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The water ingress plays an important role in building materials’ degradation. The use of lightweight aggregates is interesting in terms of sustainability, because they reduce the density of cement-based materials, among other advantages. The development and use of new lightweight aggregates, such as cork granulates, is a current research topic. In the present work, water ingress performance of sustainable mortars which combined expanded and natural cork aggregates and cements with slag, fly ash and limestone has been studied. Mortars produced with sand and expanded clay were also prepared. Bulk density, water absorption, drying capacity and gel and capillary pores were studied. Tests were carried out at 28 days and 1 year. A good behavior has been generally observed when an addition was incorporated to the binder, especially slag or fly ash. Regarding the new non-standardized lightweight cork aggregates, mortars with natural cork showed lower water absorption and lower volume of permeable pore space in the long term than mortars with expanded cork. At one year, natural cork mortars had an adequate water absorption performance compared to those with expanded clay, which may be due to the high volume of small capillary pores (100 nm–1 µm) in natural cork mortars. This work was partly funded by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB/04029/2020, and under the Associate Laboratory Advanced Production and Intelligent Systems ARISE under reference LA/P/0112/2020. The work was also partially funded by FEDER through the COMPETE2020 program, Portugal 2020, within the scope of project CENTRO-01-0247-FEDER-047067 (LIFE4STONE). José Marcos Ortega is indebted to the Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital de la Generalitat Valenciana (Spain) for a fellowship of the BEST/2020 programme (reference BEST/2020/079).

One of the most important factors that define the effectiveness of Textile Reinforced Mortar (TRM) is their bond capacity to the substrate. This property may be compromised in case of exposure to high temperatures, although the information available on this topic is very limited at the moment. This paper analyzes the bond behavior on clay brick substrates of TRMs with carbon or glass textiles and different hydraulic lime mortar matrix. The effect of bond length and 3 levels of exposure temperature (20, 200 and 400 °C) are studied. The results show that at 200 °C the TRMs analyzed retain a significant part of their bond capacity, although textile slippage within the mortar matrix occurs and the tensile capacity of the fibers cannot be fully exploited, even if the meshes are properly anchored. At 400 °C the bond capacity may be completely lost, and debonding at the matrix-to-substrate interface may occur at very low stresses, depending on the properties of each TRM. This research has been funded by the Spanish Ministry of Science, Innovation and Universities, grant number RTI2018-101148-B-100.

Various countries have implemented the use of recycled concrete aggregates (RCA) as an alternative to reduce the use of natural resources. The replacement of RCA for natural aggregates (NA) in concretes is limited to small percentages because of the quality of the old mortar which is still adhered to the RCA. This mortar is more porous and absorbent, weakening the RCA and causing losses in the physical and mechanical properties of new concretes. In addition, the smaller the particles, the greater the amount of adhered mortar, which is why its use in concrete is limited and the fine fraction tends to be discarded. In this study, the use of RCA coated with recycled binder paste (RBP) (smaller than 45 μm) from the crushing of the RCA itself is sought to strengthen weak adhered mortar and improve the properties of the RCA through an economic and sustainable treatment by using the waste of the waste. Therefore, the mechanical, physical and chemical behavior and durability of the concretes are assessed by the use of RCA coated with RBP (replacing by 0%, 50% and 100%). The results indicate a reduction in the mechanical and physical properties of the concrete for the highest replacement percentage of RCA. Nevertheless, the coated recycled aggregate concrete (RAC) showed superior behavior to the untreated RAC, obtaining compressive strengths close to the control and a remarkable improvement in the physical assays. This work was supported by the Agencia Nacional de Investigación y Desarrollo de Chile (ANID) under Grant No. FONDECYT REGULAR 1211135.

The use of ternary binders in commercial cements is very low, at least in Spain. A possible field of application of these ternary cements would be the rehabilitation of coatings of old buildings, whose performance may be affected by the external environment. The goal of this research is to analyze the comparative effects of two in-situ environments in the microstructure and several service parameters of mortars with several ternary binders. The real environments verified the requirements of classes XC3 and XC4 of Eurocode 2. The mortars were also exposed to an optimum condition. Reference mortars with ordinary Portland cement and binary mortars were also studied. Mercury intrusion porosimetry, carbonation depth measurements and mechanical strength tests were performed. The real in-situ environments produced a carbonation development, an overall lower pore refinement and worsening of mechanical properties. Mortars which incorporated at least one active addition generally presented a better performance. This research has been financially supported by the Conselleria de Educación, Investigación, Cultura y Deporte (currently re-named as Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital) of Generalitat Valenciana (Spain) through the project code GV/2019/070 and by the Ministerio de Ciencia e Innovación of Spain through the project code RTC2019-006964-3. Authors express their gratitude to Cementos Portland Valderrivas S.A. for supplying the cement CEM I 42.5 R and the slag, fly ash and limestone additions used in this work. The results included in this paper were obtained in the PhD thesis carried out by Javier Ibáñez-Gosálvez at University of Alicante (Spain).

The behavior of masonry walls strengthened with Textile Reinforced Mortars (TRM) is a topic that has received considerable attention from researchers in recent years. However, the response of such elements after exposure to high temperature is an issue that remains to be explored extensively. This study analyzes the behavior of TRM-strengthened brick masonry panels with glass and carbon fiber meshes subjected to temperatures up to 600 °C, and subsequently tested under diagonal compression. The reinforcements were applied before or after temperature exposure, to analyze the effectiveness of damaged or undamaged TRMs, thus simulating different scenarios that might occur in a real building under a fire event. In general terms, the results showed that TRMs with carbon fibers exhibited a better response in these conditions, restoring the walls to their original capacity and providing additional ductility, whilst reinforcements with glass fibers seemed to be more affected by temperature. Finally, the experimental results are here compared to predictions from available design guides, in order to assess the accuracy that these codes would provide in these circumstances. This research has been funded by the Spanish Ministry of Science, Innovation and Universities, grant number RTI2018-101148-B-100.

Uno de los aspectos más importantes que determina la eficacia de los Textile Reinforced Mortars (TRM) es su capacidad de adherencia respecto del sustrato base, cuestión esencial para garantizar una correcta transmisión de tensiones. Aunque este tema ha sido objeto de diferentes investigaciones durante la última década, la adherencia bajo el efecto de temperaturas elevadas apenas ha sido analizada hasta la fecha. En este trabajo se plantea el estudio experimental de la adherencia entre muros de ladrillo cerámico y distintas soluciones de TRM, con mallas de fibras de carbono o vidrio y diferentes matrices. Los ensayos se realizan a temperatura ambiente y tras exposición a 200 y 400 ºC, a fin de evaluar la incidencia que un eventual incendio podría tener en un edificio reforzado con estos materiales. Los resultados muestran, en líneas generales, que la exposición a temperaturas elevadas reduce notablemente la adherencia y puede comprometer seriamente la eficacia de estos refuerzos. Puede concluirse, por tanto, que aunque los TRM se perciben con frecuencia como sistemas resistentes al fuego y que pueden emplearse sin protección, en realidad no es así. Esta investigación ha sido financiada por el Ministerio de Ciencia, Innovación y Universidades, a través del proyecto RTI2018-101148-B-100.

Historical buildings are located in the city center, near squares where celebrations take place. These festivities usually include pyrotechnic events that impose blast loadings on historical buildings. In this paper, a methodology for the analysis of the dynamic response of historical buildings is presented, and applied to the Altamira Palace — a historical building listed as Spanish National Monument located in Elche (Spain) — during the experimental campaigns that registered the effect of two different pyrotechnic events. Vibration levels associated with these events are presented and analysed according to several international standards and scientific recommendations, in order to avoid even cosmetic damages. The qualitative analysis of the accelerograms, registered during both events, served to identify the different parts of the spectacle, in which the highest accelerations were induced during the last phase (commonly known as the earthquake). Based on the quantitative analysis of the signals, the most significant frequency range in terms of possible damage to the monument was detected below 10 Hz. In this range, the measurements showed peak accelerations much higher than those limits recommended in the different standards and scientific reports.

