17 research outputs found
Transfert transatlantique des hépatites fulminantes vers un centre de transplantation hépatique
No full textObjectif : rapporter notre expérience et préciser le devenir des patients atteints d’hépatites fulminantes. Méthodes : analyse rétrospective monocentrique incluant tous les patients ayant présenté une hépatite fulminante hospitalisés au CHU de Martinique entre 2007-2016 ; expression des résultats en moyenne ± SD ou %. Résultats : En 9 ans, 36 patients ont été hospitalisés dans notre hôpital pour hépatite fulminante dont 11 par le paracétamol et 8 d’origine indéterminée. L’âge moyen était de 49±13 ans, avec 21 hommes et 15 femmes. Le score IGS2 était de 24 +/- 11. Vingt-sept patients ont reçu du N- acétylcystéine (NAC) ou un traitement spécifique en rapport avec l’étiologie. Vingt-cinq patients ont présenté un syndrome de défaillance multivicérale dont 21 dans le groupe non transféré. Dix-neuf patients ont bénéficié d’un avis de centre référent, 9 ont été transférés et 3 transplantés (2 intoxications au paracétamol et 1 hépatite auto immune). Pour les patients transférés, l’âge moyen était de 39±7 ans, l’étiologie était principalement une intoxication au paracétamol (6 sur 9). La survie était de 66% pour la population générale, quatre décès sont secondaires à un syndrome de défaillance multiviscérale, deux sont dus à un choc hémorragique et un à une hypertension intracrânienne. Trois patients sont décédés avant ou pendant le transfert. Une limitation/arrêt des thérapeutiques a été décidé chez 2 patients compte tenu des comorbidités. L’absence d’administration de N-acétylcystéine (NAC), la présence de SDMV et une encéphalopathie hépatique sévère à la prise en charge étaient des facteurs liés significativement au décès. Conclusion : La survie des patients présentant une hépatite fulminante est améliorée par la collaboration avec un centre spécialisé, un transfert précoce et l’administration de NAC
Interaction of geometric and material nonlinearities in stainless steel frames
No full textAdequate mechanical properties make stainless steel an excellent construction material for structures. The current stainless steel European structural code EN1993-1-4 (2015) is largely based on provisions given for carbon steel EN1993-1-1 (2005) and does not establish specific design rules for the global analysis of stainless steel structures. Thus, the same classification criterion applies in both codes for sway and non-sway structures, as well as providing the same predicting expressions for the amplification of bending moments in basic structures, despite the considerable differences between the mechanical behaviour of these two materials. However, recent numerical research on stainless steel frames with H cross-sections by Walport et al. (2019) showed that the degradation of stiffness due to material nonlinearities considerably affects the response of stainless steel frames, causing greater deformations and increasing second order effects. In order to contribute to the optimal design of stainless steel structures, this paper investigates the influence of the nonlinear material response of stainless steel alloys on frame-type structures with Rectangular Hollow Sections based on the experimental results conducted by Arrayago et al. (2019), and the interaction of material and geometric nonlinearities.The authors acknowledge the funding from MINECO (Spain) under Project BIA2016-75678-R, AEI/FEDER, UE “Comportamiento estructural de pórticos de acero inoxidable. Seguridad frente a ac-ciones accidentales de sismo y fuego”. The first author would also like to acknowledge the financial support provided by FPI-MINECO PhD fellowship Ref. BES-2017-082958. The second author would like to acknowledge the financial support received funding from the European Union’s Horizon 2020 research and innovation pro-gramme under the Marie Sklodowska-Curie grant agreement No. 842395.Postprint (published version
The Continuous Strength Method for the design of stainless steel members under combined loading
No full textThe Continuous Strength Method (CSM) provides accurate cross-section resistance predictions since allowance is made for the partial spread of plasticity and the beneficial effects of strain hardening. Although CSM design provisions for different loading conditions are available, the method was limited to the determination of cross-sectional resistance until recent research by Arrayago et al. (2020) proposed a consistent new approach to the design of stainless steel hollow section members subjected to compression. Extension of the CSM to the design of stainless steel members subjected to combined compression and bending moment is presented in this paper. The analysis is based on numerical results generated in the current study and existing results collected from the literature on stainless steel hollow section members. The results demonstrate that the adoption of the CSM design equations to predict column strength considerably improves the ac-curacy of the calculated beam-column capacities. The reliability of the proposed approach is demonstrated through statistical analyses performed in accordance with EN 1990.The authors acknowledge the funding from the MINECO (Spain) under Project BIA2016-75678-R, AEI/FEDER, UE “Comportamiento estructural de pórticos de acero inoxidable. Seguridad frente a acciones accidentales de sismo y fuego”. The first author would also like to acknowledge the financial support received from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 842395.Postprint (published version
Influence of Welded Joints Modelling on the Structural Response of Steel Frames under Fire Situation
