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Shear strength assessment of reinforced concrete components containing EAF steel slag aggregates
Get PDFElectric Arc Furnace (EAF) slag can be reused as aggregate in Portland cement concrete mixes. The addition of EAFS and other waste co-products (fly ash, blast furnace slag) will modify the binding properties and will, importantly, enhance the global sustainability of such concretes. These mix designs offer acceptable pumpability and self-compaction in the fresh state and can be reinforced with fibers. In this study, eight different concrete mixes are designed within the range of medium-strength concretes (30–50 MPa) and are characterized in both the fresh and the hardened state. Large concrete volumes are used to pour reinforced beams, which are then subjected to small-span high-load tests to evaluate their resistance to shear stress, by analyzing two types of transversal (shear) reinforcement. The tests yielded promising results, contributing additional evidence on the viability of using recycled EAFS aggregate in structural applications. The mechanical behavior of these concretes was closely correlated with the strength predictions calculated with the formulas listed in various international standards.Spanish Ministry of Universities, MICINN, AEI, EU and ERDF [PID2020-113837RB-I00; RTI2018-097079-B-C31; 10.13039/501100011033; FPU17/03374]; the Junta de Castilla y León and ERDF [UIC-231, BU119P17]; Youth Employment Initiative (JCyL) and ESF [UBU05B_1274]; the University of Burgos [grant number SUCONS, Y135.GI], and, finally, our thanks also go to the SAREN research group (IT1619-22, Basque Government)
Hydrostatic pressure dependence in tensile and compressive behavior of an acrylonitrile–butadiene–styrene copolymer
Get PDFThe strain-rate dependence of a commercial grade ABS copolymer has been analyzed in both compression and tension. By measuring in two loading geometries, the hydrostatic pressure-dependence on the material's deformation behavior can be established. An alternative method to determine pressure-dependence, based on the difference in strain-rate dependence for various loading geometries, has been presented. It was shown to be an effective technique, both for thermorheologically simple materials such as ABS, as well as thermorheologically complex materials, for example, PMMA. A yield criterion, based on an Eyring-type pressure-modified rate equation, has been compared to finite element simulations using the Eindhoven Glassy Polymer (EGP) constitutive model. Although both methods give quantitatively similar results for the yield stress prediction, only the fully 3D EGP model is able to represent the large-strain deformation behavior.Spanish Government (Ministry of Science and Innovation, Ministry of Economy and Competitiveness) through grant numbers RYC- 2010-07171, DPI2011-25470, and PID2019-106518RB-I00 is gratefully acknowledged
Carbon nanomaterials with Thymol + Menthol Type V natural deep eutectic solvent: From surface properties to nano-Venturi effect through nanopores
Get PDFA theoretical study using Density Functional Theory and classical Molecular Dynamics simulations for the
study of carbon nanomaterials in archetypical Menthol + Thymol Type V Natural Deep Eutectic Solvent is
reported. The nanoscopic structure of the representative nanofluid is analyzed considering confinement,
adsorption and solvation effects, as well as consequences on diffusion properties through nano pores.
Different types of nanomaterials were considered such as fullerenes, nanotubes, graphene and nanopores.
The study of nanoscopic properties allowed to analyze the response of the solvent to the presence of the
nanomaterials, taking into account solvent rearrangement and confinement in nanocavities and surfaces.
