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Concrete and Portland cement-based products are the most widely used materials in the construction industry. According to the Global Cement and Concrete Association (GCCA), 14 billion cubic meters of concrete are consumed worldwide every year. Knowledge of their properties is essential to ensure the quality of concrete products and structures. Knowing the evolution of certain parameters related to their durability makes it possible to prevent situations that affect compliance with quality requirements. Thanks to advances in IoT (Internet of Things) technologies, it is possible to know the evolution of these parameters in real time. The following work pursues the development and application of a prototype to monitor the setting time of concrete. This equipment provides real-time measurements, taking advantage of the Internet of Things (IoT) technology, allowing effective monitoring of the thermal behavior of concrete during its setting process. By measuring the temperature of the process and evaluating the resistance acquired during the setting time, we can correlate these two parameters, thus ensuring their correct evolution and allowing quick action to avoid future problems. For the development of this work, temperature measurements were made during the setting of 12 concrete specimens corresponding to four different mixtures (two types of cement with and without additives), assessed at three setting ages (28, 90, and 180 days). Through detailed experimental tests, the sensor was accurately and reliably validated, showing its ability to detect temperature changes, indicating the initial and final setting time. In addition, it was observed that the integration of the DS18B20 sensor does not compromise the structural properties of the concrete. The prototype’s cost-effectiveness, efficiency, and easy installation make it a valuable tool for construction professionals, offering an innovative solution to ensure the quality and durability of the concrete. This breakthro

Several gold deposits in the eastern region of Cuba are genetically related to the island arc- and the ophiolitic complex formation. These have been studied and exploited since the time of the Spanish colonization in the mid-sixteenth century. These deposits belong to the Aguas Claras-Guajabales mineral field in the Holguín Province (Cuba) and lie in an elongated zone approximately 15 km in length. The object of this work is to make a methodical, detailed, and chronological review of the geological and mining work carried out in this region, as well as highlight the degree of the previously achieved studies. To realize this, an extensive bibliographic review of all available data, including published reports and articles, as well as unpublished material, was carried out. Moreover, ore mineralogy and petrography were reviewed by thin section analyses from samples from these deposits by petrographic and scanning electron microscopy. The results obtained from this study highlight that the gold mineralization in that area is closely linked to metasomatic processes produced by the circulation of hydrothermal fluids that affected the different volcanic and ultramafic rocks. This study shows that the highest gold contents observed are controlled by the contacts between the different host lithologies with high rheological contrasts. The presence of different alteration styles such as serpentinization, listvenitization, rodingitization, and propylitization have played a primary role in the deposition of gold during mineralization processes. This work could be a very useful exploration guide for future research in this region, as it provides a useful and practical compilation of the characteristics of the mineralization and alteration styles, as well as a precise indication of the spatial position, thicknesses, and contents of the gold-rich horizons.

The eruption of the Cumbre Vieja volcano on 19 September 2021, resulted in the deposition of large quantities of volcanic ash (VA), causing a great impact on the citizens. This work aims to study the properties of this volcanic ash as pozzolanic raw materials to establish their potential use in the development of sustainable cement. Results of chemical and technical characterization are presented. To achieve this goal, Ordinary Portland Cement (OPC) was replaced with standardized percentages of OPC/VA: 10, 25, and 40%. Characterization studies were carried out using chemical analysis of X-ray fluorescence (XRF), chemical quality analysis (QCA), pozzolanicity test (PT) at 8 and 15 days, as well as determining the mechanical strength (MS) at 7, 28, and 90 days. The results obtained by XRF and QCA established that the chemical composition of the VA corresponds to that of the natural pozzolan typical of pyroclastic genesis. The PT test showed that the analyzed samples have a marked pozzolanic nature, both at 8 and 15 days, showing a significant increase in their hydraulic reactivity. Likewise, the MS tests confirmed a continuous increase in mechanical compressive strength, which increased significantly from 7 to 90 days of curing, reaching more than 58 MPa. On the other hand, mechanical tests showed that the three types of dosages used OPC/VA:10, 25, and 40% were equally effective, with OPC/VA formulations: 10–25% being the most effective. The results obtained in this research could be used by local industries as a guide for the correct use of the volcanic materials of this island, both for the manufacture of construction materials, such as aggregates, and to produce pozzolanic cement with low CO2 emissions, thus having a positive impact on the environment. Finally, the great natural availability of natural VAs in the surrounding areas of La Palma could cover part of the needs for materials used in the construction and restoration of houses and infrastructures damaged d

