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The moisture content within the concrete pore network significantly influences the mechanical, thermal, and durability characteristics of concrete structures. This paper introduces a novel fully embedded wireless temperature and relative humidity sensor connected to an automatic acquisition system designed for continuous concrete monitoring. Relative humidity measurements from this new sensor are compared with those obtained by a commercial system based on the borehole method at different depths (2.5 and 4.0 cm) and exposure conditions (oven drying and humid chamber). The results allow for proving that both systems provide consistent internal relative humidity measurements aligned with the exposure conditions and highlight the capability of fully embedded wireless sensors as a practical and reliable alternative to the conventional borehole method. Additionally, the continuous monitoring of the wireless cast-in sensor exhibits reliability during unintended temperature fluctuations, emphasizing the effectiveness of permanently installed sensors in promptly detecting unintended curing variations in real time. The continuous real-time information provided combined with the practicality of these sensors might assist construction managers to improve the quality control of the concrete curing process and shrinkage behavior, and ensure the integrity of concrete surface finishing., Support from the INNOSUP Horizon 2020 Metabuilding 1st GROW/HARVEST CALL through the research project MONSEC is greatly acknowledged (Agreement Number: 370)., Postprint (published version)

The paper analyses the degradation process of commercial ultramarine blue pigments in cementitious materials. For this purpose, two commercial pigments (with and without a protective coating) in different solutions and cement pastes are studied incrementally. The results show that pigment degradation occurs due to an ion exchange phenomenon; during hydration high ion contents are released, calcium and potassium being the most aggressive for the pigment. Calcium distorts the unit cell; between the sodium of the pigment and the potassium in the medium a cation exchange phenomenon takes place. Both processes lead to the diffusion of sulphate and sulphide ions from the pigment to the medium causing loss of colour and the formation of ettringite., Peer Reviewed, Postprint (published version)

The high-performance demands on industrial floors, both in terms of larger slab dimensions and increased durability under harsh operating conditions, have led to the growing use of expansive admixtures. These generate a controlled expansive reaction within the concrete and compensate the early-age shrinkage. Despite their increasing use, calculation methods that permit to consider the expansive agents during the pavement design phase with a certain level of reliability are still unexistent. This study presents a straightforward cross-sectional model to assess both the stress-strain state and joint-opening of concrete pavements with volumetric stability admixtures by considering the slab dimensions, concrete composition, exposure conditions, and base friction characteristics. For that, a novel experimental device is designed and implemented in this work to characterize the dimensional variations associated with expansive agents since casting. A Type-G commercial volumetric stability admixture is considered as the expansive admixture. A full-scale validation of the proposed model is performed on a jointless concrete panel constructed by RCR Industrial Flooring in Spain. This validation proves the feasibility of the combined approach of laboratory calibration of the expansive addition and the cross-sectional model presented to accurately estimate both the slab deformations and joint opening developed over the 77-day test period., This research project has been supported by RCR Industrial Flooring. Thanks are extended to Juan Carlos Martín, Agustín Escámez, and Christophe Cortinovis for their assistance and collaboration throughout the course of this study. Finally, support from AGAUR through the research project EB-Pav (2021 PROD 00071) is greatly acknowledged., Postprint (published version)

Sustainability has increasingly become key in universities, as the objectives of sustainable development are essential to establish policies, guidelines and indicators that guide institutions to be more sustainable. This recognition has led many authors to develop methods to assess universities based on their performance in terms of sustainable development. This article presents a review of these methods. The review focuses on identifying existing methods and classifying the methods according to seven characteristics: (1) nature of the data, (2) data collection, (3) scope, (4) level of implementation, (5) pillars of sustainability, (6) university function, (7) country perspective taken, which will allow identifying the differences between methods when assessing sustainability. The seven criteria established for the characterization of the sustainability assessment methods contain a total of 27 sub-criteria distributed among the properties. The main contribution of the study is the analysis of the revised methods through a comprehensive characterization and systematic grouping. In the discussion, the results are examined by looking at the comprehensiveness, heterogeneity and objectivity of the methods reviewed. Together with previous research in the area, this study highlights the need to continue deepening the design of sustainability assessment methods with standardized criteria., Peer Reviewed, Postprint (author's final draft)

Interlocking Concrete Block Pavements (ICBP) are a traditional solution that has proven to work properly under varying conditions. In view of the importance of the joint filler material on the mechanical performance of this type of structure, considerable improvements have been achieved in recent years. However, these have led to a cost increase for filler materials. As a consequence, these materials tend to be placed only in the upper part of the blocks’ joints thickness, generating a non-uniform stress distribution along the thickness of the joints. In combination with direct and indirect actions, this leads to surface damages. As an alternative to filler materials, mortars can be used for block pavements. With the aim of analyzing the joints structural behavior in pavements made of precast concrete blocks, an experimental program was carried out. White slag, a local by-product, was employed as joint filler material. In mixtures, both the percentage of concrete substitution and the aggregate maximum size were varied. After the experimental program, a full-scale pilot test with pavements of precast concrete blocks was conducted. This communication presents the initial results from the experimental program conducted in the laboratory and from the pilot-test., Postprint (author's final draft)

The postcracking capacity of fiber reinforced concrete (FRC) mainly depends on the content, material, and geometry of the fibers considered. Even though the general influence of these factors on FRC behavior has been extensively addressed, the uncertainty of the FRC performance prediction along with the variability of the results still poses a challenging issue that needs to be solved to encourage the use of FRC for design and construction purposes. In this line, a database including the results of the flexural residual strength obtained from different experimental programs combined with the results of previous studies has been gathered and analyzed herein to obtain general correlations and trends providing additional information about the influence of the fibers in FRC behavior, these meant to serve for initial design stages (e.g., make decisions on the type and amount of fibers based on technical and economical requirements). The results are analyzed distinguishing between the fiber material, the fiber shape, the aspect ratio and tensile strength. The results presented herein may provide valuable information on the initial prediction of the residual strength of FRC to fully take advantage of the mechanical properties of the material., The authors from UPC wish to express their acknowledgment to the Ministry of Economy, Industry and Competitiveness of Spain for the financial support received under the scope of the projects BIA2016-78742-C2-1-R and PID2019-108978RB-C32., Peer Reviewed, Postprint (published version)