Due to the present significant need to repair and maintain our buildings and the building repair sector’s minimal experience in special structural elements, we here describe a study on the repair of ceramic violin joist slabs in an actual intervention on a building erected in the 1950s that had been unsuccessfully repaired several times. Due to damp and being close to the sea, the main reinforcement elements had undergone considerable corrosion causing a significant risk to the building’s safety. The intervention necessarily involved replacing the affected steel rebars with appropriate elements with mechanical and corrosion resistance properties, as required by the latest building codes. An appropriate strengthening and repair system was developed with a stainless steel prosthesis fitted to the lower third of the joists that almost tripled their resistance, gave them 120 min of fire resistance, and increased their durability against corrosion at a cost of less than 50% of the current repair systems with minimum generation of construction waste. One of the most appealing characteristics of this new repair system is its avoidance of the full replacement of the joists, which can be considered as a relevant contribution to the sustainability of the construction industry.

There are many available studies on the reinforcement of columns by confinement with composite materials. However, in the particular case of stone elements, there is a lack of information regarding the performance of this solution under adverse conditions, which may occur during the life service of the structure. In this research, the confinement of calcarenite samples with a Fiber Reinforced Polymer (FRP) jacket has been studied in different scenarios, which simulate real conditions of structural retrofitting works. Specifically, the FRP’s efficiency was assessed in water saturation specimens, in damaged samples due to previous load, or the FRP jacket was casted directly in preloaded stone columns. As a general conclusion, FRP could improve notably the compressive strength of the unconfined material. In addition, the mechanical behavior seemed to depend on the FRP properties rather than the actual damage suffered by the rock core. This research was funded by Spanish Ministerio de Ciencia, Innovación y Universidades, grant number [RTI2018-101148-B-I00].

Although one of the main advantages of Textile Reinforced Mortars (TRM) is their non-combustible character, their behavior against fire or high temperatures has not been sufficiently studied at present. This work analyzes the behavior of different commercial systems containing inorganic mortars and fabric reinforcements based on glass, carbon and basalt fibers, subjected to different temperature levels. To characterize the mechanical response of the different systems, non-destructive tests have been carried out to determine the dynamic modulus of elasticity of the different materials, and subsequent destructive tests to determine their strength and stress-strain relationship. For this purpose, the TRM coupons have been subjected to uniaxial tensile tests and the deformations have been monitored using LVDT (Linear Variable Displacement Transducer) sensors and DIC (Digital Image Correlation), in order to evaluate cracking patterns and failure modes. The results show, in general terms, that the mechanical capacity of these materials is seriously compromised at temperatures in the order of 400 to 600 °C, which can easily be reached during a fire inside a building. Therefore, it can be concluded that although these systems are erroneously perceived as fire resistant in many cases, they may require additional protection depending on the specific use for which they are intended. The authors would like to acknowledge Mapei Spain S.A. for the materials supplied in this work. This research has been funded by the Spanish Ministry of Science, Innovation and Universities, grant number RTI2018-101148-B-100.

This study presents an alternative for the combined revalorization of two wastes with high volumes of generation, such as end-of-life tyres and glass. The experimental grid considered the analysis of the joint use of crumb rubber and glass powder in mortars. Crumb rubber is analysed as a sand replacement at 10% and 15% percentages, while glass powder is'. analysed as a 10% replacement for cement, considering the effect of two maximum size particles (38 μm and 45 μm). The results obtained show a decrease in the mechanical strength of the mortars, mainly associated with the use of crumb rubber, which increases with the increase in the percentage of crumb rubber used. However, a synergistic effect of the joint use of crumb rubber with glass powder was observed, which allowed the improvement of not only the thermal properties of the series but also those of water absorption, porosity and capillarity. This work was supported by the Agencia Nacional de Investigación y Desarrollo de Chile (ANID) (Grant No. FONDECYT REGULAR 1211135). Additionally, the authors gratefully acknowledge the partial support from Universidad de La Frontera (Chile) (Projects DI18-0023 and DI19-0019).

The development of non-destructive techniques has currently a high interest, such as those based on non-linear ultrasonic measurements. In this work it has been assessed the possible application of non-linear ultrasonic measurements for getting information related to the microstructure and properties of Portland cement mortars exposed to real and non-optimum environments. The pore structure was studied using mercury intrusion porosimetry and differential thermal analyses. Mechanical strengths and linear ultrasonic pulse velocity were determined. Regarding non-linear ultrasonic measurements, the results of parameters R and DIFA were analyzed. The tests were performed at 28 and 250 days. At later ages, a loss of microstructure refinement and a worsening of mechanical performance of the mortars were observed. The results of non-linear ultrasonic parameters R and DIFA overall agreed with those obtained for the microstructural and mechanical characterization performed. In particular, an adequate correlation between parameter DIFA and the pore size distributions was observed. This research has been financially supported by the Conselleria de Educación, Investigación, Cultura y Deporte (currently re-named as Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital) of Generalitat Valenciana (Spain) through the project code GV/2019/070 and by the Ministerio de Ciencia e Innovación of Spain through the project code RTC2019-006964-3. Part of the results presented in this manuscript was obtained in the PhD thesis carried out by Javier Ibáñez-Gosálvez at University of Alicante (Spain). Authors express their gratitude to Cementos Portland Valderrivas S.A. for supplying the Portland cement CEM I 42.5 R used in this work.

Industrial waste generated by the natural stone industry when working with limestone and dolostone is mainly composed of calcium carbonate and calcium magnesium carbonate. This mineral composition makes soil stabilization a potential use of the natural stone industry waste. However, much research must be carried out to fully understand the aptitude of this waste for soil improvement. In this work, the strength and microstructure of a clayey soil stabilized using limestone powder waste and lime or cement were studied employing the following techniques: unconfined compressive strength tests, mercury intrusion porosimetry, thermogravimetric analysis, X-ray diffraction, and scanning electron microscopy. Moreover, the effects of an aggressive environment were simulated using a sodium sulfate solution. Its effects were investigated from 7 days to 6 months. The results obtained show an increase in the unconfined compressive strength and a more compact structure for the samples with the industrial waste. Therefore, limestone powder waste from the natural stone industry can be used as a ternary element with lime and cement in soil stabilization. This work was supported by the Spanish Ministry of Universities under project number PRX21/00554 and the University of Alicante under project number GRE17-11 and developed within the framework of the project INNVA1/2021/8 of the Agencia Valenciana de Innovación.

[EN] The objective of this research is to study the effects produced by ternary binders which combine the addition of waste brick powder with fly ash, limestone, ground granulated blast furnace slag or waste glass powder in the microstructure and mechanical properties of mortars. In these ternary binders, the ordinary Portland cement was partially replaced by 10% of waste brick powder and 10% of another of the abovementioned additions. Mortars prepared with ordinary Portland cement without additions were also prepared. The microstructure was characterized with mercury intrusion porosimetry, electrical resistivity, and thermogravimetric analyses. Ultrasonic pulse velocity, compressive and flexural strengths were also determined. Mortars made using ternary binders with two active additions showed higher pore refinement and higher electrical resistivity at 250 days. Furthermore, their compressive strength and ultrasonic pulse velocity were relatively similar or even higher than that noted for reference specimens., Conselleria de Educacion, Investigacion, Cultura y Deporte (presently renamed as Conselleria de Innovacion, Universidades, Ciencia y SociedadDigital) de la Generalitat Valenciana, Spain, Grant/Award Number: GV/2019/070; Agencia Nacional de Investigacion y Desarrollo de Chile (ANID), Grant/Award Number: FONDECYT REGULAR 1211135

Masonry walls exhibit low tensile strength and high material heterogeneity, which makes them especially vulnerable against accidental loadings. There are a large number of studies, both experimentally and numerically, of the masonry behaviour under accidental loadings such as earthquakes. In this regard, the most relevant research focuses on (1) evaluating the shear strength of masonry with diagonal compression tests, (2) its behavior against in-plane cyclical loadings and (3) textile reinforced mortars TRM-based reinforcement techniques. However, there are very few studies that analyse the behavior of masonry under high temperature exposure, such as those that can occur in a fire. This paper describes the preliminary results of an experimental tests in which masonry panels (reinforced with TRM and unreinforced) have been tested in diagonal compression, previously damaged by the fire exposure. For this, masonry panels were subjected to different temperature levels, up to a maximum of 600 °C using an electric oven. In general, the results show that high temperatures causes a decrease in shear strength, as well as the transverse stiffness modulus. However, the walls reinforced with TRM based on carbon fiber were the ones that presented the best performance, since their mechanical properties were reduced by a smaller percentage. La investigación ha sido financiada por el Ministerio de Ciencia, Innovación y Universidades, a través del proyecto RTI2018-101148-B-100.