The speed at which climate change is happening is leading to a demand for new pozzolanic materials that improve the quality of cements and, at the same time, limit the emission of greenhouse gases into the atmosphere. The main objective of this work is the detailed characterization of an ignimbrite sample (IGNS) to demonstrate its effectiveness as a natural pozzolan. To meet this objective, a series of tests were carried out. In the first stage, mineral and chemical analyses were performed, such as petrographic analysis by thin section (TSP), X-ray diffraction (XRD), oriented aggregate (OA), scanning electron microscopy (SEM) and X-ray fluorescence (XRF). In the second stage, the following technical tests were carried out: chemical quality analysis (QCA), pozzolanicity test (PT) and mechanical compressive strength (MS) at 7, 28 and 90 days, using mortar specimens with ignimbrite/cement formulation (IGNS/PC): 10, 25 and 40% to establish the pozzolanic nature of the ignimbrite. The results of the mineral and chemical analyses showed that the sample has a complex mineralogical constitution, consisting of biotite mica, potassium feldspar, plagioclase, smectite (montmorillonite), quartz, volcanic glass, iron, titanium and manganese oxides, chlorite and chlorapatite. On the other hand, the technological tests revealed the pozzolanic nature of the sample, as well as visible increases in the mechanical compressive strengths in the three proportions, the most effective being IGNS/PC:10% and IGNS/PC:25% at 7, 28 and 90 days of setting. The results obtained could be applied in the formulation of new pozzolanic cements with ignimbrite as a natural pozzolanic aggregate.

The object of this work is to study and characterize diatomites from the southeast of the Iberian Peninsula to establish their character and quality as natural pozzolans. This research carried out a morphological and chemical characterization study of the samples using SEM and XRF. Subsequently, the physical properties of the samples were determined, including thermic treatment, Blaine particle finesse, real density and apparent density, porosity, volume stability, and the initial and final setting times. Finally, a detailed study was conducted to establish the technical properties of the samples through chemical analysis of technological quality, chemical analysis of pozzolanicity, mechanical compressive strength tests at 7, 28, and 90 days, and a non-destructive ultrasonic pulse test. The results using SEM and XRF show that the samples are composed entirely of colonies of diatoms whose bodies are formed by silica between 83.8 and 89.99% and CaO between 5.2 and 5.8%. Likewise, this indicates a remarkable reactivity of the SiO2 present in both natural diatomite (~99.4%) and calcined diatomite (~99.2%), respectively. Sulfates and chlorides are absent, while the insoluble residue portion for natural diatomite is 1.54% and 1.92% for calcined diatomite, values comparatively lower than the standardized 3%. On the other hand, the results of the chemical analysis of pozzolanicity show that the samples studied behave efficiently as natural pozzolans, both in a natural and calcined state. The mechanical tests establish that the mechanical strength of the mixed Portland cement and natural diatomite specimens (52.5 MPa) with 10% PC substitution exceeds the reference specimen (51.9 MPa) after 28 days of curing. In the case of the specimens made with Portland cement and calcined diatomite (10%), the compressive strength values increase even more and exceed the reference specimen at both 28 days (54 MPa) and 90 days (64.5 MPa) of curing. The results obtained in this research conf

Climate change is already an undeniable reality, and it is a direct consequence of our society’s lifestyle and the indiscriminate use of certain materials, such as Portland cement, which causes the emission of gases and waste that contributes to the greenhouse effect. The object of this work is to present the results obtained from research on pyroxenic andesites that have become altered to zeolite and their use as alternative, eco-efficient materials that improve the quality of cement through a standardized partial substitution. In this work, four samples of pyroxenic andesites altered to zeolites (PAAZ) and two samples of unaltered andesites (UPA) were analyzed. The methods used in this study are as follows: petrography of thin section (PTS), chemical analysis of X-ray fluorescence (XRF) and phase determination by X-ray diffraction (XRD). Other tests were carried out to determine the quality of the PAAZ from a technical and practical application point of view, such as chemical analysis of pozzolanicity (CPT) at 8 and 15 days, as well as mechanical compression tests at 2, 7, 28 and 90 days. Petrographic and phase analyses show that the original mineral components of the samples such as pyroxene, amphibole, plagioclase and mica were leached and replaced by more than 90% with mordenite and smectite. XRF analyses indicates an anomalous rise in SiO2, a drastic reduction in alumina Al2O3 and a significant increase in alkaline compounds over alkaline-earth compounds in samples of altered pyroxenic andesites (PAAZ) with respect to samples of unaltered andesites (UPA). The pozzolanicity test establishes that the samples of unaltered andesites do not behave like pozzolans at 8 or 15 days; however, altered andesites experienced remarkable pozzolanic reactivity in the same periods. The mechanical compression tests carried out on specimens made with PAAZ and Portland cement showed a growing increase in mechanical resistance from 2 days (15.2 MPa) to 90 days (72.1 MPa). These re

