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The present paper focuses on the study of mortar samples where expansions with thaumasite formation occur as a consequence of sulphate attack. The samples correspond to a masonry mortar used in a rural construction located in the Spanish province of Toledo made of cement with limestone filler addition CEM II/AL. Composition and microstructure of the mortars have been analysed by means of scanning electron microscopy (SEM) using secondary and backscattered electrons (BSE) and X-ray diffraction (XRD). The results show that aggregates are contaminated with gypsum, which is the source of the sulphates for the internal attack. It seems that thaumasite is formed through an ettringite transformation where aluminium atoms are replaced with silicon atoms by means of a solid solution. The study highlights that thaumasite can be formed in warm weather through an internal sulphate attack due to gypsum contamination of aggregates.

Ante la situación sanitaria provocada por la COVID-19, gran parte de las asignaturas se han tenido que adaptar, de forma urgente y sin el tiempo necesario para analizar rigurosamente la metodología, a la modalidad online o modalidad dual. Esto ha planteado nuevos retos a la hora de la adquisición de competencias del estudiantado, ya que los actuales planes de estudios están diseñados para que cada una de las actividades, ayuden en la adquisición tanto de las competencias transversales como de las específicas. Este problema es más acusado en aquellas asignaturas que plantean un elevado número de horas de la actividad “Prácticas de laboratorio” por ello el interés de plantear un diseño diferente e innovador a la hora de realizar esta actividad en caso de tratarse de modalidad online o dual.

El Grado en Ingeniería Civil, presenta gran dificultad en los alumnos a la hora de superar algunas asignaturas. Debido a que los alumnos repiten matrícula en estas asignaturas, se pueden observar consecuencias como desinterés, estrés académico y familiar. El trascurso ideal sería una matrícula por asignatura. Sin embargo, encontramos bloqueos o dificultades que hacen que los alumnos repitan y vuelvan a matricularse de determinadas materias. Con una base de datos de la Escuela Politécnica superior desde el curso académico 2010-11 al 2017-18, se ha realizado un estudio para determinar el número de convocatorias agotadas medias segregado por sexo, curso y asignatura. Del análisis realizado en las asignaturas de la titulación del Grado en Ingeniería Civil se desprende que el número de convocatorias medias agotadas presenta diferencias con respecto al factor curso académico. Se acentúa en los últimos años posiblemente debido a que las asignaturas de los últimos cursos no tienen todavía los datos consolidados. Además, el número de convocatorias medias agotadas presenta diferencias con respecto al factor asignaturas. Asignaturas de primeros cursos son las que mayor número de convocatorias agota suponiendo un incremento notable en el número de matrículas utilizadas hasta aprobar con el consiguiente incremento de coste y desmotivación.

La ingeniería civil, como disciplina académica, tiene escasa o nula presencia en enseñanza infantil, primaria y secundaria. Sin embargo, otras disciplinas, como la informática o la robótica, sí que han tenido cabida en estos ámbitos. Sumado a esto, encontramos que existe desconocimiento de las capacidades que se pueden desarrollar en estos estudios, encontrándonos con una falta de interés por carreras tecnológicas repercutiendo, de forma directa, en los alumnos que desean cursar las titulaciones, decayendo el número de estudiantes que acceden a esta titulación. La Universidad de Alicante, con el fin de aproximar a los alumnos más jóvenes a la enseñanza superior, organiza habitualmente visitas guiadas y prepara actividades para los más jóvenes. Todo ello con la intención de dar a conocer, desde edades tempranas, la ciencia, la tecnología y la pasión por continuar los estudios en aras de fortalecer la formación de nuestros alumnos. Por ello, esta red pretende adaptar contenidos y preparar actividades para poner en marcha durante las visitas que hacen los estudiantes más jóvenes, a los laboratorios de ingeniería civil.

Currently, political policies aimed at curbing the abuse of natural resources have given rise to a conscientiousness leading to the reevaluation of wastes. Wastes generated from previous mining operations greatly impact the environment, often leaving a legacy of elevated concentrations of heavy metals in the surrounding soil and water. In this study, two types of waste from the mining district of La Union (Spain) were used to study their use as a component of road wearing courses. The physical and mechanical characteristics were determined to identify the optimal content of bitumen, as well as the fatigue resistance using the four-point beam fatigue test, in all the mixtures manufactured. The mine tailings exhibited adequate physical and mechanical properties to be utilized as a coarse aggregate for a wearing course. The results indicate that one of the studied mine tailing forms could be used as a wearing course component, since it has properties similar to a control mix that is typically used in wearing course construction.