The use of lightweight aggregates in construction materials is a good solution for increasing the contribution to sustainability of civil engineering works, such as maritime ones. In this regard, the possibility of using cork granulates and expanded clay is a current research topic. The combination of eco-friendly cements with lightweight aggregates could provide solutions for developing new building materials. In this work, it has been studied mortars prepared with sustainable cements and the lightweight aggregates of natural cork and expanded clay. These cements incorporated slag, limestone and fly ash. Reference mortars with only sand as aggregate were also made. The total porosity and pore size distributions were obtained. The non-steady-state chloride migration coefficient and compressive and flexural strengths were also determined. The tests were performed at 28 days and 1 year. The differences in the total porosity between the natural cork and expanded clay series were not high, depending on the binder. Natural cork mortars showed similar or slightly higher migration coefficients than the reference and expanded clay mortars at 1 year. This adequate chloride resistance and the low mechanical strengths observed for the natural cork mortars recommend the possible use of this new aggregate in non-structural cement-based materials for civil engineering works exposed to maritime environments. This work was partly funded by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB/04029/2020, and by the FEDER through the COMPETE2020 program, Portugal 2020, within the scope of project CENTRO-01-0247-FEDER-047067 (LIFE4STONE). José Marcos Ortega is indebted to the Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital de la Generalitat Valenciana (Spain), for a fellowship of the BEST/2020 program (reference BEST/2020/079).

En este artículo se utiliza la Realidad Virtual Inmersiva (RVI) en enseñanzas técnicas tales como el Grado de Ingeniería Civil, el Grado en Fundamentos de la Arquitectura Técnica y el Máster de Ingeniería de Caminos, Canales y Puertos. Los objetivos de la investigación son: facilitar el entendimiento de los detalles constructivos, de la distribución volumétrica de espacios y del armado de elementos estructurales, algo que a veces es difícil de transmitir con las herramientas clásicas (Power Point, dibujos en pizarra, planos, etc.); aumentar la, a veces, escasa motivación del alumnado introduciendo nuevas tecnologías y facilitando su proceso enseñanza-aprendizaje; adaptar al alumnado a la rápida incorporación de la RVI en el ámbito laboral. La experiencia se llevó a cabo en cuatro asignaturas y se comprobó la mejora en la adquisición de conocimientos de los estudiantes dependiendo de la técnica utilizada: las tradicionales o la RVI. La evaluación de la consecución de los objetivos se realizó mediante cuestionarios de opinión y examinando objetivamente a los estudiantes sobre un caso en concreto analizado por una parte de ellos de la forma tradicional y por el resto mediante la RVI.

Este curso 2021-22 se ha organizado y celebrado un concurso denominado City Gamers. Ha sido creado por profesorado de los departamentos de Ingeniería Civil y de Edificación y Urbanismo y ha estado orientado a estudiantes de la ESO para fomentar en ellas y ellos el interés por el urbanismo, el funcionamiento y crecimiento sostenible de nuestras ciudades, y por las disciplinas STEM en general. Como vehículo del concurso se ha empleado, por un lado, el Objetivo de Desarrollo Sostenible 11 de la Agenda 2030 y, del otro lado, el videojuego Cities: Skylines®, el cual es un simulador de creación y gestión de ciudades. Las alumnas y alumnos participantes, por equipos paritarios de hasta seis, tuvieron que desarrollar dos actividades académicas basadas en los medios anteriormente citados, a lo largo de los meses de febrero, marzo, abril y mayo. Se recabó información para poder analizar el impacto formativo del concurso en el alumnado participante, tanto al inicio como al término del concurso, mediante sendos formularios distribuidos a las y los participantes. En esta memoria se describe con mayor detalle el concurso, las herramientas empleadas y un análisis del impacto formativo logrado con esta primera edición del concurso.

Las Tecnologías del Aprendizaje Cooperativo (TAC) constituyen sin duda una plataforma de gran interés para el profesorado y alumnado en el ámbito de la educación superior por las ventajas que ofrecen en términos de interacción y trabajo en equipo. En este estudio se recogen los resultados preliminares correspondientes a una experiencia educativa cuyo objetivo ha sido evaluar el impacto de implementar una metodología de aprendizaje cooperativo basado en la técnica del puzle de Aronson en la asignatura de últimos cursos Ultrasonidos y Aplicaciones del Grado en Ingeniería en Sonido e Imagen en Telecomunicación (GISIT) que se imparte en la Universidad de Alicante (UA). La experiencia docente ha demostrado que el uso de las TAC no solo incrementa el grado de implicación del alumnado en la resolución de una tarea común, sino que potencia sus habilidades de trabajo en equipo garantizando a su vez el rendimiento académico de las metodologías convencionales.

[EN] For improving the contribution of the cement industry to mitigate global warming, many strategies have been put into practice, such as the use of eco-friendly cements with the incorporation of additions substituting clinker. Nevertheless, the use of ternary binders for the production of commercial cements is still reduced, particularly in Spain. The purpose of this research is to characterize the long-term influence produced by the exposure to a real in situ inland Mediterranean climate condition in the pore network, parameters related to durability and mechanical performance of mortars made with ternary binders, which incorporated limestone, fly ash, and ground granulated blast-furnace slag, in comparison with mortars without additions and binary blended mortars. The site verified the specifications of exposure class XC4 of Eurocode 2. The ternary and binary binders accomplished the prescriptions of cement type CEM II/B. The pore network was studied with mercury intrusion porosimetry and electrical resistivity. Water absorption, diffusion coefficient, carbonation depth, ultrasonic pulse velocity, compressive and flexural strengths have been determined. The exposure to the environment produced after 250 days an increase in porosity, a loss of pore refinement, a rise of the carbonation depths, and a reduction in the mechanical strengths, highlighting the better overall performance of ternary mortar with both fly ash and slag, This work was supported by the Conselleria de Educación, Investigación, Cultura y Deporte (presently re-named as Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital) de la GeneralitatValenciana, Spain (grant code GV/2019/070)

[EN] The use of eco-friendly cements prepared with ternary binders could contribute to improving the sustainability of cement production. However, their use for manufacturing commercial cements is very low, at least in Spain. The purpose of this research is to study the behavior in the long term of mortars made with ternary binders which incorporated ground granulated blast furnace slag, fly ash, and limestone, exposed to environmental conditions compatible with the specifications of exposure class XC3 of the Eurocode 2, compared to mortars without additions and mortars with binary binders. The exposure station was placed in an underground floor of a building used as a garage with circulation of vehicles and moderately high CO2 concentration. The ternary and binary binders verified the prescriptions of cement type CEM II/B. The microstructure was characterized using mercury intrusion porosimetry and electrical resistivity. Water absorption, diffusion coefficient, carbonation depth, mechanical strengths, and ultrasonic pulse velocity were determined. A loss of microstructure refinement with time was noted for all the analyzed binders, probably related to the development of carbonation and drying shrinkage. The binary mortars with slag and fly ash and the ternary binder which combined them showed the best mechanical performance at 250 days., This work was supported by the Conselleria de Educacion, Investigacion, Cultura y Deporte (presently re-named as Conselleria de Innovacion, Universidades, Ciencia y Sociedad Digital) de la GeneralitatValenciana, Spain (grant code GV/2019/070).