El TFG (Trabajo Final de Grado) realizado se centra en la fabricación de ladrillos y cerámicas, con énfasis en los ladrillos Clinker, un tipo de pieza cerámica vista. El proyecto abarca desde el análisis del proceso de fabricación, el estudio de las pastas cerámicas, el cumplimiento de la normativa española, y el abordaje del problema energético hasta el establecimiento de los métodos de ensayo para evaluar sus propiedades. Además, se explicará la metodología utilizada en cada uno de los ensayos, así como los resultados y un breve análisis de los mismos, determinando de esta manera la validez de los ladrillos para poder ser comercializados fuera de la comunidad europea. ABSTRACT The FDP (Final Degree Project) carried out focuses on the manufacture of bricks and ceramics, with emphasis on Clinker bricks, a type of exposed ceramic piece. The project ranges go from analyzing the manufacturing process, studying ceramic pastes, examining Spanish regulations, addressing the energy problem to establishing test methods to assess their properties. The methodology of each test will be shown, as well as the results and a brief analysis of them. In this way, determining the validity of the bricks to be able to be commercialized out of the European community.

Este proyecto de fin de grado busca conectar la tecnología con la sostenibilidad al desarrollar un prototipo que monitorice el proceso de fraguado del hormigón mediante sensores de temperatura de bajo costo. La monitorización en tiempo real permitiría asegurar la calidad del hormigón y corregir cualquier problema de resistencia a la compresión de manera rápida y económica. Además, se espera que esta monitorización contribuya a reducir las emisiones, optimizar la logística y gestión de los recursos naturales, y fomentar la innovación en la gestión sostenible de las canteras. La transformación digital industrial se considera clave para una construcción más sostenible. Abstract This undergraduate final project aims to bridge technology and sustainability by developing a prototype that monitors the concrete curing process using low-cost temperature sensors. Real-time monitoring would ensure concrete quality and enable prompt and cost-effective correction of compression strength issues. Additionally, it is expected that this monitoring will contribute to emissions reduction, optimize logistics and resource management, and foster innovation in sustainable quarry management. Industrial digital transformation is considered crucial for achieving more sustainable construction practices.

En este trabajo se presentan los resultados de la sustitución parcial de cemento Portland (REF) por caolín de baja densidad (DIA), caolín de baja alúmina (CAO-BA) y caolín de alta alúmina (CAO-AA) para el ensayo en morteros en proporciones de 10, 25 y 40%. Para lograr dichos objetivos se prepararon las muestras y en una primera etapa, se realizaron análisis químicos y ensayos de puzolanicidad a 8 y 15 días con tal de poder ver si cumplen las propiedades puzolánicas. Por último, se realizaron ensayos de resistencia mecánica a compresión a las edades de 7, 28 y 90 días en probetas con las diferentes proporciones, tanto en forma natural, como activada. Los ensayos químicos fueron satisfactorios, mostrando valores óptimos de la sílice reactiva, algunas muestras, aunque no cumplieron los ensayos de puzolanicidad, tras su tratamiento térmico, lograron cumplirla y obtener unas propiedades puzolánicas. Los ensayos mostraron un aumento de las resistencias a compresión desde los 7 a los 90 días, la muestra DIA, tanto natural como activado, tiene un comportamiento que supera los valores del cemento de referencia para sustituciones del 10%, por otro lado, aunque las muestras de CAO-BA y CAO-AA no tengan propiedades puzolánicas, al activarse, logran cumplir los ensayos, y llegando a adquirir unas resistencias muy superiores a los de referencia, llegando a mejorarlas hasta en un 14,88%. Es por ello que las muestras de CAO-BA y CAO-AA podrán ser usadas para la fabricación de cementos con adición puzolánica tras un proceso de calcinación, logrando reducir costes energéticos en su producción, así como en la reducción de las emisiones de CO2, y aunque dichas muestras tengan mejores comportamientos a compresión, se deberá tener en cuenta la muestra de DIA-N, la cual, al no tener la necesidad de tener un proceso térmico, podría reducir aún más las emisiones de carbono y los costes energéticos, el cual se podrá hacer un estudio de viabilidad económico-financiera para saber qué muestra p