Obtaining durable materials that lengthen the service life of constructions and thereby contribute to sustainability requires research into products that improve the durability of cementitious materials under aggressive conditions. This paper studies the effects of sulfuric acid exposure on four mortar types (control mortar, mortar with nanosilica, mortar with zinc stearate, and mortar with an ethyl silicate coating), and evaluates which of them have better performance against the acid attack. After 28 days of curing, the samples were exposed to a sulfuric acid attack by immersing them in a 3% w/w of H2SO4 solution. Physical changes (mass loss, ultrasonic pulse velocity, open porosity, and water absorption), and mechanical changes (compressive strength) were determined after the sulfuric acid exposure. A scanning electron microscope (SEM) was used to characterize the morphology of the surface mortars after the exposure. The control mortar had the highest compressive strength after the acid attack, although of the four types, the zinc stearate mortar showed the lowest percentage of strength loss. The zinc stearate mortar had the lowest mass loss after the acid exposure; moreover, it had the lowest capillary water absorption coefficient (demonstrating its hydrophobic effect) both in a non-aggressive environment and acid attack

Using durable materials is a sustainable solution for extending the lifetime of constructions. The use of crystalline admixtures makes cementitious materials more durable. They plug pores, capillary tracts and microcracks, blocking the entrance of water due to the formation of crystals that prevent the penetration of liquids. The literature has covered the performance of these admixtures on concrete, but studies on mortars are still scarce. The aim of this study is to investigate the effect of an aggressive environment (sulphuric acid solution—3 wt%) on mortars produced with different percentages of a crystalline admixture (1%, 1.5% and 2% by weight of cement content). Physical and mechanical properties were studied after immersing the mortars in a H2SO4 solution for 90 days. It was found that, after a 90-day sulphuric acid exposure, mortars with the crystalline admixture showed greater compressive strength than the control mortar, besides exhibiting lower mass loss. However, the crystalline admixture did not produce any significant effect on the capillary water absorption coefficient. In a nonaggressive environment, and in the short term, the crystalline admixture did not have a significant effect on the compressive strength, the capillary water absorption coefficient or the ultrasonic pulse velocity.

In view of the global sustainable development, it is imperative that supplementary cementing materials (SCM) be used for replacing cement in the concrete industry and several researchers have shown that mineral admixtures can enhance the workability of lightweight aggregate concrete (LWAC) mixture and its strength. In view of the beneficial effects of using SCM in LWAC, this article aims to verify the possible influence of the use of different types of SCM in the segregation phenomenon of LWAC. Three different SCM were studied: Silica Fume (SF), Fly Ash (FA) and Posidonia oceanica Ash (PA). For each SCM, three mixtures were prepared, considering three different percentage substitutions of cement. An image analysis technique was applied to estimate the segregation in each sample. The results show that a substitution of cement by other materials with different grain size, considering a constant water binder ratio, may also result in a variation of the consistency of concrete and the viscosity of the mortar matrix, which may contribute to increase or reduce segregation.

Obtaining durable materials that lengthen the service life of constructions and thereby contribute to sustainability requires research into products that improve the durability of cementitious materials under aggressive conditions. This paper studies the effects of sulfuric acid exposure on four mortar types (control mortar, mortar with nanosilica, mortar with zinc stearate, and mortar with an ethyl silicate coating), and evaluates which of them have better performance against the acid attack. After 28 days of curing, the samples were exposed to a sulfuric acid attack by immersing them in a 3% w/w of H2SO4 solution. Physical changes (mass loss, ultrasonic pulse velocity, open porosity, and water absorption), and mechanical changes (compressive strength) were determined after the sulfuric acid exposure. A scanning electron microscope (SEM) was used to characterize the morphology of the surface mortars after the exposure. The control mortar had the highest compressive strength after the acid attack, although of the four types, the zinc stearate mortar showed the lowest percentage of strength loss. The zinc stearate mortar had the lowest mass loss after the acid exposure; moreover, it had the lowest capillary water absorption coefficient (demonstrating its hydrophobic effect) both in a non-aggressive environment and acid attack.

