Use of tire derived aggregate in tunnel cut-and-cover

A case-history is reported in which tire derived aggregate (TDA) was successfully applied to reduce the weight of fill upon a cut-and-cover railway tunnel. Subsequent 3D numerical analyses are used to explore the effect of different assumptions about the constitutive model of the TDA material. Alternative dispositions of TDA around the tunnel section are also examined. Reductions of up to 60% in lining bending moment may be achieved. For the case analyzed the elastic description of the TDA has little influence on tunnel lining loads, although is important for fill settlement estimates.Peer ReviewedPostprint (author's final draft

Manufacturing, Testing and Recycling of a small recyclable wind turbine blade

[EN] Thermoplastic resins are likely to replace thermoset resins in wind blade manufacturing, as their similar structural properties together with their recyclability would enable the reuse of the raw materials in other composites at the end of life. This paper presents the manufacturing, testing and recycling process of a 1 m thermoplastic composite wind turbine blade compared to a similar thermoset blade. The results showed that the static and centrifugal performance of the two blades were similar, but the thermoplastic composite blade had a lower deflection compared to the epoxy blade. The different components of the thermoplastic blade were recovered by immersion in a suitable solvent for their possible reuse in the manufacture of a new wind turbine blade. Thus, this study provides an example of the use of circular economy principles in a strategic renewable sector, wind energy, validating the use of a new thermoplastic resin in the design and recycling of wind turbine blades, without changing their current manufacturing process.Carnicero, R.; Cano, L.; Lopez-Manchado, MA.; Verdejo, R. (2022). Manufacturing, Testing and Recycling of a small recyclable wind turbine blade. Journal of Physics: Conference Series (Online). 2265(3):1-10. https://doi.org/10.1088/1742-6596/2265/3/0320131102265

A New Methodology for Bridge Inspections in Linear Infrastructures from Optical Images and HD Videos Obtained by UAV

Many bridges and other structures worldwide present a lack of maintenance or a need for rehabilitation. The first step in the rehabilitation process is to perform a bridge inspection to know the bridge′s current state. Routine bridge inspections are usually based only on visual recognition. In this paper, a methodology for bridge inspections in communication routes using images acquired by unmanned aerial vehicle (UAV) flights is proposed. This provides access to the upper parts of the structure safely and without traffic disruptions. Then, a standardized and systematized novel image acquisition protocol is applied for data acquisition. Afterwards, the images are studied by civil engineers for damage identification and description. Then, specific structural inspection forms are completed using the acquired information. Recommendations about the need of new and more detailed inspections should be included at this stage when needed. The suggested methodology was tested on two railway bridges in France. Image acquisition of these structures was performed using an UAV for its ability to provide an expert assessment of the damage level. The main advantage of this method is that it makes it possible to safely accurately identify diverse damages in structures without the need for a specialised engineer to go to the site. Moreover, the videos can be watched by as many engineers as needed with no personal movement. The main objective of this work is to describe the systematized methodology for the development of bridge inspection tasks using a UAV system. According to this proposal, the in situ inspection by a specialised engineer is replaced by images and videos obtained from an UAV flight by a trained flight operator. To this aim, a systematized image/videos acquisition method is defined for the study of the morphology and typology of the structural elements of the inspected bridges. Additionally, specific inspection forms are proposed for every type of structural element. The recorded information will allow structural engineers to perform a postanalysis of the damage affecting the bridges and to evaluate the subsequent recommendations.This research was funded by the Shift2Rail Joint Undertaking under the European Union’s Horizon 2020 research and innovation program, with grant agreement No 777630, project MOMIT, “Multiscale Observation and Monitoring of railway Infrastructure Threats”

Clarification of the slope mass rating parameters assisted by SMRTool, an open-source software