No full textSteel frames with compact cross-sections usually fail describing a plastic failure mechanism, redistributing internal forces. In order to fully form a plastic failure mechanism, the designed joints must be able to withstand the increase in stresses resulting from the redistribution of internal forces and to provide enough stiffness to prevent large second order effects. According to current European codes, full-strength joints can be modelled as perfectly rigid joints and for structures with Class 1 cross-sections carrying out a plastic analysis is allowed. Both of these statements have been widely studied at room temperature but whether these assumptions are valid under fire situation needs to be assessed yet. With this goal in mind, this paper presents a numerical study comparing the response of steel frames for which the welded joints between members are accurately modelled with the results for frames with perfectly rigid joints, both at room temperature and at elevated temperatures. The obtained results show that modelling full-strength joints as perfectly rigid joints for numerical purposes can also be done under fire situation without major differences in the structural response. Moreover, all the analysed Class 1 frames could form a fully plastic mechanism under fire situation.The first author acknowledges the support of the Secretaria d’Universitats i Recerca de la Generalitat de Catalunya (Spain) and the European Social Fund. The authors acknowledge the funding from the MINECO (Spain) under Project BIA2016-75678-R, AEI/FEDER, UE “Comportamiento estructural de pórticos de acero inoxidable. Seguridad frente a acciones accidentales de sismo y fuego”.Peer ReviewedPostprint (published version
Flexural response of multi-stiffened aluminium beams in dock platforms
Get PDFIn this paper, the flexural response of extruded wrought aluminium girders is presented. This structural element is intended for usage in marine structures such as light docks, marinas and yacht ports. Ease of use, durability, reduced weight, manoeuvrability and the potential development of bespoke sections are appealing properties in such structures that are fulfilled satisfactorily by this type of aluminium elements. Both experimental and numerical analyses are presented. Experimentally, modules of the girders are tested with loading about both minor and major axes. Numerically, the tests are satisfactorily reproduced for the sake of validation and a subsequent exploitation of the model is addressed for further study of the structural response of the girders. A discussion of the results is presented with some design recommendations of these particular structural elements.Peer ReviewedPostprint (author's final draft
Flexural response of multi-stiffened aluminium beams in dock platforms
No full textIn this paper, the flexural response of extruded wrought aluminium girders is presented. This structural element is intended for usage in marine structures such as light docks, marinas and yacht ports. Ease of use, durability, reduced weight, manoeuvrability and the potential development of bespoke sections are appealing properties in such structures that are fulfilled satisfactorily by this type of aluminium elements. Both experimental and numerical analyses are presented. Experimentally, modules of the girders are tested with loading about both minor and major axes. Numerically, the tests are satisfactorily reproduced for the sake of validation and a subsequent exploitation of the model is addressed for further study of the structural response of the girders. A discussion of the results is presented with some design recommendations of these particular structural elements.Peer Reviewe
The Continuous Strength Method for the design of stainless steel hollow section columns
Get PDFThe Continuous Strength Method (CSM) provides accurate resistance predictions for both stocky and slender stainless steel cross-sections; in the case of the former, allowance is made for the beneficial effects of strain hardening, while for the latter, design is simplified by the avoidance of effective width calculations. Although the CSM strain limits can be used in conjunction with advanced analysis for the stability design of members, for hand calculations, the method is currently limited to the determination of cross-sectional resistance only, i.e. member buckling resistance is not covered. To address this limitation, extension of the CSM to the design of stainless steel tubular section columns is presented herein. The proposed approach is based on the traditional Ayrton-Perry formulation, but features enhanced CSM cross-section resistances and a generalized imperfection parameter that is a function of cross-section slenderness. The value of the imperfection parameter increases as the slenderness of the cross-section reduces to compensate for the detrimental effect of plasticity on member stability that is not directly captured in the elastic/first yield Ayrton-Perry approach. The accuracy of the proposed approach is assessed against numerical results generated in the current study and existing experimental results collected from the literature. The presented comparisons show that the CSM provides consistently more accurate member buckling resistance predictions than the current EN 1993-1-4 design rules for all stainless steel grades. The reliability of the proposed approach is demonstrated through statistical analyses performed in accordance with EN 1990. Finally, the paper presents a framework through which the proposed approach can be developed for other cross-section types and materials.The authors acknowledge the funding from MINECO (Spain) under Project BIA2016-75678-R, AEI/FEDER, UE “Comportamiento estructural de pórticos de acero inoxidable. Seguridad frente a acciones accidentales de sismo y fuego”. The first author would also like to acknowledge the financial support provided by the Spanish Ministerio de Educación, Cultura y Deporte through the José Castillejo-2018 scholarship.Peer ReviewedPostprint (author's final draft