Using durable materials is a sustainable solution for extending the lifetime of constructions. The use of crystalline admixtures makes cementitious materials more durable. They plug pores, capillary tracts and microcracks, blocking the entrance of water due to the formation of crystals that prevent the penetration of liquids. The literature has covered the performance of these admixtures on concrete, but studies on mortars are still scarce. The aim of this study is to investigate the effect of an aggressive environment (sulphuric acid solution—3 wt%) on mortars produced with different percentages of a crystalline admixture (1%, 1.5% and 2% by weight of cement content). Physical and mechanical properties were studied after immersing the mortars in a H2SO4 solution for 90 days. It was found that, after a 90-day sulphuric acid exposure, mortars with the crystalline admixture showed greater compressive strength than the control mortar, besides exhibiting lower mass loss. However, the crystalline admixture did not produce any significant effect on the capillary water absorption coefficient. In a nonaggressive environment, and in the short term, the crystalline admixture did not have a significant effect on the compressive strength, the capillary water absorption coefficient or the ultrasonic pulse velocity.

Control of water quality of coastal waters is essential to ensure the safety of bathers. Therefore, the current legislation establishes maximum concentration levels of faecal bacteria, in particular Escherichia coli and intestinal Enterococci. After several studies, it is known that there are environmental and physical factors such as the level of urbanization of the beach, sediment type, rainfall, salinity and water temperature, which influence the concentration of these bacteria. However, there are many other factors, such as the morphology of the beach, its orientation relative to waves and the proximity of spills, that can affect the survival of these bacteria and therefore directly influence the water quality in the coastal zone. In this article, 270 beaches between the provinces of Valencia and Granada (Spain) were analysed. It was observed that the local factors that further affect the concentration of faecal bacteria in coastal water are the presence of meadows of Posidonia oceanica, the orientation of the beach with respect to the direction of the most common incident waves and the agricultural discharges in the sea.

Landslides are very complex processes controlled by multiple factors. The knowledge and characterization of these factors is essential for a comprehensive understanding of the mechanisms and kinematics of the instabilities and for an efficient design of corrective measures. The aim of this work is to combine traditional geological and geotechnical techniques with geophysical, remote sensing and forensic techniques for obtaining a whole picture of an active lateral spreading affecting the Finestrat municipality in Alicante, SE Spain. Geomorphological, geotechnical and geophysical techniques (i.e. ground penetrating radar and refraction seismic) have provided essential information about the geometry, structure and petro-physical properties of the slope. A Terrestrial Laser Scanner was used for recognizing the most important sets of discontinuities affecting the rock mass and to evaluate the activity of the landslide slope. Complementarily, a forensic analysis of the building damage completed the available datasets, yielding very useful kinematic information of the landslide. Finally, a sensitivity analysis of the stability of the rock slope has been performed considering both block toppling and block sliding models. Therefore, the multisource analysis performed in this work has allowed the identification and characterization of a complex lateral spreading, highlighting its effectiveness for a comprehensive understanding of this type of landslide.

Las tecnologías de la información y comunicación (TIC) contribuyen al acceso de la enseñanza e igualdad en el aprendizaje. La incorporación de las TIC en enseñanza superior exige una planificación previa de objetivos para los retos que nos proponemos. El uso de este tipo de enseñanza está demostrado que motiva y estimula ya que el aprendizaje puede ocurrir en cualquier lugar y momento. Partiendo de estas afirmaciones, y con las posibilidades que nos brindan las nuevas plataformas y redes sociales a los que estamos cada día más arraigados, una fuente de motivación para nuestros alumnos puede ser llevada a cabo por parte del profesorado, mostrando las realidades técnicas y prácticas de nuestras asignaturas en los ámbitos en los que navegan nuestros alumnos. Una plataforma con una gran aceptación, difusión y repercusión es Twitter. Así mismo, una de las grandes dudas que se plantea el alumno es cómo afrontar el TFG. Qué documentos tiene que presentar, qué formato, fuentes de información, fechas, etc. Cada alumno tiene un tutor diferente por lo que no todos brindan esa información por igual. Se pretende unificar y homogeneizar todo el material en la plataforma CI2 de la Biblioteca de la Universidad de Alicante.