Geomechanics classifications are used to perform a preliminary assessment of rock slope stability for different purposes in civil and mining engineering. Among all existing rock mass classifications, slope mass rating (SMR) is one of the most commonly used for slopes. Although SMR is a geomechanics classification applied worldwide, often some misapprehensions and inaccuracies are made when professionally and scientifically used. Nearly all these miscalculations involve the influence of slope geometry and the dip and direction of the discontinuities. These problems can be overcome by a systematic assessment of SMR, which allows users to understand and visualize the relative orientation between discontinuities and slope. To fulfil this purpose, a complete and detailed definition of the angular relationships between discontinuities and slope are included in this paper, clarifying the assessment of the SMR parameters. Additionally, a Matlab-based open-source software for SMR (SMRTool) calculation is presented, avoiding miscalculations by automating the calculations and showing the graphical representation of slope and discontinuities. Finally, a general explanation of the method for the use of SMR is reviewed, stressing the common source of errors when applying this classification. The performance, benefits and usefulness of SMRTool are also illustrated in this paper through a specific case study.This work has been supported by the University of Alicante under the projects GRE14-04 and GRE17-11, the Spanish Ministry of Economy and Competitiveness (MINECO), the State Agency of Research (AEI) and the European Funds for Regional Development (FEDER) under projects TEC2017-85244-C2-1-P and TIN2014-55413-C2-2-P, and the Spanish Ministry of Education, Culture and Sport under project PRX17/00439 and CAS17/00392

Idoneidad de la Superintendencia de Industria y Comercio para ejercer su función de administrar justicia

Con el presente artículo de reflexión se escudriñan las razones y conceptos base que dan sustento y otorgan funciones jurisdiccionales a un órgano de la Rama Ejecutiva, como es la Superintendencia de Industria y Comercio. Aquí se expone claramente que, dentro de la división de los poderes públicos, existe una necesidad de equilibro y, transversalmente, un control, además de una colaboración armónica. Se revisan las normas que regulan las funciones de la Superintendencia, teniendo en cuenta la principialística, en torno a la división tripartita de poderes, y el propio derecho vivo, expuesto en los pronunciamientos jurisprudenciales. Con ello se logra tener una certeza fundada respecto al rol que ejerce la Superintendencia de Industria y Comercio para administrar justicia, frente a temas específicos y delimitados. Se concluye que, por la necesidad de descongestión judicial, la entidad desarrolla labores jurisdiccionales de manera idónea y legal, siempre y cuando opere bajo el debido proceso y la legalidad.Universidad Libre Seccional Pereira -- Facultad de Derecho, Ciencias Políticas y Sociales -- Especialización en Derecho Procesal, Probatorio y OralidadWith this reflection article, the reasons and basic concepts that support and grant jurisdictional functions to an organ of the executive branch, such as the Superintendency of Industry and Commerce, are scrutinized. Here it is clearly stated that, within the division of public powers, exist a need for balance and, transversely, a control, in addition to harmonious collaboration. The rules that regulate the functions of the Superintendency are reviewed, and taking into account the principle, around of tripartite division of powers, and the living law itself, exposed in the jurisprudential pronouncements. With this, it is possible to have a well-founded certainty regarding the role exercised by the Superintendency of Industry and Commerce to administer justice, in front of specific and delimited topics. It is concluded that for to the need of judicial decongestion the entity develops jurisdictionally task in a suitable and legal way

Superplastic Deformation of Alumina Composites Reinforced with Carbon Nanofibers and with Graphene Oxide Sintered by SPS—Experimental Testing and Theoretical Interpretation

The superplastic behavior of alumina-based nanostructured ceramics (Al2O3) is an important issue in the world of materials. The main body of this paper is an analysis of the creep behavior of polycrystals, with grain boundary sliding as the main deformation mechanism at high temperatures. Concomitant accommodation of grain shapes to preserve spatial continuity has a comparatively small effect on the strain rate. The constitutive equations for small deformations, relating strain and strain rate, derived from two models for grain sliding, are compared with the experimental data with their respective uncertainties. The data follow from experiments on the plastic deformation of alumina composites reinforced, on the one hand by graphene oxide, and on the other hand by carbon nanofibers sintered by SPS. The results show good agreement between experiment and theory for these advanced ceramics, particularly for one of the assumed models. The values obtained of ξ2 for model A were in the interval 0.0002–0.1189, and for model B were in the interval 0.000001–0.0561. The values obtained of R2 for model A were in the interval 0.9122–0.9994, and for model B were in the interval 0.9586–0.9999. The threshold stress was between (3.05 · 10−15–25.68) MPa.Junta de Andalucía the regional projects P18-RTJ1972 and P20-01121España Ministerio de Economía y Competitividad and Fondo Europeo de Desarrollo Regional funds through the projects MAT2015-71411-R and RTI2018-099033-B-C33Universidad de Sevilla “VI Plan Propio de Investigación y Transferencia-US 2017España Ministerio de Ciencia, Innovación y Universidades The projects PGC2018-094952-B-I00 (MCIU/AEI/FEDER, UE) and PID2019- 103847-RJ-I0

