental la creación de dos cuestionarios uno para usuarios y otro para técnicos. Consiguiendo, con ello, una metodología de creación e implementación para realizar el cálculo muestral. A continuación se exponen y discuten los análisis preliminares más relevantes encontrados a lo largo del desarrollo de la investigación, que permita posteriormente desarrollar un indicador de calidad percibida. Bajo las premisas expuestas, es propósito del artículo abordar un estudio con una muestra por conglomerados con muestreo aleatorio simple sin reemplazamiento, transversal y anónimo, que se inicia con una creación de encuestas para aplicación directa y personal de un entrevistador, continúa con una investigación descriptiva y termina como estudio comparativo. La muestra para el estudio consistió en 400 encuestas a usuarios y 35 encuestas a técnicos pero debido a estar en fase de implementación de datos se muestran los estudios preliminares procesados hasta el momento 340 encuestas de usuarios sobre las 400 necesarias y 18 encuestas de técnicos sobre las 35 necesarias. El emplazamiento geográfico del estudio se centra en lugares públicos de la provincia de Alicante (Comunidad Valenciana). Se realizaron las encuestas durante la última quincena de Marzo y la primera de Abril de 2009. El análisis estadístico se llevó a cabo en dos fases: descriptivo univariado e inferencial (comparación de medias y proporciones). Los resultados iniciales muestran que el material madera (parquet y tarima) es la mejor opción a emplear tanto para usuarios como para técnicos en las estancias generales, no obstante los técnicos también tienen en muy buena consideración el material cerámico gres porcelánico, y para el resto de estancias prefieren en primer lugar a los materiales cerámicos priorizando sobre el gres seguidos de forma cercana por los materiales pétreos mármol, mármol comercial y granito. Así mismo, al contrastar la estética percibida por los usuarios del material versus la calidad percibida del material por los usuarios apenas se encuentra diferencias estadísticas significativas. Como consecuencia del estudio realizado, se ha podido concluir inicialmente que los usuarios asocian la estética del material a su calidad de forma contraria a la percepción de los técnicos que se basan en las características técnicas. Los hallazgos alcanzados son relevantes por cuanto apoyan empíricamente la posibilidad de creación de un indicador de calidad percibida que permita cuantificar la influencia de la calidad de los mismos; por una parte, y por permitir realizar un cálculo de la estimación más precisa del Valor de Mercado, por la otra.The aim of this work in progress is to assess whether the “objective” quality of the materials and the “subjective” perception of that intrinsic quality determine the market value of properties. Presented here are the preliminary studies conducted to date to develop an indicator of perceived quality of ceramic material in comparison with other materials. In its initial phase, the research compared sample data on the subjective component based on the quality of ceramic materials perceived by users and experts, for which in the experimental stage two questionnaires were produced, one for users and another for technicians. In this way, a creation and implementation methodology was obtained to perform the sample calculation. The most relevant preliminary analyses conducted during the research were then released and discussed in order to produce an indicator of perceived quality. Under this premise, the aim of this paper is to report on sample conglomeration study using simple, transversal and anonymous random sampling, with no replacements, which began by creating surveys to be conducted directly and personally by an interviewer, followed by descriptive analysis to produce a comparative study. The sample for the study consisted of 400 surveys given to users and 35 given to technicians, but as the study is still in the data-implementation phase, the preliminary study has so far processed 340 of the 400 required user surveys, and 18 of the 35 necessary technician surveys. The study was conducted in public places in the province of Alicante (Region of Valencia). The surveys were conducted during the last two weeks of March and the first week of April 2009. The statistical analysis took place in two stages: a univariate descriptive stage and an inferential stage (comparing means and proportions). The initial results show that users and technicians alike consider wood (parquet and platform) to be the best option in general rooms, though technicians also have ceramic porcelain earthenware in high regard, and for other rooms prefer ceramic materials, particularly earthenware, closely followed by stone materials such as marble, commercial marble and granite. Furthermore, practically no statistical differences were found when contrasting how users perceived the aesthetics and quality of the material. As a result of the study, it can be initially concluded that users associate the aesthetics of a material to its quality, in contrast with technicians, who based their perceptions on the technical characteristics of the material. These findings are relevant in that they provide empirical support for the possibility of creating an indicator of perceived quality that can quantify the influence of this quality and produce an accurate estimation of market value.Peer Reviewe