In this study, CNTs and graphite have been incorporated to provide electrical conductivity and self-heating capacity by Joule effect to an epoxy matrix. Additionally, both types of fillers, with different morphology, surface area and aspect ratio, were simultaneously incorporated (hybrid CNTs and graphite addition) into the same epoxy matrix to evaluate the effect of the self-heating capacity of carbon materials-based resins on de-icing and ice-prevention capacity. The self-heating capacity by Joule effect and the thermal conductivity of the differently filled epoxy resin were evaluated for heating applications at room temperature and at low temperatures for de-icing and ice-prevention applications. The results show that the higher aspect ratio of the CNTs determined the higher electrical conductivity of the epoxy resin compared to that of the epoxy resin filled with graphite, but the 2D morphology of graphite produced the higher thermal conductivity of the filled epoxy resin. The presence of graphite enhanced the thermal stability of the filled epoxy resin, helping avoid its deformation produced by the softening of the epoxy resin (the higher the thermal conductivity, the higher the heat dissipation), but did not contribute to the self-heating by Joule effect. On the other hand, the feasibility of electrically conductive epoxy resins for de-icing and ice-prevention applications by Joule effect was demonstrated. This research was funded by the European Commission by the financial support of the MASTRO project, H2020 R&I programme. Contract no. 760940.

[EN] The service life of real construction elements is usually long, so the study of the behavior of cement-based materials with new pozzolanic additions in the very long term, after several hardening years, could be interesting. Here, the influence of using waste brick powder as 10% and 20% clinker substitution in microstructure and several durability-related parameters of mortars after 1500 hardening days (approximately 4 years) has been studied. According to the results obtained, the incorporation of brick powder overall improved the performance of mortars after 4 years, compared to reference mortars without addition, especially regarding the pore structure and chloride diffusion., This work was supported by the Conselleria de Educacion, Inves-tigacion, Cultura y Deporte (at present re-named as Conselleria de Innovacion, Universidades, Ciencia y Sociedad Digital) de la Generalitat Valenciana (Spain) [grant number GV/2019/070] ; and by the Agencia Nacional de Investigacion y Desarrollo de Chile (ANID) [grant number FONDECYT REGULAR 1211135]

Corrosion of the embedded steel is one of the main degradation problems limiting the service life of reinforced and pre-stressed concrete structures. A model able to provide approximate predictions of the evolution of the cracking process can be useful for designing accelerated corrosion tests of reinforced cement mortar or concrete specimens. An electrochemical model has been used for describing the inner displacements and strains caused by the accumulation of steel corrosion products around the rebar during electrically accelerated corrosion tests of reinforced cement mortar specimens with simple geometries. Subsequently, a mechanical model using the XFEM-Based Crack Growth Simulation module of Ansys Software, has been implemented to describe the distribution of stresses in the cross-section of the specimens. The combined electrochemical and mechanical model has led to acceptable predictions of the time to appearance of the first surface crack and the evolution of crack width over time. This combined model, which needs only data of a few experimental parameters, and uses only readily accessible standard software, could easily be implemented with other experimental configurations. For a more realistic description of the distribution of the tensile stresses and of the whole cracking process, the model must consider the initiation of several cracks, at least eight, around the rebar perimeter. The inclusion in the model of higher number of cracks increases greatly the computation time and effort, and may lead to convergence difficulties. This research was funded by the Spanish Agencia Estatal de Investigación (Grant code BIA2016-80982-R) and by the European Regional Development Fund (Grant code BIA2016-80982-R).

The influence of the type and concentration of the activator on the composition of the products formed and the microstructural development of alkali activated SiMn slag pastes and their evolution with curing time are studied. About 15–17 million tons of SiMn slag is produced per year, so valorising this residue is interesting for the economic and environmental scope. For this purpose, NaOH and WG with different concentrations of Na2O have been used as activators. The hydration products have been studied by X-ray diffraction analysis (XRD) and thermogravimetric analysis (TGA). Scanning electron microscopy (SEM) combined with energy dispersive spectroscopy (EDX) has been used to study the microstructure and elemental composition of hydrated phases. The advance of the degree of hydration with time and with the activator concentration is consistent with the mechanical behaviour of these pastes observed in previous studies. All the pastes show high microcracking due to the stresses caused by the shrinkage, as it has been observed in previous studies. Elemental composition data do not show significant differences regarding the type of activator with respect to the main elements and their relationship in the reaction products except for Mn. The main reaction product formed in the alkaline activation of SiMn slag is C-S-H with a low Ca/Si ratio, this being higher for pastes activated with NaOH compared to those with WG. In addition, the modification of the C-S-H structure is demonstrated by the presence of small amounts of Al and Mn and that Mg is not incorporated into it. The presence of hydrotalcite is not detected by XRD, but small amounts have been confirmed by TGA/DTG and SEM/EDX. The authors wish to thank 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”.

[EN] In order to improve the contribution to sustainability of cement production, several strategies have been developed, such as the incorporation of additions as clinker replacement. Regarding the production of commercial cements with additions, those made with binary binders are mostly produced. However, the use of ternary binders for manufacturing commercial cements is still very low, at least in Spain, and they could also be an adequate solution for producing eco-friendly cements. The objective of this research is to study the effects in the long term produced by ternary binders which combine the additions of blast furnace slag, fly ash and limestone in the microstructure, durability and mechanical performance of mortars, compared to mortars without additions and mortars made with binary binders. The ternary and binary binders accomplished the prescriptions for a cement type CEM II/B. The microstructure was characterized using mercury intrusion porosimetry, electrical resistivity and differential thermal analysis. Absorption after immersion, diffusion coefficient, mechanical strengths and ultrasonic pulse velocity were studied. The best performance was noted for ternary binder with both slag and fly ash, probably produced by the synergetic effects of slag hydration and fly ash pozzolanic reactions. These effects were more noticeable regarding the compressive strength., This work was supported by the Conselleria de Educacion, Investigacion, Cultura y Deporte (presently re-named as Conselleria de Innovacion, Universidades, Ciencia y Sociedad Digital) de la Generalitat Valenciana, Spain (grant code GV/2019/070).

Coatings and plasters are an integral part of masonry cladding, having a fundamental protective and aesthetic function. They are exposed to numerous aggressive actions, which produce their degradation over time. The utilization of lime, as a binder in masonry lining mortars, plays an important role in their durability and conservation. The objective of this work is to analyze the fresh and durability properties of lime-based mortars for their application in the restoration of old buildings. Four different kinds of mortars were studied with similar workability, using as binders lime putty, aerial lime, and hydraulic lime. The aggregates used consisted of sand and crushed rock powder. As fresh properties, the consistency (by using the flow table) and water retentivity were determined. With respect to durability-related properties, water absorption by capillarity and by immersion, drying kinetics, and carbonation depth were studied. Bulk density and porosity of the mortars were also obtained. Mortars with lime putty showed higher global porosity and water absorption by immersion, while aerial lime mortars presented lower porosity and higher water absorption by capillarity. Finally, the durability performance of all the studied lime mortars was overall adequate for being applied as masonry coatings in the restoration of old buildings. This work was partially funded through FCT-Foundation for Science and Technology, IP, within the scope of the R&D Unit Institute for sustainability and innovation in structural engineering-ISISE (UIDP/04029/2020), and by the ERDF through the COMPETE 2020 program, Portugal 2020, under the project POCI-01-0247-FEDER-033990 (iNBRail). The APC for publishing this article was funded by the Conselleria de Educación, Investigación, Cultura y Deporte (at present renamed as Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital) de la Generalitat Valenciana (Spain) (grant code GV/2019/070). The research stay of José Marcos Ortega at the University of Coimbra was financially supported in part by the University of Alicante.