Empleo de drones (RPAS) para la elaboración de material audiovisual docente en asignaturas de Ingeniería Civil

El presente trabajo estudia la utilización de drones telecomandados de uso comercial (RPAS) para producir material audiovisual específico de diversas asignaturas de las titulaciones de Ingeniería Civil. Se trata de un equipamiento de alta tecnología y coste relativamente asequible, en torno a 1.300 euros, para producir material audiovisual que hasta ahora únicamente podría ser obtenido empleando medios mucho más limitados (fotografías aéreas y de satélite) o mucho más costosos, tales como vuelos fotográficos específicos. De este modo, se valorará la viabilidad de introducción de una nueva herramienta tecnológica de innovación educativa hasta ahora no empleada en la elaboración de material docente, analizando sus principales ventajas y limitaciones

New Approaches for Teaching Soil and Rock Mechanics Using Information and Communication Technologies

Soil and rock mechanics are disciplines with a strong conceptual and methodological basis. Initially, when engineering students study these subjects, they have to understand new theoretical phenomena, which are explained through mathematical and/or physical laws (e.g. consolidation process, water flow through a porous media). In addition to the study of these phenomena, students have to learn how to carry out estimations of soil and rock parameters in laboratories according to standard tests. Nowadays, information and communication technologies (ICTs) provide a unique opportunity to improve the learning process of students studying the aforementioned subjects. In this paper, we describe our experience of the incorporation of ICTs into the classical teaching-learning process of soil and rock mechanics and explain in detail how we have successfully developed various initiatives which, in summary, are: (a) implementation of an online social networking and microblogging service (using Twitter) for gradually sending key concepts to students throughout the semester (gradual learning); (b) detailed online virtual laboratory tests for a delocalized development of lab practices (self-learning); (c) integration of different complementary learning resources (e.g. videos, free software, technical regulations, etc.) using an open webpage. The complementary use to the classical teaching-learning process of these ICT resources has been highly satisfactory for students, who have positively evaluated this new approach.This work has been developed in the framework of the RECLAND Project. It has been funded by the European Union under Lifelong Learning Programme, Erasmus Programme: Erasmus Multilateral Projects, 526746-LLP-1-2012-1-ES-ERASMUS-EMCR, MSc Programme in Climate Change and Restoration of Degraded Land

Digital 3D Rocks: A Collaborative Benchmark for Learning Rocks Recognition

Naked eye rock recognition is an essential activity for professionals and students of geosciences, architecture and engineering. Through a hand holding rock specimen, it is usually required not only to identify the type of rock but recognize their texture and understand its expected properties mechanical and petrophysical properties. Although a wide choice of books, websites and apps are available in the literature and on the Internet, their contents are two-dimensional (2D) and static. Nowadays, the application of remote sensing techniques such as Light Detection and Ranging (LiDAR) or Structure from Motion (SfM) enable the generation of three-dimensional (3D) interactive models, which are here presented as a novel perspective of learning and practising rocks recognition. Despite limitations of the technique, 3D digital models of rocks permit their virtual visualization and manipulation to reveal parts of the specimens that are hidden in the 2D photograph, as well as details of the rock specimen’s texture such as grain and minerals size, distribution and organization along with the possibility of identifying petrological features, foliation, mineral orientations and others. This provides a novel perspective of learning and practising rocks identification. Herein, a benchmark of digital rocks collected all around the world and generated using SfM technique is presented. The rocks are organised using a straightforward classification system based on the texture jointly with a detailed description to aid the specimen recognition. A behavioural geomechanical classification is then applied. Moreover, a linked datasheet shows the engineering classification, the weathering degree, the guide physical and mechanical properties (general, and specific when available), the engineering uses and others. The information is organised on an open-access website hosted by the University of Alicante (https://web.ua.es/digitalrocks). This initiative also aims to encourage students and professionals to generate their own models and to provide the description to enlarge the repository.This work was partially funded by the University of Alicante (vigrob-157 Project, GRE14-4, GRE15-19 and GRE17-011 Projects), the Spanish Ministry of Economy and Competitiveness (MINECO) and EU FEDER under Projects TIN2014-55413-C2-2-P and TEC2017-85244-C2-1-P. Authors thank Ignacio Pérez-Rey/ Leandro Alejano for the description some used samples