The geological nature of the territory of the Republic of Cuba has favoured the formation of large and varied deposits of volcanic tuffs enriched by various species of zeolites. Today, new zeolite deposits continue to be discovered in the country. This work aims to present the results of a study carried out in an unexplored area that is located approximately 1.2 km east of the Loma Blanca deposit, outside the mining operation limits. To carry out this research and to establish a qualitative comparison between both sample populations, four samples were taken from the study area, and another four were taken from the Loma Blanca deposit. The characterisation of the samples was performed by XRD, SEM, and XRF. The pozzolan quality was determined by the pozzolanicity test (PT) and quality chemical analysis (QCA). Finally, a study of the mechanical strength (MST) was performed at 7, 28, and 90 days, using mortar specimens made with PC/ZT: 75–25% and PC/ZT: 70–30%, respectively. The results of the studies using XRD, SEM, and XRF indicated that both groups of samples had a similar complex mineralogical composition, consisting mainly of mordenite and clinoptilolite accompanied by secondary phases such as quartz and amorphous materials in the form of altered glass. The pozzolanicity test showed that both the samples from the study area and those from the Loma Blanca deposit behaved like typical pozzolans, which is a trend that can be seen in the high values of mechanical strength to compression up to 72 MPa for the PC/ZT: 75–25% formulation and 66 MPa for the PC/ZT: 70–30%. The results obtained establish that the zeolite varieties detected in the study area are similar to those of the Loma Blanca deposit, which could have a positive impact on the increase in current reserves, especially for manufacturing pozzolanic cements with properties that contribute to the preservation of the environment.

Metropolitan construction and demolition waste (CDW) is currently an important source of recycled materials that, despite having completed their useful life cycle, can be reincorporated into the circular economy process (CEP); however, the recycling process is very selective, and waste material is not always fully satisfactory due to the intrinsic nature of the waste. This work aims to demonstrate and establish how to increase the effectiveness of the construction and demolition waste in more resistant mortars, by mixing it with zeolitised cinerite tuff (ZCT) at varying normalised proportions. To attain the objectives of this research, a series of tests were done: First, a chemical, physical and mineralogical characterisation of the CDW and the ZCT through XRF, XRD, SEM and granulometric methods. Second, a technological test was made to determine the mechanical strength at 7, 28 and 90 days of specimens made with Portland cement (PC) and mixtures of PC/CDW, PC/ZCT, and PC/CDW-ZCT. The results obtained through the characterisation methods showed that the sample of construction and demolition waste consisted of the main phase made of portlandite and tobermorite, and by a secondary phase consisting of quartz, ettringite and calcite; whereas the ZCT has a main phase of mordenite and a secondary phase of smectite (montmorillonite), amorphous materials consisting of devitrified volcanic glass, quartz and plagioclase. Mechanical strength tests established that specimens made with PC/CDW mixtures have very discreet compressive strength values up to 44 MPa at 90 days, whereas specimens made with PC/ZCT mixtures achieved a remarkably high mechanical strength consisting of 68.5 MPa. However, the most interesting conclusion in this research is the good result obtained in mechanical strength of the specimens made up of mixtures of PC/CDW-ZCT, which increased from 52.5 to 62 MPa at 90 days of curing; this fact establishes the positive influence of ZCT on waste in the mortar mixtu

University students face situations throughout their careers that are sometimes difficult to overcome due to their lack of experience or preparation. Mentoring programs in university education have been proven to be a great accompaniment tool to solve these difficulties in addition to helping students’ personal and professional development. Our study aimed to show the complete mentoring process that accompanies students in the most crucial stages of their university education at the School of Mines and Energy of Universidad Politécnica de Madrid. Three stages of interest were identified in which mentoring projects have been implemented through training activities at the Unit of Social Entrepreneurship, Ethics and Values in Engineering (UESEVI). At the beginning of their studies, two welcome actions are offered: Mentor and Monitor projects that provide administrative and academic support; during the development of their studies, the Mentoring with Energy project offers professional tutoring that helps students in their incorporation into the labor market and provides them with tools to select a specialty; and in the last stage, professional accompaniment is provided by the Gray Angels project that helps students to develop their future careers. The activities of UESEVI are a strategy in our School to guarantee the development of soft skills and compliance with quality education processes. The usefulness of these programs can be measured through the participation and interest of the students. A positive evolution of these projects has been observed over the years. They have been growing according to the demand and needs detected in the successive evaluations of the programs.

In recent decades, large amounts of construction and demolition waste (CDW) have been generated and accumulated throughout Europe, which is a challenge to manage and control nowadays. This work shows the results of a study carried out with samples of ceramic recycled aggregates (CRAs) and recycled concrete aggregates (RCAs) mixed with cement (C) in mortars. The main objective of this research is to demonstrate how, by adding CRAs and RCAs to a mixture of cement and natural aggregate (NA), it is possible to develop a high-strength mortar and achieve the best mixing ratio. To achieve these objectives, the characterization of the samples was initially carried out such as XRF, XRD and SEM. Next, tests were carried out on the products obtained, such as the consistency of the fresh mortar and the density of the specimens. Finally, a study of mechanical compressive strength was performed at 7, 28 and 200 days. The results show that although both CRAs and RCAs negatively affect the curing process of the specimens, it is possible to develop mortars with compressive strengths greater than 20 MPa. An obvious increase in mechanical compressive strengths was seen between 7 and 200 days of analysis. The results achieved in this research could be an important guide for the management of CDWs by local industries, thus favouring the development of the circular economy.