[EN] One of the ways of lessening the CO2 emissions of cement industry consists of replacing clinkers with supplementary cementitious materials. The required service life of real construction elements is long, so it is useful to characterize the performance of these materials in the very long term. Here, the influence of incorporating waste glass powder as a supplementary cementitious material, regarding the microstructure and durability of mortars after 1500 hardening days (approximately 4 years), compared with reference mortars without additions, was studied. The percentages of clinker replacement by glass powder were 10% and 20%. The microstructure was studied using impedance spectroscopy and mercury intrusion porosimetry. Differential thermal and X-ray diffraction analyses were performed for assessing the pozzolanic activity of glass powder at the end of the time period studied. Water absorption after immersion, the steady-state diffusion coefficient, and length change were also determined. In view of the results obtained, the microstructure of mortars that incorporated waste glass powder was more refined compared with the reference specimens. The global solid fraction and pores volume were very similar for all of the studied series. The addition of waste glass powder reduced the chloride diffusion coefficient of the mortars, without worsening their behaviour regarding water absorption after immersion., This work was supported by the Conselleria de Educacion, Investigacion, Cultura y Deporte (presently re-named as Conselleria de Innovacion, Universidades, Ciencia y Sociedad Digital) de la Generalitat Valenciana, Spain (grant code GV/2019/070); by the Agencia Nacional de Investigacion y Desarrollo de Chile (ANID; grant number FONDECYT REGULAR 1211135); by FCT-Foundation for Science and Technology, IP, within the scope of the R&D Unit Institute for sustainability and innovation in structural engineering-ISISE (UIDP/04029/2020); and by the ERDF through the COMPETE 2020 program, Portugal 2020 (project POCI-01-0247-FEDER-033990 iNBRail).

This paper aims to study the viability of conductive cement paste and conductive concrete with the hybrid addition of carbon nanotubes (CNT) and graphite powder (GP) as a self-heating material for heating, ice formation prevention and de-icing in pavements. Different heating tests, ice-preventing tests and de-icing tests were performed with cement paste and concrete specimens. Results confirm that the conductive cement composites studied, with the addition of 1% CNT + 5% GP, exhibited heating, de-icing and ice-prevention properties, when applying constant AC/DC voltages between the two end sides of each specimen, with relatively low energy consumption. The main contribution of this work is to achieve a sufficient conductivity level for the development of the heating and de-icing function using this hybrid addition in concrete, which has not been used so far, in order to be applied in real concrete structures. The authors would like to acknowledge financial support received from European Union’s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 760940 and from the Generalitat Valenciana (Spain) (AICO/2019/050).

En este trabajo se ha realizado un análisis detallado de los resultados obtenidos en la asignatura Tecnología de Estructuras Geotécnicas del Máster en Ingeniería Geológica desde su implantación en el curso 2014-15 hasta el curso 2019-20. En base al anterior análisis se han detectado una serie de debilidades, por lo que se han planteado una serie de propuestas de mejora de la asignatura, que se articulan en implantar un sistema de evaluación consistente en la realización de actividades de evaluación continua. Estas propuestas se han puesto en práctica durante el presente curso 2020-21, dando lugar a una mejora en los resultados del proceso enseñanza-aprendizaje de la asignatura.

Although the confinement of compressed columns with composite materials has been extensively studied during the last decades, scarce research has been conducted in the particular case of reinforcement of stone or masonry elements subjected to high temperatures. This work reports an experimental study on the mechanical behavior of cylindrical stone specimens exposed to temperatures of 600 °C and subsequently cooled with two different methods: slow air cooling or rapid water immersion. The effect of confinement by means of carbon or glass fiber reinforced polymers (FRP) is studied. The mechanical properties of the rock are also analyzed by non-destructive tests, which constitute very appropriate techniques when working on heritage buildings. In general terms, it was found that the effect of temperature significantly reduced the strength and elastic modulus of the rock. On the other hand, FRP confinement provided large increases in strength and ultimate strain, compared to unreinforced samples. An important finding of this work is that the response of the confined specimens seems to depend basically on the properties of the FRP laminate, and not on the damage that the stone core may have suffered. Finally, the experimental results are compared with the predictions of analytical confinement models included in the most relevant international design guides. It has been proven that these models seem to provide accurate results in the case of unheated and unaltered stone, although they show larger deviations in the case of high temperature exposed specimens. The authors would like to thank Mapei Spain, S.A. for their support during this research, and supplying the materials for the specimen reinforcement. This research has been funded by the Spanish Ministry of Science, Innovation and Universities, grant number RTI2018-101148-B-100, and the University of Alicante, grant VIGROB-212.

Building Information Modeling (BIM) es una metodología de trabajo colaborativa que se ha venido adoptando de forma progresiva en la industria de la construcción mundial a lo largo del presente siglo. Los estudiantes de grado en Ingeniería Civil de la práctica totalidad de las universidades españolas actualmente terminan sus estudios sin conocer siquiera los aspectos fundamentales de esta metodología, crucial en su futuro laboral. Por ello, es necesario incorporarla de manera urgente a los planes de estudios de ingeniería civil, suponiendo una oportunidad excepcional para modernizar los contenidos de las asignaturas de la titulación a este tipo de metodologías de aprendizaje colaborativo basado en proyectos y herramientas TIC. Para ello, se realizaron encuestas a estudiantes y profesores de la titulación. Los resultados muestran que ambos colectivos poseen en general muy poca información y formación acerca de BIM; sin embargo, existe un amplio consenso en la necesidad de su implantación inmediata. Todo ello condujo al diseño de una estrategia a lo largo de los cuatro cursos que integran el título de grado, seleccionando aquellas asignaturas que pueden suponer un mayor impacto en su uso, y aprovechando además la oportunidad de emplear BIM como herramienta de vertebración metodológica de la titulación.

El presente trabajo se desarrolla en los estudios de Fundamentos de Arquitectura de la Escuela Politécnica Superior de la Universidad de Alicante. Abarca las asignaturas del ámbito de construcción de los tres primeros cursos de la carrera. Desde que se implementaron las nuevas titulaciones, hemos comprobado que el alumnado no percibe del todo el vínculo entre dichas asignaturas y esto perjudica el aprendizaje, y les dificulta incorporar los conocimientos adecuadamente. Nos plateamos que parte de la razón pueda radicar en la diferencia de las actividades planteadas en cada asignatura y en el diseño de los ejercicios que proponemos. Por eso para este trabajo recabamos la opinión del alumnado al respecto y, en consecuencia, proponemos y ensayamos un ajuste de los actuales trabajos prácticos de la asignatura para plantear un símil de un proyecto de edificación que comienza de forma muy elemental en primero y de va desarrollando, adaptándose después a los contenidos de la asignatura de segundo, retomando los detalles constructivos y rediseñándolos y, posteriormente, en tercero, se mantendrán los criterios de diseño de los dibujos y de las láminas, aumentando la complejidad del contenido y adaptando, en cada curso, los textos descriptivos a los contenidos de las asignaturas.

In this work, the feasibility of a combined treatment of electrochemical chloride extraction (ECE) and cathodic protection (CP) in reinforced concrete structures using a conductive cement-graphite paste as anode has been studied. It has been proven that the prior application of an electrochemical chloride extraction treatment leads to greater durability of the anode. It has been shown that for reinforced concrete structures located in aggressive marine environments, the combination of electrochemical treatments, first ECE to reduce the chloride content and then CP to maintain passivation conditions, is capable of providing adequate protection conditions for the reinforcement, provided that the appropriate current density value is applied, according to the average content of chlorides present in the reinforced concrete structures. En este trabajo se ha estudiado la viabilidad de un tratamiento combinado de extracción electroquímica de cloruros (EEC) y protección catódica (PC) en estructuras de hormigón armado utilizando como ánodo una pasta conductora de cemento-grafito. Se ha comprobado que la aplicación previa de un tratamiento de extracción electroquímica de cloruros conlleva una mayor durabilidad del ánodo. Se ha demostrado que, para estructuras de hormigón armado situadas en ambientes marinos agresivos, la combinación de tratamientos electroquímicos, primero EEC para reducir el contenido de cloruros y a continuación PC para mantener las condiciones de pasivación, es capaz de proveer condiciones adecuadas de protección a la armadura, siempre que se aplique el valor de densidad de corriente adecuado, de acuerdo con el contenido medio de cloruros presente en las estructuras de hormigón armado. Neste trabalho foi estudada a viabilidade de um tratamento combinado de extração eletroquímica de cloreto (EEC) e proteção catódica (PC) em estruturas de concreto armado usando uma pasta condutora de cimento-grafite como ânodo. Verificou-se que a aplicação prévia de um tratamento de extração eletroquímica de cloretos, acarreta uma maior durabilidade do ânodo. Foi demonstrado que, para estruturas de concreto armado localizadas em ambientes marinhos agressivos, a combinação de tratamentos eletroquímicos, primeiro EEC para reduzir o teor de cloreto e depois PC para manter as condições de passivação, é capaz de fornecer condições de proteção adequadas aos armadura, desde que seja aplicado o valor de densidade de corrente adequado, de acordo com o teor médio de cloretos presente nas estruturas de betão armado. This research was funded by the Spanish Agencia Estatal de Investigación (AEI), and Fondo Europeo de Desarrollo Regional (FEDER) through project BIA2016-80982-R. We acknowledge also funding from the Spanish Ministerio de Ciencia e Innovación (MAT2009-10866), and Generalitat Valenciana (PROMETEO/2013/035).