Everyone is aware of the special relationship that man has with the coast; from the beginning of man- kind, humans have been attracted to the littoral zone for the construction of settlements and the use of its resources. Subsequently, humans have evolved, leaving an increasingly large footprint on this medium. Hence, there is a need to deepen our knowledge to protect against the threat that we ourselves pose. Coastal regression mainly due to the lack of sediment is a global problem. The environmental, economic and social interest makes the study of coastal regression a major problem in the institutions. This article places the study area in Denia (Alicante, Spain). In this population, for some time, there has been concern about the effect on the beaches of the sharp erosion of the coastline. The Marineta Cassiana beach has been chosen for this study because of its special location and the set of elements of the environment. Thus, with respect to the beach study, it is observed that the land beside it is a fully urbanized area, which has suffered due to the pressure of development in this area since 1956, limited as it is by background mountains. Therefore, this study encompasses different aspects of the regression of the coast. To this end, a study of the historical evolution of the beach since 1956 has been carried out. The hydrological modelling of river basins discharging to the beach and their changes due to the alteration of the landscape has been carried out, using dynamics and morphological characterization of the area and an analysis of the erosion of these basins. Also, the historical evolution of the surf on the beach, as well as changes in the morphology of the coast, which have influenced the marine climate, have been taken into account.

The development of biocomposites has valorized some natural products related to natural processes or crop industries. In this regard, Posidonia oceanica is a marine phanerogam typical of Mediterranean coasts, in which due to tourism industry a lot of resources are destined to remove and treat Posidonia residues left on beaches. In this work an alternative to recycle this natural waste has been studied. Biocomposites with Posidonia and pine-wood particles were tested as an alternative to structural wood particle boards used in construction. Different substitution ratios (pine by Posidonia) were prepared in two different polymeric matrices and their mechanical properties were tested. Particles boards made in 75% Posidonia oceanica and 25% wood particles and a MDI matrix (20–30% by fibers mass) showed the best strength and stiffness to density ratios. This stiffness was even similar to a panel made totally in wood and MDI in the same dosage, i.e. 75% of pine fibers could be replaced by Posidonia with low stiffness loss.

El Trabajo final de Grado se concibe, desde el punto de vista académico, como una asignatura obligatoria de 12 créditos ECTS. Se imparte en el segundo semestre de cuarto curso. La elaboración de este trabajo requiere un seguimiento y tutela continuada de docentes, con experiencia en la elaboración de proyectos de este tipo, y finaliza con la exposición y defensa frente a un tribunal. Tal y como indica la Guía Docente de la asignatura, el TFG consiste en la realización de un proyecto de natura profesional dentro del ámbito de la Ingeniería Civil. Este proyecto de debe sintetizar e integrar las diferentes competencias que han sido adquiridas durante los estudios del Grado en Ingeniería Civil. Resumen entre 150 y 200 palabras sobre el contenido del trabajo. En esta titulación se forman grupos de 10-15 estudiantes a cargo de un profesor que realiza el seguimiento y tiene una docencia reglada de 30 horas para el seguimiento de los trabajos. No obstante, el tutor suele invertir del orden de 7 horas en la tutorización personalizada del alumno.

Mathematical models used for the understanding of coastal seabed morphology play a key role in beach nourishment projects. These projects have become the fundamental strategy for coastal maintenance during the last few years. Accordingly, the accuracy of these models is vital to optimize the costs of coastal regeneration projects. Planning of such interventions requires methodologies that do not generate uncertainties in their interpretation. A study and comparison of mathematical simulation models of the coastline is carried out in this paper, as well as elements that are part of the model that are a source of uncertainty. The equilibrium profile (EP) and the offshore limit corresponding to the depth of closure (DoC) have been analyzed taking into account different timescale ranges. The results have thus been compared using data sets from three different periods which are identified as present, past and future. Accuracy in data collection for the beach profiles and the definition of the median grain size calculation using collected samples are the two main factors that have been taken into account in this paper. These data can generate high uncertainties and can produce a lack of accuracy in nourishment projects. Together they can generate excessive costs due to possible excess or shortage of sand used for the nourishment. The main goal of this paper is the development of a new methodology to increase the accuracy of the existing equilibrium beach profile models, providing an improvement to the inputs used in such models and in the fitting of the formulae used to obtain seabed shape. This new methodology has been applied and tested on Valencia's beaches.