Lightweight mortars containing expanded polystyrene and paper sludge ash

The objective of this research was to develop lightweight cement mortars with good thermal-insulation properties by incorporating expanded polystyrene (EPS) and paper sludge ash (PSA), both of which are problematic waste materials. The mortars formed had low thermal conductivity and low bulk density compared to control samples. Ground EPS produced lower thermal conductivity samples than powdered EPS. Resource efficient mortars containing up to 20% PSA, and 60% of EPS are considered suitable for use in rendering and plastering applications.The authors wish to thank the Spanish Ministry of Science and Innovation and European Union (FEDER) for project funding (BIA2007-61170), and the FPI scholarship (BES-2009-012166) award to Verónica Ferrándiz Mas which allowed her to develop her doctoral thesis. This research was carried out in the Civil and Environmental Engineering Department at Imperial College London, with funding from the Spanish Ministry of Economy and Competitiveness (EEBB-I-12-0574) to support Verónica Ferrándiz Mas

Análisis trabajo no presencial online con Google-Drive en pequeños y grandes grupos en ITE y MSC de Arquitectura (I)

Con este trabajo se ha ensayado la herramienta Google-Drive par utilizarla en el trabajo grupal colaborativo en una asignatura de primer curso del grado de Fundamentos de la Arquitectura y en otra del Master Universitario en Profesorado de Educación Secundaria. Tras la experiencia hemos constatado el desconocimiento en el manejo de este programa por parte del alumnado e incluso del profesorado, y hemos detectado varias dificultades de gestión, y errores en el planteamiento del trabajo, que a partir de la información aportada por este experimento pretendemos subsanar. Hemos concluido el interés de este tipo de herramientas que no requieren la presencia conjunta ni simultánea de los componentes del grupo para la elaboración del trabajo, ni la entrega del documento para la supervisión por parte del profesorado. También hemos descubierto algunas posibilidades que queremos aprovechar para insistir en esta opción de trabajo colaborativo online durante el próximo curso en las asignaturas en que la hemos incorporado este año. Además, pretendemos probarla en la docencia de una nueva asignatura de segundo curso del Grado, en la que se encontrarán el próximo curso los alumnos que se han iniciado este año en la experiencia y dos de las profesoras que han participado

Optimization of the alkali activation conditions of ground granulated SiMn slag

The viability of using a SiMn slag as raw material for the preparation of alkali activated binder has been analysed. The slag has been characterized from the physical, chemical, mineralogical and microstructural point of view. The solution used for the alkali activation process was waterglass, which was prepared by the mix of a sodium silicate solution with sodium hydroxide. The influence of the following design parameters in alkali activated pastes has been studied: %Na2O, SiO2/Na2O ratio and activating solution/slag ratio. All the prepared specimens have been cured under a 100% of relative humidity atmosphere and no additives have been included in the formulations. For the evaluation of the alkali activation process a response surface methodology has been adopted by modelling the obtained results for different control parameters. The proposed experimental methodology consisted of a composite cubic-type experimental design which follows 2nd degree polynomial model. The control parameters of the pastes used in this research have been: workability, compressive strength at 7, 28 and 90 days of curing time, setting times and shrinkage at 50% of relative humidity. The results show that it is possible to valorise the SiMn slag through its use as an alkali activated binder. In general, workability decreases as the %Na2O increases and SiO2/Na2O ratio decreases. Initial setting times ranges from 38 to 263 min depending on the activating solution composition, and workability time decreases for increasing %Na2O. A compressive strength higher than 45 MPa can be achieved by the following activating conditions: 4.0–4.5%Na2O, SiO2/Na2O = 1.00 and activating solution/slag = 0.35–0.375. Shrinkage values of pastes that were cured at 50% of relative humidity ranged from 1.5% to 3.0%.The authors wish to thank the Spanish Ministry of Economy and Competitiveness and European Union (FEDER) for project funding (BIA 2014-58194-R)