Hoy en día, es creciente la importancia que debe darse a la consideración de aspectos de sostenibilidad en el desarrollo de proyectos de infraestructuras. En concreto, la elección del material de construcción idóneo puede permitir mejorar notablemente la sostenibilidad de la estructura en términos tanto económicos, ambientales como sociales. Este artículo propone un modelo de evaluación de la sostenibilidad basado en la teoría multi-atributo para analizar diferentes alternativas de materiales para miembros estructurales. El modelo es utilizado para evaluar la sostenibilidad de distintas alternativas de cubiertas de polideportivos., Irene Josa i Culleré ha contado con la ayuda otorgada por la Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR) del Govern Català con número de referencia FI_B 00655. Por otro lado, el coautor Oriol Pons Valladares es un Profesor Serra Húnter. Además, los autores también quisieran expresar sus agradecimentos a Pilar Giraldo, Sergio Gallego y Andrés Izuzquiza, quienes han aportado recomendaciones y sugerencias, y al Ministerio Español de Economía, Industria y competitividad por el soporte económico dentro del proyecto SAES (BIA2016-78742-C2-1-R)., Postprint (published version)

In the context of the existing buildings, in recent years the concept of maintenance has changed from corrective maintenance to preventive maintenance, which is based in part on periodic inspections. There is ample evidence that preventive maintenance is more efficient than corrective maintenance, since severe deteriorations that may represent danger to people are avoided, and also money is saved. To make periodic inspections of the buildings is useful to quantify the extent to which deteriorations are severe or not, in order to facilitate decision making and prioritise therapeutic interventions. To this purpose, many scales have been used and are used to assess the degree of severity of the deteriorations in constructive elements. But it is important to say that there is no common consensus and these scales are different between them according to the study to which they belong. Thus, the main goal of this article is to propose a methodology for calculating the degree of severity of damages in buildings, which is of widespread use. This calculation method, based on one hand in a distribution of values and on the other hand in a single value (scalar), lets to calculate the severity index of systems and of the entire building, and it is easy to use and flexible., Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles, Postprint (published version)

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

Sustainability has practically become a mandatory concept to be considered in every decision, and multiple decision-making methods have been adapted to take it into account. Among them, sustainability centred methods are also known as sustainability assessments, which provides sustainability indexes to select and prioritize alternatives. One of these most recent presented techniques is MIVES, a multi attribute utility theory multi-criteria decision-making value function-based method initially developed to introduce environmental and social indicators in civil engineering design decisions and later adapted for general evaluation and prioritization of homogenous and heterogeneous alternatives. Over the last decade, it has been widely studied and applied to specific situations, but a MIVES summary is currently lacking. Therefore, in this paper MIVES literature is reviewed with a deep bibliometric analysis carried out to provide on multiple data about MIVES state-of-the-art. Furthermore, a thematic clusters categorisation is done to reveal the usefulness of MIVES as design and decision-making tool, cataloguing the wide applications of MIVES as sustainability index. Finally, a MIVES characteristics discussion is carried out to help researchers deepen their knowledge towards the method and highlight potential future research pathways., The first author acknowledges the Goverment of Spain: Ministry of Education, Culture and Sports [grant number FPU18/01471]. The second and last author wishes to recognize the support from Serra Hunter programme. Finally, this work was supported by Catalan agency AGAUR trough their research groups support program (2017SGR00227). This research is part of the R&D project IAQ4EDU, reference no. PID2020-117366RB-I00, funded by MCIN/AEI/10.13039/501100011033., Peer Reviewed, Postprint (published version)

This paper is focused on the use of mixed recycled-aggregates (RA), replacing 100% of the natural coarse aggregates, for producing steel fiber reinforced self-compacting concrete (FR-SCC-RA) oriented to the construction of foundation walls. To this end, an extensive experimental program dedicated to the mechanical characterization of FR-SCC-RA foundation walls from the material and structural level was carried out. The former was developed on both molded specimens and cores extracted from the in-situ constructed FR-SCC-RA walls in Barcelona, Spain. The results lead to confirm that the use of RA resulted satisfactorily from both the concrete manufacturing and the mechanical performance, since no affectations on the design mechanical variables (i.e., compressive and flexural tensile strengths) were detected. Likewise, the results derived from the full-scale test evidenced that the residual loads of the slabs tested were significantly higher than those calculated based on the test results of the prismatic core samples. The main outcome derived from the experimental research program is that FR-SCC-RA might be a suitable material for this structural typology and that the tested slabs presented a sufficient post-cracking residual capacity -due to the incorporation of structural fibers- for avoiding fragile failures. These conclusions could be extended to other countries where similar restrictive regulations and standards are present, regarding the use of RA and FRC for structural applications., The authors would like to thank the Agency for Management of University and Research Grants (AGAUR), Barcelona, Spain and the company ESCOFET 1886, S.A., Barcelona, Spain, for the economic support within the Industrial Doctorate Programme of Dr. Francisco Mena. This study was also fund by the Spanish Ministry of Science and Innovation under the scope of project CREEF (PID2019-108978RB-C32). Likewise, the authors wish to thank the Structure Technology Laboratory Luis Agulló Lab Staff, belonging to Barcelona Tech, Spain., Peer Reviewed, Postprint (published version)