Este trabajo presenta los resultados de la sustitución parcial de cemento Portland (CREF) por fluorita natural (FN) y fluorita calcinada (FC) en morteros, al 10%, 25% y 40%. Para alcanzar estos objetivos, inicialmente se estudió una muestra de fluorita mediante difracción de rayos X, microscopía electrónica de barrido y espectroscopía Raman. En una segunda etapa se realizó un análisis químico y un ensayo de puzolanicidad a 8 y 15 días para establecer las propiedades puzolánicas de la muestra investigada. Finalmente, se realizó un ensayo de resistencia mecánica a compresión a 7, 28 y 90 días en probetas preparadas con mezclas CREF/FN y CREF/FC, en una proporción de 10%, 25% y 40%. Los resultados de difracción de rayos X, microscopía electrónica de barrido y espectroscopía Raman indicaron que la fluorita es la fase mineralógica principal. El ensayo de puzolanicidad y el análisis químico mostraron un aumento en la puzolanicidad de las muestras de 8 a 15 días. El ensayo de resistencia mecánica a compresión mostró un aumento en la resistencia a la compresión de 7 a 90 días para las muestras CREF/FN y CREF/FC. Los resultados obtenidos establecen que la fluorita produce efectos positivos en el mortero y contribuye a la ganancia de resistencia mecánica en el tiempo, siendo un material adecuado para la fabricación de cementos con adición puzolánica con reducción de emisiones de CO2, y reduciendo los costes energéticos de producción. Abstract This work presents the results of the partial substitution of Portland cement (CREF) by natural fluorite (FN) and calcined fluorite (FC) in mortars, at 10%, 25% and 40%. To meet these objectives, a sample of fluorite was initially studied by X-Ray Diffraction, Scanning Electron Microscopy and Raman Spectroscopy. A chemical quality analysis and a chemical pozzolanicity test at 8 and 15 days were carried out in a second stage to establish the pozzolanic properties of the investigated sample. Finally, a mechanical compressive strength test

This paper shows the results of a study focused on the evolution and properties of mortars made with a mixture of portland cement (PC) and natural mordenite (Mor). To begin, samples of mordenite, cement and sand were studied with X-ray diffraction (XRD), X-ray fluorescence (XRF) and granulometric analysis (GA). Next, mortars with a ratio of 75% PC and 25% mordenite were prepared to determine their initial and final setting times, consistency and density. Continuing, the density, weight and compressive strength of the specimens were determined at 2, 7, 28, 90 and 365 days. Finally, the specimens were studied using SEM, XRD and XRF. The results of the study of the mordenite sample showed a complex constitution where the major mineral component is mordenite, and to a lesser degree smectite (montmorillonite), halloysite, illite, mica, quartz, plagioclase and feldspar, in addition to altered volcanic glass. Tests with fresh cement/mordenite mortar (CMM) showed an initial setting time of 320 min and a final setting time of 420 min, much longer than the 212–310 min of portland cement mortar (PCM). It was established that the consistency of the cement/mordenite mortar (CMM) was greater than that of the PCM. The results of the density study showed that the CMM has a lower density than the PCM. On the other hand, the density of cement/mordenite specimens (CMS) was lower than that of portland cement specimens (PCS). The CMS compressive strength studies showed a significant increase from 18.2 MPa, at 2 days, to 72 MPa, at 365 days, with better strength than PCS at 28 and 365 days, respectively. XRD, XRF and SEM studies conducted on CMS showed a good development of primary and secondary tobermorite, the latter formed at the expense of portlandite; also, ettringite developed normally. This work proves that the partial replacement of PC by mordenite does not have a negative effect on the increase in the mechanical strength of CMS. It indicates that the presence of mordenite inhibi

This work presents the results of the partial substitution of Portland cement (PC) by natural fluorite (NF) and calcined fluorite (CF) in mortars, at 10%, 25% and 40%. To meet these objectives, a sample of fluorite was initially studied by XRD, SEM and Raman Spectroscopy (RS). A chemical quality analysis (CQA) and a chemical pozzolanicity test (CPT) at 8 and 15 days were carried out in a second stage to establish the pozzolanic properties of the investigated sample. Finally, a mechanical compressive strength test (MCST) at 7, 28 and 90 days was carried out on specimens made up with PC/NF and PC/CF mixes, at a ratio of 10%, 25% and 40%. XRD, SEM and RS results indicated fluorite as the major mineralogical phase. The CPT and CQA showed an increase in the pozzolanicity of the samples from 8 to 15 days. The MCST showed an increase in compressive strength from 7 to 90 days for both PC/NF and PC/CF specimens. The results obtained establish that fluorite produces positive effects in the mortar and contributes to the gain of mechanical strength over time, being a suitable material for the manufacture of cements with pozzolanic addition with a reduction of CO2 emissions, and by reducing the energy costs of production.