Cement composites with hybrid conductive fillers carbon nanotubes (CNT) and graphite products (GP), have been tested as strain sensors under varying temperatures (0 °C–60 °C), and moisture conditions (0%–100% saturation degree (SD)). Cement pastes with 1% CNT and 5% GP (purified expanded graphite) presented resistivity values between 50 and 75 Ohm·cm, and their strain sensing response was observed to be independent of the loading conditions. However, the gage factor increased up to four times for higher temperatures, and was influenced by the temperature time history. Gage factors were also increased when drying the material up to a SD of 71% or with entirely dried samples. This project has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement ID 760940, and from the Generalitat Valenciana grant AICO/2019/050.

La situación de pandemia generada por el COVID-19 ha establecido un nuevo escenario para el desarrollo de las actividades formativas dentro del ámbito académico universitario. En este contexto, los profesionales de la educación afrontan múltiples desafíos relativos a las modalidades educativas y metodologías de trabajo a adoptar en cumplimiento con las recomendaciones de las autoridades sanitarias. El presente trabajo recoge los resultados de una acción educativa orientada a complementar la docencia de la asignatura Ultrasonidos y Aplicaciones que se imparte en el Grado en Ingeniería en Sonido e Imagen en Telecomunicación (GISIT) de la Universidad de Alicante (UA). Dicha acción consistió en el diseño e implementación de una plataforma software modular que permitiese analizar diversos fenómenos y dispositivos ultrasónicos desde un entorno software familiar para estudiantes de dicho grado como es MATLAB. Con el propósito de evaluar la utilidad y prestaciones de dicha herramienta se preparó un ejercicio práctico a resolver por el alumnado seguido de una encuesta de satisfacción que también le permitiese aportar sugerencias de mejora. En general, los resultados de la experiencia indican que la herramienta desarrollada no solo ha favorecido la consolidación de conocimientos de la asignatura, sino que también ha permitido lidiar con algunas de las limitaciones asociadas a la situación de pandemia por COVID-19.

Masonry walls exhibit low tensile strength and high material heterogeneity, which makes them especially vulnerable against cyclic loading conditions, such as those typical in earthquakes. This paper presents the experimental results obtained from tests on three masonry walls reinforced with textile reinforced mortar (TRM) materials subjected to in-plane cyclic loading. These full-scale masonry walls were tested in the LARGE laboratory at the University of Alicante (Alicante, Spain). The walls had been built using a traditional construction technique, with solid clay bricks layered with lime mortar. One specimen was tested and damaged by in-plane cyclic loading and was subsequently strengthened by a vertical layer of TRM with an overlapping of 200 mm. It was then tested again until failure in a second test. In addition, another undamaged specimen had been previously reinforced with the same TRM technique and tested until failure, thus providing a third test. A network of sensors and digital image correlation systems were used to monitor displacements and crack patterns. The comparison between these experimental results made it possible to assess the effectiveness of TRM in restoring the structural integrity of damaged masonry walls and almost doubling their load-bearing capacity under cyclic loads. Conclusions obtained here provide valuable information to the scientific community, architects and structural engineers about the strengthening and repair of severely damaged masonry walls. The authors would like to thank the Mapei Company for its technical and financial support in the use of reinforcement materials (TRM). In the same way, we want to thank the support of the Grupo Puma Company for the materials used in the unreinforced specimens. This research has been funded by the Spanish Ministry of Science, Innovation and Universities, grant number RTI2018-101148-B-100. Authors would also acknowledge the support of the University of Alicante by the grant number UAUSTI20-10.

El aprendizaje para el desarrollo de los distintos sistemas constructivos y de las estructuras es un proceso que conecta el diseño, el cálculo y la solución de la materialización de una idea en cualquier proceso de definición arquitectónica. Existe una dependencia docente entre las asignaturas que imparten el conocimiento de la construcción en Introducción a la Tecnología de primer curso, Sistemas Constructivos Básicos y Avanzados de segundo curso, Sistemas Constructivos Singulares de cuarto y las asignaturas de Diseño Avanzado de Estructuras I, II, e Intervención y Mantenimiento en la Edificación que se imparten en el curso de Máster en Arquitectura. La formación del arquitecto requiere de todos los conocimientos constructivos que hagan posible el desarrollo del proyecto arquitectónico, por lo que es necesario la conexión de Proyecto y Tecnología en el itinerario docente del alumno: Conectar la idea proyectual y su construcción a partir de la materialización; Aplicar los condicionantes físicos externos: agua, viento, fuego, calor, ruido, etc. en la definición del elemento construido; Conocer los movimientos de los sistemas constructivos (térmicos, mecánicos, reológicos, etc.); Diseñar la solución arquitectónica a través del detalle constructivo del punto singular. Se realizan y ejercicios sencillos que contienen la aplicación estos conceptos para mejorar los resultados del aprendizaje de los estudiantes.

A problemática da durabilidade de estruturas de concreto armado inseridas em ambientes de severa agressividade se apresenta como uma das principais dificuldades enfrentadas pela cadeia da construção civil. Dos vários agentes capazes de degradar estas estruturas tem-se atenção especial aos íons cloreto capazes de causar a corrosão de armaduras, estes íons estão amplamente presentes em ambientes marinhos. Neste espectro, a estimativa de vida útil das estruturas de concreto armado se torna uma temática fundamental na avaliação da durabilidade de estruturas. Apesar de vários processos causarem penetração de cloretos no concreto tem-se praticamente como consenso que o mecanismo de difusão é o predominante, tendo-se como um modelo clássico de caracterização da penetração de cloretos a 2ª Lei da difusão de Fick. O processo de difusão iónica sofre forte influência do grau de saturação (GS) dos poros do concreto, está influencia incide diretamente sobre o coeficiente de difusão de cloretos (D). Ainda que se tenham desenvolvido metodologias de medição do GS elas se apresentam dispendiosas em tempo e recursos. Objetiva-se então apresentar estimativas do Grau de Saturação, baseadas nas condições ambientais de exposição da estrutura, e analisar a influência deste parâmetro na estimativa de vida útil de elementos estruturais de concreto armado sob a ótica da confiabilidade. São utilizados dados meteorológicos e de medição do GS de duas regiões litorâneas, sendo uma em Rio Grande, no sul do Brasil e outra em Santa Pola, sudeste da Espanha. Obtiveram-se modelos de estimativa do GS do concreto para cada situação pesquisada e também para ambos os ambientes em conjunto. Constatou-se então, através de uma abordagem probabilística, a forte influência do uso destes modelos na estimativa de vida útil de elementos de concreto armado. The problematic of the durability of reinforced concrete structures inserted in environments of severe aggressiveness is presented as one of the main difficulties faced by the civil construction chain. Of the various agents capable of degrading these structures, special attention is paid to chloride ions capable of causing corrosion of reinforcing steel, these ions are widely present in marine environments. In this sense, the estimated useful service life of reinforced concrete structures becomes a fundamental theme in the evaluation of the durability of concrete structures. Although several processes cause penetration of chlorides in the concrete, it is practically agreed that the diffusion mechanism is the predominant one, being Fick’s 2nd Law of diffusion a classic model for the characterization of chloride penetration into concrete. The ionic diffusion process is strongly influenced by the saturation degree (GS) of the pores in the concrete, it influences directly on the chloride diffusion coefficient (D). Although GS measurement methodologies have been developed, they are costly in time and resources. The objective of this study is to present estimates of GS, based on the environ-mental exposure conditions of the structure, and to analyze the influence of this parameter on the estimated useful service life of structural elements of reinforced concrete from the point of view of reliability. Meteoro-logical and GS measurement data from two coastal regions are used, one in Rio Grande, in southern Brazil and the other in Santa Pola, southeast of Spain. Concrete GS estimation models were obtained for each stud-ied situation and also for both environments together. It was verified, through a probabilistic approach, the strong influence of the use of these models in the estimation of useful service life of reinforced concrete structures. O presente trabalho foi realizado com apoio da Coordenação de Aperfeiçoamento de Pessoal de Nível Supe-rior - Brasil (CAPES) - Código de Financiamento 001.

