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Robustness Interpretation of Intact and Damaged Framed Structures
No full textThis paper addresses the concept of structural robustness in buildings, particularly focusing on progressive collapse, a phenomenon where localized damage leads to widespread structural failure. Resilient buildings are designed to maintain adequate performance during unexpected extraordinary events, such as explosions, impacts, or earthquakes, yet defining "adequate" performance remains complex. Design codes often refer to the "proportion" between accidental events and their consequences, highlighting the need for a deeper understanding of progressive collapse. This collapse occurs through a series of failures in structural elements, such as beams and columns, which trigger a dynamic load redistribution and result in a catastrophic domino effect. Examples of progressive collapse, such as the Ronan Point Building collapse in 1968 and the World Trade Center collapse in 2001, have driven research and regulatory efforts in this field.
While strengthening all structural elements could improve a building's damage tolerance, this approach is costly. Alternative strategies, such as redundancy and compartmentalization, are commonly used, but their effectiveness is still debated. Similarly, although anti-seismic design enhances progressive collapse resistance, it does not represent the optimal strategy for maximizing resistance. This study emphasizes the limitations of current design codes and the need for improved analytical models of progressive collapse.
The paper introduces a new simulation method based on the Discrete Element Method (DEM) to conduct large-scale parametric studies. This approach is used to identify collapse mechanisms and develop kinematic models to analyze and generalize simulation results. By extending the P-Δ method to both intact and damaged structures, simplified formulas are derived for calculating collapse loads and progressive collapse resistance. The methodology is applied to investigate the progressive collapse of 2D reinforced concrete frames subjected to the sudden removal of beams and columns. The findings highlight the importance of designing structures that can redistribute and dissipate loads, utilizing the ductility of components to avoid fragile failure behavior.
Robustness Interpretation of Intact and Damaged Framed Structures
EUR ING Alessandro Calv
CHAPTER 20: FAST WARMING AND LOW ENERGY CONSUMPTION
No full textMany manufacturing processes for composite material structures are based on large and expensive facilities that result in slow, expensive, and energy-inefficient processes. The preforming of dry fiber fabrics, for example, is carried out in large hot drape forming facilities, where conventional heating sources based on infrared lamps are not very efficient, since much of the heat supplied is transferred to the heavy aluminum molds in which the preforming process is carried out. In the current context in which it is essential to reduce the carbon footprint of each component, it is essential to reduce the energy needed in production processes and at the same time achieve competitive cycle times.
In this context, Tecnalia has been working for years on the direct resistive heating technology in order to accelerate and optimize composite material manufacturing processes. The direct application of a current to the carbon fiber material to be processed has the advantage of avoiding the heating and cooling of the molds or other adjacent tools, obtaining the results much more quickly and efficiently than with the methods used until now. In the case, for example, of the preforming process of carbon fabrics, applying heat only to the preform allows reducing cycle times and energy consumption by more than 60% and 80% respectively. This means reducing the cost of the process related to lower energy consumption and shorter cycle time. The quality of the preforms obtained through resistive preforming is the same to that obtained through conventional hot drape forming technology and, in addition, it is a repetitive process that has been validated in industrial manufacturing environment.