Sustainable construction through reclaimed steel components: implementation and demonstration in the drastic EU project
No full textThe European building sector is a significant contributor to global greenhouse gas emissions, with embodied emissions in construction materials, particularly steel, playing a critical role. As European policies shift towards energy-efficient buildings, the focus on reducing embodied carbon has intensified. This paper examines the application of reclaimed steel components in new construction as a strategy to reduce embodied carbon, improve life-cycle performance, and support the circular economy. The study focuses on the development of a Demonstrator within the DRASTIC EU project, aimed at implementing innovative solutions for reducing both operational and embodied carbon emissions in steel construction by reusing steel from the Litoral de Almería Thermal Power Plant to construct a new warehouse in Balaguer (North-East of Spain). The paper outlines the process of reclaiming, inspecting, testing, and reusing steel components according to the latest European standards, emphasizing the role of traceability and advanced structural assessments. This initiative will highlight the potential of steel reuse in achieving significant sustainability goals in construction, offering a replicable model for future projects across Europe.This project has received funding from the European Union’s Horizon Europe research and innovation programme under Grant Agreement No. 101123330. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or Horizon Europe. Neither the European Union nor the granting authority can be held responsible for them.Postprint (published version
Sustainable construction through reclaimed steel components: implementation and demonstration in the drastic EU project
No full textThe European building sector is a significant contributor to global greenhouse gas emissions, with embodied emissions in construction materials, particularly steel, playing a critical role. As European policies shift towards energy-efficient buildings, the focus on reducing embodied carbon has intensified. This paper examines the application of reclaimed steel components in new construction as a strategy to reduce embodied carbon, improve life-cycle performance, and support the circular economy. The study focuses on the development of a Demonstrator within the DRASTIC EU project, aimed at implementing innovative solutions for reducing both operational and embodied carbon emissions in steel construction by reusing steel from the Litoral de Almería Thermal Power Plant to construct a new warehouse in Balaguer (North-East of Spain). The paper outlines the process of reclaiming, inspecting, testing, and reusing steel components according to the latest European standards, emphasizing the role of traceability and advanced structural assessments. This initiative will highlight the potential of steel reuse in achieving significant sustainability goals in construction, offering a replicable model for future projects across Europe.This project has received funding from the European Union’s Horizon Europe research and innovation programme under Grant Agreement No. 101123330. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or Horizon Europe. Neither the European Union nor the granting authority can be held responsible for them.Postprint (published version
Revolutionizing steel structures: bridging research and sustainable design for future societal impact
No full textThis paper delves into the transformative journey from advanced analysis in steel structures to establishing a design paradigm for the construction sector –responsible for 50% of raw material extraction, 40% of all energy consumption and 36% of greenhouse gas emissions–, aligned with the European Green Deal requirements. In this context, the utilization of novel design and assessment methods, empowered by the use of digital technologies, and the establishment of a comprehensive framework for the reuse of reclaimed steelwork represent the two main paths towards a reliable and environmentally responsible steel structural design. The paper explores and underscores the main challenges that the research community needs to address for improving the sustainability and circularity of the steel construction sector, and presents two specific research projects that will contribute to address such shortcomings: the implementation of a fully documented demonstrator to showcase the reuse process for decarbonization, and the development of a holistic Decisions Support System that integrates system-based advanced design methods, Structural Health Monitoring and Life Cycle Assessment. Ultimately, this paper aims to provide insights into multifaceted aspects of smart, sustainable steel structures, advocating for system-based approaches to reshape the future of structural engineering and to ensure a resilient and environmentally conscious built environment.The research published herein is part of the RE-STEEL Project, PID2022-140178OB-I00, funded by MCIN/AEI/10.13039/501100011033/FEDER, UE, and has received funding from the European Union’s Horizon Europe research and innovation programme under the DRASTIC project, Grant Agreement No. 101123330. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the Ministry of Science, Innovation and Universities of Spain, the European Union or Horizon Europe, none of which can be held responsible for them.Peer ReviewedPostprint (published version