El Trastorno por Déficit de Atención con Hiperactividad o TDAH es el trastorno neuropsicológico más frecuente en la infancia y adolescencia que afecta a los procesos psicológicos básicos implicados en el aprendizaje, la adaptación social y la adaptación afectiva. Los estudios realizados al respecto demuestran las características más significativas dentro del ámbito educativo: la inatención, el exceso de actividad y la falta de control inhibitorio. Algunos de ellos llegan incluso a estudiar grados universitarios [1]. Afecta al 3-7% de los niños, siendo más frecuente entre los varones. El diagnóstico suele realizarse en torno a los 5-8 años, coincidiendo con el inicio de la edad escolar. Según sus manifestaciones, donde se encuentran tres categorías diagnósticas: TDAH presentación predominante hiperactiva/impulsiva, TDAH presentación predominante con falta de atención y presentación combinada (cuando cumple los criterios para ambos tipos). El diagnóstico del TDAH es el inicio del proceso donde el sujeto, empieza a ser entendido dentro de su ámbito familiar y educativo [2]. Para ello, existen herramientas que desarrollan escalas, aunque dependen mucho del facultativo que los evalúa, por tanto, son subjetivos. El mayor inconveniente de estos sistemas de evaluación es que no suponen una observación objetiva en un contexto ecológico. Debido a ello existen diferentes investigaciones centradas en registrar medidas objetivas de movimiento en los sujetos, ya que la hiperkinesia es uno de los síntomas más característicos de este trastorno. Esta investigación ha sido desarrollada durante años y culminada con la creación de una herramienta que, en un contexto natural para el alumno, puede recoger información sobre su conducta motórica. La herramienta desarrollada se presenta como válida al comparar los resultados obtenidos con la misma y los resultados obtenidos mediante las herramientas utilizadas en al ámbito profesional. El trabajo se apoya en la red AccesUA, formada por un equipo interdisciplinar de docentes que tiene por objetivo facilitar la inclusión de alumnos con TDAH en el sistema educativo [3]. El trabajo propuesto pretende avanzar en la inclusión de los estudiantes con este tipo de afecciones de una forma teórico-práctica donde los alumnos de la asignatura Realidad Virtual del Grado en Fundamentos de Multimedia, sean los que evalúen sus experiencias personales y de entorno en cuanto a las dificultades de inclusión en alumnos con TDAH. El trabajo tiene por objetivo analizar el conocimiento de este trastorno por alumnos y profesores para poder proponer mecanismos de mejora en las prácticas docentes y la ayuda entre compañeros. El estudio presentado se basa en una metodología de trabajo colaborativo entre docentes de diferentes áreas para realizar un trabajo multidisciplinar [4], [5]. Para evaluar la experiencia educativa se emplearán cuestionarios en formato digital que serán contestados tanto por alumnos como por profesores de la Universidad de Alicante. Estos cuestionarios tienen intención de conocer el estado de conocimiento del TDAH de los integrantes del sistema universitario. Se desea destacar el soporte de la Red de Investigación “Red AccesUA: Trabajo colaborativo entre docentes y estudiantes para la inclusión de alumnos con dificultades relacionadas con el TDAH en el ámbito educativo.”, Red ICE 2020-2021 con código 5365.

El objetivo de esta innovación docente es dar a conocer las posibilidades de las herramientas de diseño geométrico avanzado para la definición de elementos de ingeniería civil en 3D, su relación e implementación con metodologías BIM y realidad aumentada (AR), y la realización de modelos reales a escala reducida mediante impresión 3D. Estas nuevas tecnologías aportan una motivación extra al alumnado, facilitan la asimilación y comprensión de los conceptos previamente desarrollados en clase, mejoran entendimiento de las relaciones y las colisiones entre cada parte del proyecto y el aportan una nueva forma de mostrar los resultados a los clientes, así como la adquisición de las competencias del plan de estudios. Para ello se realizará una experiencia docente utilizando estas nuevas tecnologías en el Máster de Ingeniería de Caminos, Canales y Puertos. Los medios tecnológicos necesarios para que los alumnos puedan disfrutar de esta nueva metodología son: una plataforma donde alojar proyectos BIM, una aplicación para dispositivos móviles de realidad aumentada y una impresora 3D con su software asociado. La propuesta docente será evaluada mediante dos rúbricas a los alumnos y alumnas, una antes y otra después de realizar la actividad.

The use of lime as a binder in masonry lining mortars plays an important role in its conservation and durability. Knowledge of the mechanical characteristics of pre-existing and restoration mortars is essential in order to guarantee the compatibility between them and for avoiding the appearance of pathologies. The paper mainly focuses on the study of the mechanical performance of lime-based mortars to be applied in rehabilitation works in old buildings. Four types of mortars were tested with very similar workability, based on lime putty, aerial lime, and hydraulic lime. Sand and crushed rock powder were used as aggregates. Compressive and flexural strengths of the mortars were determined, as well as their ultrasonic pulse velocity. Furthermore, specific tests were carried out to characterize the performance of the mortar when used as a binder for plasters and coatings, such as the development of cracking, superficial water absorption under low pressure, and pull-off strength. According to the results obtained, mortars with lime putty showed better mechanical properties, while those with aerial lime had better behavior regarding water absorption under pressure. Despite that, it was generally possible to verify the adequacy of the studied mortars to be used in the rehabilitation of masonry elements. This work was partially funded through the FCT—Foundation for Science and Technology, IP, within the scope of the R&D Unit Institute for sustainability and innovation in structural engineering—ISISE (UIDP / 04029/2020), and by the ERDF through the COMPETE 2020 program, Portugal 2020, under the project POCI-01-0247-FEDER-033990 (iNBRail). The APC for publishing this article was funded by the Conselleria de Educación, Investigación, Cultura y Deporte (at present re-named as Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital) de la GeneralitatValenciana (Spain) (grant code GV/2019/070). The research stay of José Marcos Ortega at the University of Coimbra was financially supported in part by the University of Alicante.

Among the largest producers of waste, the paper industry stands out due to its impact on human health and ecological balance. However, these residues may also contribute to a more environmental friendly brick industry, since the incorporation of fluxing agents may improve the firing process and the induced porosity reduces thermal conductivity of fired bricks. Therefore, this study aims to assess the feasibility of replacing clay with solid paper residue (PPR) from 2.5 to 17.5% in order to reduce resources depletion and improve brick performance. The original clay was characterized as a non-calcareous red clay with high contents of kaolinite. Several samples were made by extrusion and fired at 900 °C in accordance with industrial procedures. The addition of PPR led to increase shrinkage from 5 to 10% due to the effect of fluxing oxides which reduced pores volume and enlarged pores size. In addition, the impervious fraction was slightly reduced while the apparent porosity certainly increased (i.e. approx. 17%) due to the macroscopic pores developed by PPR combustion. This porosity produces lighter bricks (i.e. density decays from 1.76 to 1.39 g dm−3) with lower thermal conductivity (i.e. from 5.53 to 0.41 W m−1 K−1) but also reduces compressive strength (i.e. from 11 to 3 MPa) and increases water absorption (i.e. up to 24%). Nevertheless, toxicity is below the regulatory limits in all cases and fired bricks are easily adaptable to industrial procedures. It must be noticed that this work was supported by the Chilean National Commission on Research and Development (CONICYT) [grant number FONDECYT REGULAR 1180414]. Technical and human support provided by CICT of Universidad de Jaén (UJA, MINECO, Junta de Andalucía, FEDER) and by Centro de Manejo de Residuos y Energía (BIOREN) Universidad de la Frontera (Chile) are gratefully acknowledged.