This work describes the newly discovered zeolites in the eastern region of Cuba. In the researched area, there have been no previous studies of natural zeolite exploration. Therefore, the results shown here are new. The main object of this research is to analyse five samples of zeolites and demonstrate their pozzolanic capacity and the possibility of their usage in the industrial manufacturing of pozzolanic cements. The study of the samples was performed by X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy (SEM). A chemical analysis (CAQ) to determine the quality of the samples as pozzolans was performed, by determining the total SiO2, reactive SiO2, total CaO, reactive CaO, Al2O3, MgO and the insoluble residue (I.R.). Lastly, an eight-day pozzolanicity analysis (PA) was carried out to determine the pozzolanic reactivity of the samples. The results obtained by XRD, XRF and SEM established that the researched zeolite samples have two main zeolitic phases: mordenite and clinoptilolite. Altered volcanic glass, quartz and smectite (montmorillonite) are the secondary phases. The results of the chemical quality analysis (CAQ) showed that the samples contain a considerable amount of reactive SiO2 and reactive CaO, as well as a low content of insoluble residue, which reinforces their properties as pozzolans. The results of the pozzolanicity analysis (PA) concluded that the analysed samples actively react with Ca(OH)2 after eight days. Based on all the results mentioned above, it is established that both mordenite and clinoptilolite behave like pozzolans and can be recommended for the manufacture of pozzolanic cements, which have more effective properties than Portland cement, in terms of physical, chemical and mechanical strength, low heat of hydration, resistance to sulphates, low CO2 emissions to the atmosphere and negligible impacts on the environment.

This work presents the results of the study of the physical, chemical, mineralogical and pozzolanic properties of the altered volcanic tuffs (AVT) that lie in the Los Frailes caldera, south of the Iberian Peninsula, and demonstrates their qualities as pozzolans for the manufacturing of mortars and pozzolanic cements of high mechanical strength. The main objective of this research is to show to what extent the AVTs can replace portland cement (PC) in mortars, with standardised proportions of 75:25% and 70:30% (PC-AVT). To achieve these objectives, three AVT samples were studied by a petrographic analysis of thin section (PATS), DRX, FRX and MEB. The pozzolanic properties were determined by three methods: electrical conductivity (ECT), chemical pozzolanicity tests (CPT) at 8 and 15 days and mechanical strength tests (MS) of the specimens at 2, 7, 28 and 90 days. Studies of a PATS, DRX, FRX and MEB showed that the AVT samples’ constitutions are complex where smectite (montmorillonite), mordenite, quartz, halloysite, illite, kaolinite, volcanic glass and lithic fragments coexist. The results of the ECT and CPT tests confirmed the pozzolanic properties of the samples analysed and proved an increase in mechanical strength from 2 to 90 days of testing.

This work aims to study the relationship between the compression resistance and velocity from ultrasonic pulses in samples of mortars with 25% of pozzolanic content. Pozzolanic cement is a low-priced sustainable material that can reduce costs and CO2 emissions that are produced in the manufacturing of cement from the calcination of calcium carbonate. Using ultrasonic pulse ve-locity (UPV) to estimate the compressive resistance of mortars with pozzolanic content reduces costs when evaluating the quality of structures built with this material since it is not required to perform an unconfined compression test. The objective of this study is to establish a correlation in order to estimate the compression resistance of this material from its ultrasonic pulse veloci-ty. For this purpose, we studied a total of 16 cement samples, including those with additions of pozzolanic content with different compositions and a sample without any additions. The results obtained show the mentioned correlation, which establishes a basis for research with a higher number of samples to ascertain if it holds true at greater curing ages.

El presente trabajo tiene la máxima de poner en valor el yacimiento de San José- Los Escullos, en Cabo de Gata (Almería). Para ello, se pretende estimar y determinar sus parámetros físicos mediante métodos geológicos-geofísicos. Las tareas llevadas a cabo para lograr el objetivo principal constan en primer lugar de la planificación, diseño y desarrollo de una campaña de tomografía eléctrica. El contexto geológico de la zona permite caracterizar litologías en base a la resistividad eléctrica de los materiales y su distribución en el subsuelo. Adicionalmente, el acceso a testigos permitió la realización de análisis mineralógicos a distintos niveles de profundidad. La conclusión más evidente de este trabajo proviene de integración de todos los datos obtenidos, productos de métodos directos e indirectos. Así, el resultado deriva en un modelo geológico 3D que ilustra el desarrollo en superficie y en profundidad del cuerpo mineral. ABSTRACT The aim of the current work is to value San José- Los Escullos ore deposit located in Cabo de Gata (Almería). It is known as the only productive zeolite deposit in Spain. The target is to estimate its physical properties by means of geological-geophysical methods. The primary task was to planned, designed and proceeded an electrical tomography campaign in order to define lithologies according to the resistivity’s distribution of the sub soil. Additionally, accessing to the testing drill allowed to take samples to make a new testing based on mineralogical criteria. The main conclusion has been drawn from analysing, integrating and modelling the data gathered from both, direct and indirect methods. The result is focused on a 3D geological model where the behaviour of the orebody is displayed.