This response shows liquid structure and mobility consequences, with a sort of nano-Venturi effect
among them. The reported results provide for the first time a characterization of this type of natural solvents as a sustainable platform for the development of carbon – nanomaterials-based technologies.This work was funded by Junta de Castilla y León (Spain, project NANOCOMP - BU058P20), European Union H2020 Program (H2020-NMBP-TO-IND-2020-twostage-DIAGONAL-GA- 953152) and Ministerio de Ciencia, Innovación y Universidades (Spain, project RTI2018-101987-B-I00). We also acknowledge SCAYLE (Supercomputación Castilla y León, Spain) for providing supercomputing facilities. The statements made herein are solely the responsibility of the authors
Efecto del postprocesado mediante HIP a 850ºC / 200 MPa en el comportamiento a fatiga de la aleación Ti-6AI-4V fabricada mediante SLM
Get PDFComunicación presentada en: 5th Iberian Conference on Structural Integrity que corresponde con el 38 Congreso del Grupo Español de Fractura GEF2022 celebrado en Coimbra, Portugal del 30 de marzo al 1 de abril de 2022Hot Isostatic Pressing (HIP) es una técnica de postprocesado termomecánico ampliamente utilizada en piezas fabricadas mediante Selective Laser Melting (SLM) para densificar el material y reducir los defectos internos intrínsecos que se originan durante la fabricación, como porosidad o la falta de fusión, los cuales tienen un gran impacto en la resistencia a fatiga del material. En este trabajo se presenta el efecto de un ciclo HIP, realizado a una presión de 200 MPa y una temperatura de 850ºC durante 2 horas, sobre el comportamiento a fatiga de una aleación Ti-6Al-4V fabricada por SLM. Se ha efectuado un análisis defectológico y microestructural de las diferentes situaciones analizadas (SLM as-built,
SLM+HIP, material de referencia) con el objetivo de estudiar la relación de los defectos y la microestructura con la vida en fatiga. Los resultados muestran que el presente proceso de HIP permite una muy buena densificación del material, y permite obtener una microestructura con mínimos efectos de engrosamiento de la fase α, lo cual se traduce en unas buenas propiedades de fatiga comparables a las del material de referencia.Hot Isostatic Pressing (HIP) is a thermo-mechanical post-processing technique widely used to reduce the internal defects characteristic of additive manufacturing techniques (lack-of-fusion or entrapped-gas-pores), which have a great impact on the fatigue properties of the material. In this work, the effect of a HIP-cycle at a pressure of 200 MPa and a temperature of 850ºC for 2 hours, on the fatigue behaviour of a Ti-6Al-4V alloy manufactured by SLM is presented. Microstructural and fractographic analysis for the different conditions (SLM as-built, SLM+HIP, reference material) have been carried out in order to study the effect of defects and microstructure features on the fatigue life. The results indicate that the present HIP process allows a very good densification of the material and exhibiting a microstructure with minimal alpha-phase coarsening effects, obtaining good fatigue properties comparable to the reference material ones.Los autores desean agradecer la financiación recibida a través del proyecto de la JCyL referencia BU-002-P20, cofinanciada con fondos FEDER
Dataset of the academic impact of the Camino de Santiago
No full textThe present dataset contains two complementary databases to analyse the scientific impact of the Camino de Santiago in the academic literature. On the one hand, we have included a database extracted from Scopus with indexed manuscripts directly related to the Camino de Santiago. On the other hand, we also present a database of international doctoral theses also directly related to the Camino de Santiago.
The dataset includes not only the final processed database but also the raw file from the Scopus search. A process of harmonisation of keywords, keywords+ and institutions has been performed on the original query. The files used to achieve the harmonisation are also included in the dataset.The authors are grateful for the support and funding from the Ministry of Science and Innovation through its networks of excellence HAR2017-90883-REDC and RED2018-102518-T) and the project PID2020118906GB-I00, and from the Junta de Castilla y León - Consejería de Educación (BDNS 425389). Also, this work has been partially funded by the European Social Fund, through the grant of Silvia Díaz de la Fuente's predoctoral contract through the Consejería de Educación de la Junta de Castilla y León.v.