One of the most aggressive attacks to which cement-based materials can be exposed is that produced by sulphate. During this attack, expansive products are formed, causing volumetric strains in hardened materials, which brings microcracking and the reduction of their strength and durability. The use of non-destructive techniques for characterizing the microstructure of cement-based materials, and for following the development of deleterious processes which can affect them, has become an important research field. Among them, non-linear ultrasonic (NLU) techniques have shown to be useful for evaluating the material degradation. The aim of this work is to study the possibility of using the NLU technique for the non-destructive evaluation of initial development of internal sulphate attack in cement-based materials. Cement pastes were prepared using ordinary Portland cement, to which an appropriate amount of calcium sulphate 2-hydrate was added during the setting for producing an internal attack in the samples. Furthermore, its effects in the microstructure have been followed with mercury intrusion porosimetry. The expansion and linear ultrasonic pulse velocity were also determined. The preliminary results indicate that the NLU technique could be useful for studying the development of sulphate attacks in the short-term, complementing the information provided by other techniques. This research was funded by the Conselleria de Educación, Investigación, Cultura y Deporte (at present re-named as Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital) de la Generalitat Valenciana (Spain) (grant code GV/2019/070), by the Spanish Agencia Estatal de Investigación (grant code BIA2016-80982-R) and by the European Regional Development Fund (grant code BIA2016-80982-R). M. M. is indebted to Spanish Ministerio de Educación, Cultura y Deporte for a pre-doctoral fellowship (FPU16/04078).

The aim of this work was to provide further confirmation of the possible use of non-linear ultrasonic techniques for detecting the cracking due to corrosion of steel reinforcements in concrete. To this end accelerated steel corrosion tests have been conducted on model reinforced cement mortar specimens, while monitoring the appearance and width evolution of visible surface cracks, and performing non-linear ultrasonic measurements based on the phenomena of harmonic distortion and intermodulation. A new parameter, based on the difference between the amplitude of the fundamental frequency and the sum of the amplitudes of all the first-order and second-order intermodulation products, has been proposed in this work. The results confirm that the appearance of visible surface micro-cracks are preceded and accompanied by the observation of strong non-linear features in the received signal. Furthermore, the new parameter proposed in this work is as efficient as the relative non-linearity parameters, classically used in harmonic distortion non-linear ultrasonic studies, for detecting the non-linear features associated with the critical events of the cracking of cement mortar due to embedded steel corrosion. A hypothesis has been developed considering the possible effect of the filling of the void space by liquid containing rust products after the formation of new cracks or the enlargement of its width. This filling process, which might be particularly enhanced by net convective transport of liquid, would explain the evolution of the values of all the parameters used for putting in evidence the non-linear elastic features after the critical events of the cracking process. This research was funded by the Spanish Agencia Estatal de Investigación (Grant code BIA2016-80982-R) and by the European Regional Development Fund (Grant code BIA2016-80982-R).

The bond mechanism between steel and concrete can be compromised during a fire and is one of the least investigated phenomena in concrete research. In this work we present a thorough review of the experimental data available on this topic. The results from the tests reported by a number of researchers have been systematically collected in a database. This work also reports the results obtained in the bond strength tests carried out on four batches of normal and high strength concretes exposed to temperatures up to 825 °C. The database provides the source for a multiple regression analysis which is performed in order to define a model aimed at predicting the bond strength as a function of several variables: the exposure temperature, the concrete compressive strength at ambient temperature, the type of fibre addition, the fibre volume fraction, the age at testing, the bond length and the concrete cover of the steel bar. Based on different error measurements, our model is favourably compared to the set of experimental results reported here and also other prediction models reported in the literature. The authors want to acknowledge Generalitat Valenciana, which has made possible this piece of research through the grant GV/2018/015.

Architectural heritage is usually built with masonry structures, which present problems under lateral in-plane loading conditions, such as wind pressure or earthquakes. In order to improve the shear behavior of masonry, the use of a fabric-reinforced cementitious matrix (FRCM) has become an interesting solution because of its synergy of mechanical properties and compatibility with masonry substrates. For a proper structural evaluation, the mechanical behavior of reinforced masonry and the FRCM itself needs to be characterized. Hence, a numerical model to evaluate the FRCM reinforcement requires some mechanical parameters that may be difficult to obtain. In this sense, the shear behavior of masonry can be evaluated by means of diagonal tension tests on small specimens (71 &times, 71 cm). In this work, a digital image correlation (DIC) monitoring system was used to control displacements and cracking patterns of masonry specimens under shear stress (induced by diagonal tension with FRCM layers) applied to one or two sides. In addition, the mechanical behavior of FRCM coupons under uniaxial tensile tests was also registered with DIC. The displacement measurements obtained by DIC were validated with the measurements registered with LVDT. Unlike LVDT-based techniques, DIC monitoring allowed us to measure deformations in masonry during the full test, detecting crack initiation even before it was visible to the eye.

Sustainability requirements are gaining importance in the construction industry, which needs to take specific measures in the design and construction of concrete structures. The use of recycled aggregates in concrete may be of special interest. Recycling a construction waste will close the life cycle of the original materials (e.g., concrete). Thus, environmental benefits would come from the lower waste generation, and from a lower necessity of raw materials for new structures. The current Spanish code for structural concrete considers the use of recycled aggregates in replacement rates up to 20% by aggregate mass, assimilating their properties with those of concretes without aggregate replacement. Higher substitution percentages would require further testing. In this work, substitution of coarse aggregate for recycled aggregates (with replacement percentages of 25%, 50% and 100%) has been studied, and the concrete&rsquo, s residual properties after exposure to high temperatures (between 350 &deg, C and 850 &deg, C) have been assessed. Compressive strength and capillary water absorption tests were made after heating, and the experiments showed higher residual strength in concretes with the greatest content of recycled aggregates. However, a statistical analysis made with additional data available in the literature seemed to predict otherwise, and the recycled aggregate replacement would have a negative effect on the residual strength.

[EN] Currently, reduction of environmental effects of the cement industry is an issue of global interest and one of the alternatives is to replace clinker with additions such as volcanic powder. The purpose of this work is to study the influence of up to 400 hardening days of volcanic powder, obtained from the last eruption of the Calbuco volcano (Chile), on the pore structure, mechanical performance, and durability-related properties of mortars which incorporate up to 20% volcanic powder as a substitution for clinker. In addition, an evaluation of greenhouse gases emissions was performed in order to quantify the possible environmental benefits of incorporating the volcanic powder in the mortars. The results obtained indicated that mortars with contents of 10% and 20% of volcanic powder had adequate service properties and improved all durability-related properties overall as compared with those noted for ordinary Portland cement. Additionally, the use of up to 20% volcanic powder makes it possible to reduce the CO2 emissions of mortars by almost 20%, demonstrating the advantages of incorporating this addition in mortars., This research was funded by the Universidad de La Frontera (Chile) (grant code DI19-0019, project entitled "Desarrollo de una dosificacion de morteros con baja conductividad termica para utilizar en prefabricados"), by the Conselleria de Educacion, Investigacion, Cultura y Deporte (at present renamed as Conselleria de Innovacion, Universidades, Ciencia y Sociedad Digital) de la Generalitat Valenciana (Spain) (grant code GV/2019/070), by the Spanish Agencia Estatal de Investigacion (grant code BIA2016-80982-R) and by the European Regional Development Fund (grant code BIA2016-80982-R).

[EN] Changes caused in the porous microstructure of ordinary Portland cement (OPC) mortars were studied using electrical impedance spectroscopy (EIS) and equivalent circuit (EqC). Two successive processes, at 20 ºC and 50 °C, consisting of several drying-rewetting cycles, were applied to the mortars. After each cycle, the electrical impedance and the amount of water absorbed were measured. The EIS-EqC methodology allowed to find two distributed impedance relaxations, associated to capillary and gel-C-S-H porosities, respectively. At room temperature any microstructural change was not detected. Nevertheless, at 50 °C two microstructural changes were inferred: 1) the volume of accessible porosity increased (pore coarsening) and 2) the surface of the conductive path through C-S-H gel became more conductive (surface smoothing)., The authors would like to thank the Spanish Ministry of Science and Innovation for supporting this research through the project BIA 2011-26947.