This work deals with anomalous concentrations of natural mordenite in the southeast of Spain. The X-ray diraction (XRD) and scanning electron microscopy (SEM) studies evidenced that the samples contain mainly monomineral zeolitic phase of mordenite (70% to 74%), usually accompanied by smectite (montmorillonite), the principal component of bentonite. A study of the applicability of these zeolites is presented to establish the potential use as pozzolanic cements. For comparative purposes, synthetic commercial mordenite is also characterized and tested. The initial mixtures were prepared using cement and mordenite at a 75:25 ratio. Chemical analysis and a pozzolanicity test showed the high pozzolanic character. These mixtures were further added to sand and water, yielding the cement specimens to be used as concrete. Mechanical test results showed that the mechanical compression at 7 and 28 days fall into the range of 19.23 to 43.05 MegaPascals (MPa) for the cement specimens built with natural mordenites. The obtained results fall in the same range of cement specimens prepared with natural clinoptilolite, using mixtures within the European requirement for commercial concretes. Thus, these results and the low cost of natural mordenite of San José de los Escullos deposit supports the potential use of natural mordenite as pozzolanic cement.

Lejos de haber alcanzado una igualdad en términos de energía, vivimos en un mundo “en desequilibrio”, donde los llamados países del Norte están ya muy por delante de los países del Sur, en lo que a energía se refiere. Lograr reducir esa brecha energética no es una tarea fácil. Una cosa está clara, y es que esto es un desafío global del que todos deberíamos sentirnos partícipes, sentirnos involucrados. Sin embargo, parece que los países desarrollados tienen tendencia a destinar dinero, organizar voluntariados y otras acciones sociales en este marco, sin que realmente aporten un conocimiento que permita desarrollar la autonomía de los destinatarios. Podríamos preguntarnos hasta qué punto esa ayuda es útil. ¿Qué impacto buscamos tener como sociedad, como nación o como individuo? Por otro lado, el reto del acceso a la energía es uno de los objetivos marcados por la ONU en el marco de la Agenda 2030. El ODS7 (Objetivo de Desarrollo Sostenible 7) tiene como una de sus metas garantizar el acceso universal a servicios energéticos asequibles, fiables y modernos. Todo ello porque se considera que la falta de acceso adecuado a la energía supone realimentar el círculo vicioso de la pobreza. Intentar dar solución a este problema nos plantea inicialmente problemas técnicos. Hay muchas alternativas energéticas, y hemos de valorar las características y la adecuación de cada una de ellas, tanto para la ejecución de cada proyecto concreto como para la consecución de los Objetivos de Desarrollo Sostenible. Por otro lado, este problema global necesita de una respuesta multidisciplinar. Tenemos que tener en cuenta aspectos técnicos, pero también financieros o sociales. Desde el punto de vista de la financiación, este trabajo analiza el papel de la Responsabilidad Social Corporativa en la gestión de proyectos, qué factores hemos de tener en cuenta considerando que en una empresa hay objetivos muy diferentes: objetivos financieros y estratégicos, y aquellos otros que engloban un aspecto m

En este proyecto se presenta un modelo computacional, en un Sistema de Información Geográfica (SIG), para el mapeo de la distribución en 3D en la que los hidratos de gas del fondo marino serían estables. La construcción del modelo se compone de dos pasos principales:(i) la construcción de modelos digitales del terreno para las tres variables que controlan el campo de los hidratos en el medio marino (temperatura del fondo marino, gradiente geotérmico y batimetría/presión) a partir de los datos 3D disponibles en bases de datos públicas y de acceso libre y (ii) el cálculo de la potencia de la zona de estabilidad de los hidratos mediante las funciones de equilibrio de gas para los hidratos de gas biogénicos. La solución se basa en una función trascendental, que ese resuelve de forma iterativa en un entorno SIG. El modelo se ha aplicado en los márgenes continentales europeos y representa la distribución de la base de la zona de estabilidad de los hidratos de gas para composiciones de gas biogénicas = This project shows a computational model implemented in a Geographic Information System (GIS) environment, for the 3D mapping of the gas hydrate stability field in the subseafloor. The construction of the model consists of two main steps: (i) the development of digital terrain models for the three oceanographic variables that control the gas hydrate stability field (seafloor temperature, geothermal gradient and bathymetry/pressure) from 3D information avaible in public and free databases; and (ii) the calculation of the thickness of the hydrate stability zone using the gas balance functions for biogenic gas hydrates. The solution is based on a transcendental function, which is solved iteratively in a GIS environment. The model has been applied to the European continental margins and represents the base distribution of the gas hydrate stability zone for biogenic gas compositions.