Corrosion resistance of steel reinforcements embedded in alkali activated ground granulated SiMn slag mortars

The corrosion process of steel reinforcements embedded in alkali activated SiMn slag mortars was investigated. NaOH and waterglass were used as alkali activators of SiMn slag. The steel reinforced mortars were subjected to two aggressive environments: carbonation and chloride ingress. Carbonation progressed quicker for the binder activated with NaOH, decreasing the rate with the concentration. However, during the corrosion of the steels embedded in the mortars, both activators showed a similar behaviour. Mortars prepared with waterglass exhibited higher chloride migration coefficients, which decreased as the activator concentration increased. In a chloride contaminated ambient, steel embedded in mortars prepared with NaOH offered lower corrosion rate levels and it increased with the activator concentration.The authors wish to thank the Spanish Ministry of Economy and Competitiveness and European Union (FEDER) for project funding (BIA 2014-58194-R)

Corrosion Behavior of Steel Reinforcement in Concrete with Recycled Aggregates, Fly Ash and Spent Cracking Catalyst

The main strategy to reduce the environmental impact of the concrete industry is to reuse the waste materials. This research has considered the combination of cement replacement by industrial by-products, and natural coarse aggregate substitution by recycled aggregate. The aim is to evaluate the behavior of concretes with a reduced impact on the environment by replacing a 50% of cement by industrial by-products (15% of spent fluid catalytic cracking catalyst and 35% of fly ash) and a 100% of natural coarse aggregate by recycled aggregate. The concretes prepared according to these considerations have been tested in terms of mechanical strengths and the protection offered against steel reinforcement corrosion under carbonation attack and chloride-contaminated environments. The proposed concrete combinations reduced the mechanical performance of concretes in terms of elastic modulus, compressive strength, and flexural strength. In addition, an increase in open porosity due to the presence of recycled aggregate was observed, which is coherent with the changes observed in mechanical tests. Regarding corrosion tests, no significant differences were observed in the case of the resistance of these types of concretes under a natural chloride attack. In the case of carbonation attack, although all concretes did not stand the highly aggressive conditions, those concretes with cement replacement behaved worse than Portland cement concretes.Authors thank to University of Alicante and Generalitat Valenciana the financial support given to this research through projects GRE11-27 and GV/2013/021

Mechanical characterization of Portland cement mortars containing petroleum or coal tar

En este artículo se presentan datos experimentales de resistencia a flexión y a compresión de morteros de cemento Portland con adición y sustitución de breas de petróleo y de alquitrán de carbón, que son subproductos de la industria del carbón o del petróleo. Los materiales estudiados son breas de alquitrán de carbón A (BACA) y B (BACB), y dos breas de petróleo (BPP) y (BPT). Los datos demuestran la viabilidad del uso de estas breas en la fabricación de morteros con menores contenidos de cemento, permitiendo diseñar un nuevo material sostenible con el medio ambiente y que contribuya a reducir el impacto ambiental de los materiales de construcción, hecho que permite abrir una nueva vía de valorización de estos subproductos.This article discusses experimental data on the flexural and compressive strength of Portland cement mortars containing additions or cement replacements consisting in petroleum or coal tar, by-products of the oil and coal industries. The materials studied were two coal (BACA and BACB) and two petroleum (BPP and BPT) tars. The results show that it is feasible to use such materials as a partial replacement for cement in mortar manufacture. This should lead to the design of a new sustainable product that will contribute to lowering the environmental impact of construction materials while at the same time opening up an avenue for the re-use of this type of industrial by-products.Generalitat Valenciana (Ref. CTIDIB/2002/164)