In this article, a methodology is presented for the classification of gravel beaches, which can be applied internationally. Such beaches' defence against the energy of incoming water flow is due to their steep slopes and the high permeability of infiltration, but that defence is reduced with increasing sand fraction. The objective of this research was to understand the variables involved in the formation of gravel beaches, to classify them according to the distribution and position of sediment along the transversal profile, and to obtain a discriminant function. To apply the methodology, 34 gravel beaches in the province of Alicante, Spain, were first classified visually into five different types: Type 1: Sand and gravel beaches, Type 2: Sand and gravel separated beaches, Type 3: Gravel and sand beaches, Type 4: Gravel and sand separated beaches, and Type 5: Pure gravel beaches. In addition, a major study was performed to reduce the number of variables because one of the concerns was to find the variables that characterize and classify the beaches. Thus, the 45 variables, grouped according to material characteristics, wave, boundary conditions, and geometry of the beach, were first reduced to 25 by making comparisons among them and the type of beach and were finally reduced to 14 using the discriminant method. Note the use of the important variable Posidonia oceanica in the Mediterranean area, which, because of the changes produced in the swell, was actively involved in the classification. Finally, the discriminant function obtained was validated.

In this study, the behavior of bituminous mixes made with sewage sludge ash (SSA) as mineral filler was investigated. The behavior of these mixes was evaluated with the Cantabro, indirect tensile strength, water sensitivity, permanent deformation, and resilient modulus tests. The results show that SSA waste may be used in bituminous mixes at approximately 2–3% weight percent, maintaining adequate levels of cohesion and adhesion in the mixtures, which is comparable to mixtures made with active fillers such as hydrated lime and cement. Moreover, its use does not increase permanent deformations. However, the resilient modulus test gave slightly lower results for mixes made with SSA than for mixtures made with other fillers. It may be concluded that SSA waste may be used as a filler for bituminous mixes with better results than for mixes made with limestone fillers and with similar results for mixes made with other fillers such as hydrated lime and cement.

In this work, particleboards manufactured with Oceanic Posidonia waste and bonded with cement are investigated. The particleboards are made with 3/1.5/0.5 parts of cement per part of Posidonia waste. The physical properties of bulk density, swelling, surface absorption, and dimensional changes due to relative humidity as well as the mechanical properties of modulus of elasticity, bending strength, surface soundness, perpendicular tensile strength and impact resistance are studied. In terms of the above properties, the best results were obtained for particleboards with high cement content and when the waste “leaves” are treated (crushed) before board fabrication, due to internal changes to the board structure under these conditions. Based on the results of fire tests, the particleboard is non-flammable without any fire-resistant treatment., En esta investigación se han diseñado y fabricado tableros con residuo de Posidonia Oceánica y cemento. Los tableros se han fabricado con 3/1.5/0.5 partes de cemento por cada parte de Posidonia estudiándose sus propiedades físicas (densidad, hinchazón, absorción superficial, variaciones dimensionales por humedad) y mecánicas (módulo de elasticidad, resistencia a flexión, al arranque de superficie, al arranque de tornillo, a la tracción perpendicular y al choque). Se observa una mejora de los resultados de resistencia mecánica con el incremento de la cantidad de cemento y si la hoja del residuo es previamente tratada ya que proporciona una mejor estructura interna en el tablero. Además, tras los ensayos de reacción al fuego, se observa que el material es no inflamable sin ningún tipo de tratamiento ignifugante.