The article also indicates that this direct resistive heating technology is not only applicable in carbon fiber preforming processes but could also be used in other manufacturing processes for composite material components
CHAPTER 17: VITRIMERS
No full textThe development of recyclable plastics is a key focus of research in the current world due to its environmental issues and concerns about non-renewability. Recently, vitrimeric materials have garnered significant attention as an exciting class of renewable plastics due to their potential to exhibit strength, durability, and chemical resistance approaching that of traditional thermosetting plastics, while also demonstrating recyclability at the end of their lifespan. This is attributed to their chemical structure, as vitrimers possess dynamic covalent crosslinking, providing them with stability while being reprocessable. This review summarizes the latest advancements and prospects in the development of vitrimeric materials. Special emphasis is placed on vitrimer design strategies that pave the way for the development of next-generation circular materials. The emerging applications of vitrimers are also discussed in terms of their properties, including self-repair, malleability, processability, and multiple shape memory
CAPÍTULO 5: IDENTIFICACIÓN DE LOS COMPOSITES PARA SU RECICLADO
No full textCurrently, there is a growing interest in the development of reusable polymer matrix composite materials. In this regard, it is commonly known that although thermoplastic matrices can be reprocessed, they generally have worse mechanical properties, and their processing is much more complex than that of thermoset matrices, due to the high viscosities involved during manufacturing processes [1]. Therefore, the development of new thermoset matrices that can be reused is key. In this context, solutions such as polymers based on dynamic covalent bonds emerge, which allow the material to be reprocessed by heating it above its Tg [2], as seen in previous chapters. This would allow reprocessing similar to that of thermoplastic polymers, enabling these composite materials to be used again for new applications.
Therefore, considering the development of these new materials and the existing concerns about developing more sustainable manufacturing techniques and materials, the need arises to establish new methods for the proper identification of both the composite material waste generated and those composite materials that are recycled, i.e., those that are reused. Products can be labeled to facilitate better recovery at the end of their useful life (End of Life, EOL), especially due to the wide variety of possible material compositions in composite materials. Labeling is mandatory for certain plastic products in the automotive industry (including composite materials) according to the End-of-Life Vehicle (ELV) directive [3]. There are standards for labeling products in other sectors. Some high-value products in the aerospace and automotive industries now incorporate Radio Frequency Identification (RFID) tags for tracking product life cycle management (Product Life Management, PLM) and ensuring provenance and traceability. These tags may contain data about the material to facilitate higher-value recycling and could be linked to virtual databases that include material origin, manufacturing, and usage data throughout the entire life cycle.
Proper identification of components can also be done through the Digital Product Passport proposed as part of the ESPR (Ecodesign for Sustainable Products Regulation) [4], to maintain adequate traceability of products in terms of material technical characteristics, repair information, etc., so that consumers have a complete understanding of the materials and their environmental impact, in order to establish appropriate reuse techniques. The ESPR, in turn, aims to design components that result in more reliable, durable, reusable, repairable, easy-to-maintain, recyclable, and energy-sustainable products.
In addition, waste can be classified using EWC codes (European Waste Catalogue). This can enable proper identification of waste that may be more hazardous or waste that could be reused at the end of its first life cycle.
Therefore, this chapter aims to address, in a simple manner, those methods for identifying composite materials, both focused on the traceability of products through digital passports, and for managing the waste generated during their service life using EWC codes
CHAPTER 4: LIFE CYCLE ASSESSMENT METHODOLOGY
No full textLife Cycle Assessment (LCA) of composite materials is the use of a systematic approach to assess environmental impacts throughout all stages of the life cycle. This methodology includes defining the objectives and scope of the study, data collection, impact assessment and interpretation of results. This chapter presents the specific considerations for the LCA of composite materials, analyzing related works on this topic. It is concluded that most of the work published to date uses LCA as a tool for comparative studies between traditional solutions (mostly metallic structures) and lightweight composite solutions. The authors observe that there has also been an increase in the use of green or bio-based composites in the recent years, made from natural fibers and/or resins.