The Technical University of Madrid, within the Spanish context, has profited from the introduction of a System of Internal Quality Assurance to build a road on the grounds of previous work on the culture of ethics in engineering. This way may drive the students training to incorporate in their curricula, leadership instruments that can be used for the recognition and acquisition of social responsibility. The road is paved with various educational elements, either mandatory, such as the “Mentoring Project” (peer support program), or optional, such as “Monitoring” (peer academic support program), “Ethics and Values in Engineering” (with social entrepreneurship projects) and “Service-Learning” (methodology that combines learning objectives with community service). This strategy, combined with the convergence of the European Higher Education Area, allows selecting those students who are able to integrate in their professional assets the idea and commitment of making the human development more sustainable,since the named experiences work towards the Sustainable Development Goals.

El trabajo realizado en estos documentos tiene la finalidad de caracterizar 12 muestras procedentes de los yacimientos de puzolanas naturales de la región de Holguín, Cuba. Dicha caracterización sigue un plan de ensayos en diferentes laboratorios e instituciones cuya finalidad es valorizar dichas puzolanas como materiales de aplicación en cementos y morteros para la construcción de viviendas de bajo coste con un fin social. Así mismo se realiza una valoración medioambiental mediante el estudio comparativo de la huella de carbono de distintos cementos. La metodología seguida se dividió en el plan de laboratorio en el que se marcaron los distintos ensayos a realizar para muestras recogidas de yacimientos seleccionados y muestras de escorias extraídas de una planta siderúrgica y el análisis medioambiental realizado mediante el software EcoInvent 3.0 del que recogieron los datos y con los cuales se hizo una valoración ambiental, mediante el software OpenLCA. Tras el análisis de los resultados obtenidos se concluye que las muestras estudiadas presentan propiedades y características óptimas para su uso en la fabricación de cementos, morteros y hormigón. El proceso de dichos materiales será próxima al yacimiento de esta forma se mejorarían los aspectos logísticos y económicos y se justificaría la fabricación de productos con un coste de producción moderado y con la suficiente calidad para su utilización en viviendas sociales. Como aspecto colateral se ha calculado la reducción del dióxido de carbono en la atmósfera al utilizar estos materiales puzolánicos. Abstract The work carried out in these documents has the purpose of characterizing some samples collected from the natural puzzolans deposits of the Holguín region, Cuba. This characterization follows a plan of tests in different laboratories and institutions whose purpose is to value said pozzolans as application materials in cements and mortars for the construction of low cost housing with a social purpose. Likewise, i

El presente trabajo tiene la finalidad de caracterizar los yacimientos de puzolanas naturales de la región nororiental Cuba, y determinar sus posibles aplicaciones en la fabricación de cementos y morteros para la construcción de viviendas sociales en dicha región. Las tareas contempladas en el desarrollo de este proyecto se dividen en dos partes fundamentales; la primera, que describe las campañas de campo in situ en las cuales se llevaron a cabo trabajos de reconocimiento geológico y muestreo, con la asimilación de muestras naturales procedentes de los yacimientos seleccionados, así como muestras de escorias extraídas de una planta siderúrgica. La segunda parte se refiere a la campaña de laboratorio, en cuyo marco se ha realizado una gran variedad de ensayos para determinar la idoneidad las muestras, entre los cuales se mencionan: el método de difracción de rayos X, la microscopía electrónica de barrido, el análisis químico de los componentes, el análisis químico de puzolanicidad, el ensayo granulométrico, la superficie específica, la densidad real, la resistencia a la heladicidad, las resistencias mecánicas y la determinación de la velocidad de propagación del ultrasonido a través de las probetas de morteros. Tras el análisis de los resultados obtenidos se concluye que las muestras estudiadas presentan las propiedades y características necesarias para la fabricación de cementos y morteros con características puzolánicas, justificándose, de este modo, la fabricación de productos con un coste de producción moderado y con la suficiente calidad para la construcción de viviendas sociales e infraestructuras, tan necesarias en la zona de estudio. Abstract The aim of the current work is to characterize the natural pozzolana of the in the northeastern region of Cuba and determine its possible applications in the manufacture of mortars and cement for the construction of social housings of this region. A great variety of tests have been run to obtain the characterization of