The present study explored the technological feasibility of re-using sewage sludge ash (SSA) as a Portland cement replacement in commercially manufactured pre cast concrete blocks. The blocks analysed were made to the guidelines laid down in Spain’s National Plan for Waste Water Treatment Plant Sludge, 2001–2006, and European Union specifications (CE marking) for such products. Performance was compared in three families of blocks, with 0, 10 and 20% SSA. The findings proved that SSA is apt for pre cast concrete block manufacture and that, in addition to the economic and environmental benefits afforded, its use would improve certain of the properties of conventional block., El objetivo de esta investigación es estudiar el uso potencial de las cenizas de lodos de depuradora (CLD), como sustitución del cemento Portland en bloques de hormigón prefabricados, de forma que se pueda lograr una revalorización de este material de desecho mediante este procedimiento. La metodología utilizada en este trabajo se rige por las directrices del Plan Nacional Español de Lodos de Aguas Residuales de 2001–2006, y por las exigencias del Consejo Europeo (marcado CE), que es obligatorio para este tipo de productos. Se han utilizado dos niveles de sustitución de cemento (10% y 20%), y todos los resultados han sido referidos a las muestras control. Los resultados obtenidos muestran que es posible utilizar una sustitución parcial del cemento por CLD, en la fabricación de bloques de hormigón prefabricados, y por lo tanto, se pueden conseguir beneficios económicos y ambientales, así como la mejora de una serie de propiedades.

This study analyzes the viability of using sewage sludge ash (SSA) as a raw material in the composition of concrete, with a similar dosage to when it is used to manufacture blocks, therefore, with dry consistency given the type of the industrial process of these precast. These ashes are a serious problem, so their valorization in a sector like construction, with a high demand of resources, would be a great advantage from an economic and environmental perspective. A scale with the percentages of addition of ash in relation to cement (5, 10, 15 and 20%) was designed and the replacement of sand by this material, as well as the addition of an inert material such as marble dust. For a better understanding about how these mixtures behave in other cementitious systems, thermogravimetric analysis were performed on pastes with curing ages of 7, 28 and 90 d, and physical and mechanical tests on mortars cured for 28 and 90 d. It was proved that the addition of SSA in concrete used for manufacturing blocks cured for 28 d provided densities and resistances similar to the control sample (without SSA) and significantly reduces the water absorption. The replacement of sand by the mineral addition significantly improves the parameters mentioned above.

Binary and ternary combinations of sewage sludge ash (SSA) with marble dust (MD), fly ash (FA) and rice husk ash (RHA) as replacement in Portland cement pastes, were assessed. Several tests were carried out at different curing ages: thermogravimetry, density, water absorption, ultrasonic pulse velocity and mechanical strengths. Pozzolanic effects of the mineral admixtures, densities similar to control sample and improved absorptions when combining waste materials were identified. In general, the compressive strength reaches or exceeds the cement strength class, and blending SSA, FA and RHA (30% cement replacement) increase of strength by 9%, compared to the control sample, was achieved.

Este trabajo recoge el desarrollo conceptual, de proyecto, construcción y de ejecución de un conjunto de siete esculturas disenadas para actuar como contenedores de otras obras de arte (17 cuadros) realizadas por el artista Jesús Soler. Este conjunto escultórico basa su mensaje en la sostenibidad y el reciclaje. Presenta, como condiciones de contorno fundamentales, la capacidad de ser montado y desmontado sin necesidad de anclar al terreno, durabilidad y protección de las obras frente a agentes meteorológicos y todo ello transmitiendo por sí mismas un mensaje medioambiental. Se describe en el documento la geometría y proporciones basadas en el “Modulor” de Le Corbusier y, por consiguiente, en la sección áurea, así como todas las técnicas constructivas aplicadas para el correcto diseno de cada obra: sistemas de encofrado, hormigones con áridos reciclados, marcos de acero corten, anclajes, etc. Finalmente se describe el primer proceso de montaje de esta obra itinerante, en el Parque del Retiro de Madrid., This paper shows the conceptual development, project, constructive and execution processes of a group of seven sculptures designed to act as containers of other art works carried out by the Spanish artist Jesús Soler. This sculptural group bases its message on the sustainability and the recycling of materials. Its fundamental boundary conditions are the capacity to be mounted and dismounted without any anchorage to the soil, durability and protection of the art work in front of meteorological agents. The sculptural group transmits by itself an environmental message. This paper describes the geometry and proportions, based on the “Le Corbusier Modulor” and the golden section, as well as all the constructive techniques applied for the correct design of each sculpture: formwork systems, concrete with recycled arid, corten steel frames, anchorages, etc. Finally the first assembly process of this itinerant sculptural work is described; it is mounted in the Parque del Retiro in the city of Madrid (Spain).

Prácticas de laboratorio de la asignatura de Materiales de Construcción de 2º curso de Ingeniería Técnica de Obras Públicas.