 
A l’avantguarda en informació de sostenibilitat, transparència ESG i compliance amb la legislació europea. Una oportunitat per a les universitats catalanes. Full Paper
No full textEls reptes presents s’emmarquen en una conjuntura d’emergència climàtica i pobresa global, i calen accions de tots els actors de la societat per afrontar aquests desafiaments fent un pas endavant cap a una economia més sostenible. Ens situem a la tercera dècada del segle XXI i l’entorn BANI Brittle (Fràgil), Anxious (Anciós), Nonlinear (No lineal), Incomprehensible (incompressible) caracteritza la conjuntura mundial post-pandèmia (Nataliia & Olena, 2023). Les organitzacions tendeixen a posicionar la sostenibilitat com a element clau en la seva estratègia empresarial, en part, a conseqüència d’importants desenvolupaments legislatius, però també per respondre a la crisi climàtica. Assistim a dia d’avui a la consolidació de normes que desenvolupen i obliguen a vetllar pel compliment dels 17 objectius de desenvolupament sostenible (ODS) de 2015, i el Pacte Verd Europeu de 2019 n’és el full de ruta a Europa: un paquet de mesures ambiciós que pretén que ciutadania i empreses europees es beneficiïn d’una transició verda sostenible i es marca assolir la neutralitat climàtica d’aquí a vint-i-cinc anys. I en aquest marc, prenen rellevància els criteris ESG, fent referència al respecte a qüestions mediambientals derivades de l’activitat empresarial (Environment), als drets de caràcter social de les persones afectades d’aquesta activitat empresarial desenvolupada (Social), i a l’acompliment d’un bon govern corporatiu (Governance) i la seva transparència. Les qualificacions ESG s’estan convertint en índex de referència en la presa de decisions d’inversió, i l’acadèmia els estudia per a diversos sectors econòmics, però poc sovint parant atenció a la relació ESG - universitat. 
Análisis de diez años de tipos de interés convulsos: entidades financieras e inversores
Get PDFEstudio sobre la influencia de la reciente subida de tipos de interés en los resultados de la actividad bancaria, en lo que respecta a su cuenta de resultados, así como a diferentes ratios, loan-to-deposits, Liquidity Coverage Ratio, ROA, ROE, CET1 y ratio de apalancamiento, así como la evolución de personal bancario, número de oficinas y número de personas por oficinas entre los años 2008 y 2023.
También se ha analizado el efecto de las subidas de tipos de interés del BCE sobre los depósitos bancarios, así como ante la reducida traslación de efecto contagio en tipos de interés para clientes la búsqueda de alternativas por parte de los clientes adquiriendo masivamente Letras del Tesoro y otros productos financieros desintermediados.
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Study on the influence of interest rates on the results of banking activity, with regard to its income statement, as well as different ratios, such as loan to deposits, liquid coverage, ROA, ROE, common equity, TIER 1 CET and effect of deleveraging, as well as the evolution of banking personnel, number of branches and number of people per branch between the years 2008 and 2023.
The effect of the ECB's interest rate increases on bank deposits has also been analyzed, as well as the reduced contagion effect transfer in interest rates for clients, the search for alternatives by clients massively acquiring Treasury Bills and other disintermediated financial products
Impacte econòmic en el territori dels Ajuts d'Inversió LEADER en el marc del Programa de Desenvolupament Rural de Catalunya 2014 – 2022: Balanç inversions 2016 – 2020.
No full text''La present comunicació té per objecte avaluar l’impacte econòmic en el món rural català de les inversions executades a través de la iniciativa LEADER (Liaison Entre Actions de Développement de l'Économie Rurale) de la Unió Europea, en el marc del Programa de Desenvolupament Rural de Catalunya en el període comprés entre els anys 2016 i 2020. L’impacte econòmic generat per les inversions amb ajuts LEADER s’ha avaluat en termes de producció bruta total, en termes de Valor Afegit Brut (VAB), en termes de llocs de treball mitjançant Unitats de Treball Equivalents (UTE), i en termes de retorn fiscal via Impost sobre la Renda de les Persones Físiques (IRPF), Impost de Societats (IS) i Impost sobre el Valor Afegit (IVA), i tenint en compte dos tipus d’impacte: un impacte puntual i un impacte recurrent en el temps.'' A partir d’una anàlisi d’impacte econòmic ex post, la present avaluació posa el focus en la quantificació del grau d’efectivitat i impacte econòmic real d’una política pública concreta. Paraules clau Avaluació de polítiques públiques, LEADER, Impacte econòmic, taula input output, món rural, Grup Acció Loca