(Des)cortesía en el aula de ELE: la dicotomía tú/usted y sus implicaciones pragmáticas en los rusohablantes en Estonia
Get PDFAprender una lengua no debe basarse solo en memorizar vocabulario y gramática, sino que también se debe aprender a usar la lengua de manera adecuada en cada situación, lo cual es estudiado por la pragmática. De transferir las reglas pragmáticas de la L1 al español, es posible que los aprendientes sufran lo que se denomina interferencia pragmática, ya que no todos los actos de habla se realizan igual en todas las culturas o lenguas. Un claro ejemplo de esto es el uso de los pronombres T/V. Después de un periodo de observación a un grupo de aprendientes rusohablantes dentro del estrato bilingüe de Estonia en Bachillerato Internacional, se puso de manifiesto que no usaban esta distinción de la misma forma que un nativo hispanohablante. Para este trabajo, después de realizar una encuesta previa de uso de estos pronombres en ambas lenguas, se diseñó una secuencia didáctica basada en la metodología del extrañamiento y usando escenas de series de televisión españolas con el objetivo de que los alumnos interiorizaran el uso correcto de esta dicotomía y aprendieran a desenvolverse correctamente en conversaciones básicas de situaciones formales e informales. Los grupos de aprendientes que participaron en este trabajo están divididos en el grupo de control y el de la investigación. La unidad didáctica se implementó en el grupo de la investigación y se hicieron pruebas a ambos para comprobar los resultados. Este estudio pretende ser un ejemplo de estudio pragmático en ELE que puede llevarse a cabo con hablantes de lenguas eslavas, cuyas expectativas pragmáticas son similares.Learning a language should not only be based on memorizing vocabulary and grammar, but also learning how to use the language in each communicative exchange should not be disregarded, which is what pragmatics studies. Due to a negative transfer of the pragmatic rules of the L1 to the L2, students might experience a pragmatic interference, since not every speech act is performed the same way in every culture or language. A clear example of this is the use of the T/V pronoun dichotomy. After an observation period of a group of Russian-speaker learners within the bilingual sphere of Estonia and in the system of the International Baccalaureate, it was clear that they could not use this distinction the same way as a native Spanish speaker. For this paper, after delivering a survey on the use of these pronouns in both languages, a didactic unit was designed based on the methodology of the estrangement and using scenes from Spanish TV shows, under the objective of the students assuming the correct use of these pronouns and learning how to effectively communicate in basic exchanges in formal and informal situations. The group of learners who participated in this investigation were divided into the control group and the research group. The didactic unit was implemented only in the research group and tests were delivered to both groups in order to compare the results. This investigation aims at being an example of how a pragmatic study in Spanish as a Foreign Language could be carried out with Slavic-languages speakers, whose pragmatic expectations are similar
A New Measure for Serious Games Evaluation: Gaming Educational Balanced (GEB) Model
No full textSerious games have to meet certain characteristics relating to gameplay and educational
content to be effective as educational tools. There are some models that evaluate these aspects, but
they usually lack a good balance between both ludic and learning requirements, and provide no guide
for the design of new games. This study develops the Gaming Educational Balanced (GEB) Model
which addresses these two limitations. GEB is based on the Mechanics, Dynamics and Aesthetics
framework and the Four Pillars of Educational Games theory. This model defines a metric to evaluate
serious games, which can also be followed to guide their subsequent development. This rubric
is tested with three indie serious games developed using different genres to raise awareness of
mental illnesses. This evaluation revealed two main issues: the three games returned good results for
gameplay, but the application of educational content was deficient, due in all likelihood to the lack of
expert educators participating in their development. A statistical and machine learning validation
of the results is also performed to ensure that the GEB metric features are clearly explained and the
players are able to evaluate them correctly. These results underline the usefulness of the new metric
tool for identifying game design strengths and weaknesses. Future works will apply this metric to
more serious games to further test its effectiveness and to guide the design of new serious games.This research was partially funded by the ACIS project (Reference Number INVESTUN/21/BU/0002) of the Consejería de Empleo of the Junta de Castilla y León (Spain) and the Ministry of Science, Innovation and Universities (FPU18/04688)
The energy threshold in dynamic probing
Get PDFIn dynamic probing tests, penetration is closely related to the potential energy of the hammer (nominal energy). This energy
stems from the mass and free fall of the hammer after being released from a certain height. Penetration depends on energy,
although only on a portion of that nominal energy that is effectively transferred to the rods (ENTHRU) and, more precisely,
the energy that reaches the cone (ENTHRUcone). ENTHRU can be measured by monitoring the upper part of the drive rods.
To calculate ENTHRUcone, ENTHRU needs to be corrected in three ways. Firstly, the energy loss in the energy transmission
through the rods has to be subtracted, as well as the energy loss due to the skin friction of the rods along the soil around
them. It is also necessary to add the energy due to the rod weight penetrating the soil. The main hypothesis assumed and later
experimentally proved in this paper is based on the fact that ENTHRUcone has to be greater than a certain value or minimum
energy (energy threshold: Th) in order to be able to cause penetration. After analyzing more than one hundred blows with
different hammer mass and drop height, a small but consistent Th and a linear relationship between energy and penetration
beyond it were found. The energy that really produces penetration (ENPEN) will be ENTHRUcone, minus Th. This allows for
improved energy corrections and correlations between results from various kinds of penetration tests.The writers would like to express their gratitude to the University of Burgos, the University of Cantabria, and Sondeos del Norte, S.A. and especially to José Manuel Sánchez Alciturri, the mastermind of this research