bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resistance prediction of laminates, fillet‐welded and full penetration‐welded bolted T‐stub connections
Authors: Aquino Giovani Jesus Berrospi , Alatrista Gustavo Alberto Neira , Miranda Walter Guillermo Loaiza , Aparcana Carlos Alberto Juárez , Miranda Jorge Hernán Alencastre , de Cisneros Fonfría Juan José Jiménez 
Published: September 2021

AbstractBolted end plate connections are usually considered an optimal alternative in rigid‐frame steel design because they have competitive costs and good structural behaviour. The characterization of this type of connection is defined by the moment‐curvature relationship in terms of strength, stiffness and ductility, and the method of components is the analytical procedure proposed by the Eurocode standard to predict the rotational behaviour. The T‐stub is the component that idealizes the transfer of tensile forces in components of the column flange and the endplate in bending components and is composed by one T‐shape element made of a web in tension joined to a flange in bending. The connection between the web and the flange can be set continuously (in rolled profiles) or welded, and the type of welding procedure considered, fillet or by full penetration, depends on the type of loads that the connection is submitted. e.g., in the case of dynamically loaded structures, in machinery supports or structures emplaced on seismic zones, is recommended the use of full penetration to avoid a premature failure by fatigue.This paper exposes the study results of the influence of the three types of connections between the web and the flange in T‐stub connections. Monotonic loading tests, applied by a universal test machine and analysed by the Digital Image Correlation technique, have been performed at laboratories of the Pontificia Universidad Católica del Perú. Results, represented by Force‐displacement characteristics curves and strains and stresses fields, are compared with the evaluation of analytical formulae, and the results of a FEM model developed to analyse the component. The conclusions are that the type of connections between the web and the flange greatly influences the T‐stub behaviour. Currently, the bibliography defines specific values for the variable m (defined as the equivalent distance from the centre of a fastener to the plastic hinge form near to the web face) for cases of laminated or fillet welded T‐stub connections. However, there is no prescription to analyse the structural behaviour of T‐stub welded by full penetration. We recommend a deeper study for this typology of connections to propose additional values in future versions of the Eurocodes.
Experimental study of various stiffened openings
Authors: DURIF Sébastien , BOUCHAIR Abdelhamid , AL‐DAFAFEA Taher 
Published: September 2021

AbstractOpenings in the web of steel beams have a growing use in steel and composite structures. However, in some cases, the presence of large web openings reduces significantly the beam strength, especially in areas of high shear or when a local force is being applied at the location of an opening. As a consequence, steel manufacturers often need to weld stiffeners to reinforce the openings. The actual European design rules do not provide design guidelines for those stiffeners. However, previous design codes, such as the ENV version of the Eurocode, propose some limitations. An example of limitation is to not consider the stiffener additional section in the bending strength of the opening member in the case of a single sided stiffening configuration. However, it could be observed that this kind of limitation can be very conservative. Thus, two experimental test campaigns have been led in order evaluate the behavior of openings with stiffeners. Different stiffening configurations have been tested and evaluated regarding the opening member deflection, strain distribution and strength. The first campaign consists of testing a beam with a rectangular opening in three points bending. Those tests allow the observation of the Vierendeel mechanism and its reinforcement provided by various stiffening configurations. The second test campaign is dedicated to the study of openings loaded directly on the upper member. Those tests allow the comparison of the mechanical behavior between various opening shapes and stiffening configurations under local load.
Numerical and analytical study of intermediate web‐post buckling
Authors: DURIF Sébastien , BOUCHAIR Abdelhamid , LOPES Nuno 
Published: September 2021

AbstractIn the case of two adjacent large web openings, the beam may fail by the plastification or the buckling of the intermediate web part known as the web‐post failure. Various analytical approaches have been developed to define the failure load of the intermediate web‐post which can be a key point in the design of beams with web openings. The authors led numerical studies on rectangular openings. Those studies allowed to observe that in a majority of cases, the web‐post reaches a total plastic strength. Furthermore, it allowed to observe that the loss of the web‐post did not lead to the beam failure. The beams generally failed by the formation of a Vierendeel mechanism of an enlarged or elongated opening. As a consequence, the authors propose an alternative approach for the definition of the web‐post buckling strength, considering the web‐post failure load based on lateral buckling failure and on the additional strength provided by the formation of a plastic mechanism.
Improvement of fatigue strength in heavy steel constructions through arc brazing
Authors: Gericke Andreas , Drebenstedt Karl , Kuhlmann Ulrike , Henkel Knuth‐Michael 
Published: September 2021

AbstractThe possibility of arc brazing of non‐loaded attachments with the filler material CuAl7 instead of welding on cyclically stressed steel constructions was investigated. The notch effect under cyclic loading was significantly reduced for non‐loaded arc brazed plates on base material of S355 and therefore the fatigue strength improved. The specimens did not show sensitivity to changes of the thickness and size of the non‐loaded arc brazed plates during fatigue testing. Furthermore, no negative thickness effect by increasing the thickness of the base material was observed. Microstructural analysis showed that the dimension of the heat affected zone was reduced through reduced heat input and that liquid metal penetration (LMP) occurs in the base metal, which has no negative effect on fatigue strength. Measurements of residual stresses in the weld / braze toe area showed that tensile residual stresses have not significantly been reduced, which can be attributed to comparable reactional forces of the copper alloy during cooling through a higher coefficient of thermal expansion. Numerical analysis showed that compared to a welded detail, the stress concentrations on the weld toe of the arc brazed fillets drop significantly due to the lower Young's Modulus of the alloy. The static testing of the load bearing capacity of arc brazed attachments showed that high tensile and shear stresses, which are comparable to the strength of the base metal, can be reached before fracture.
Material testing and analysis of WAAM stainless steel
Authors: Kyvelou Pinelopi , Slack Harry , Buchanan Craig , Wadee M. Ahmer , Gardner Leroy 
Published: September 2021

AbstractWire and arc additive manufacturing (WAAM) is a method of 3D printing that enables large structural elements to be built, with reasonable printing times and costs, making it well suited to applications in the construction industry. There is currently, however, limited information relating to the structural performance of WAAM material. Uncertainties include the basic mechanical properties, the degree of anisotropy and the influence of the as‐built geometry. Towards addressing this knowledge gap, a comprehensive series of tensile tests on coupons cut from WAAM stainless steel sheets was conducted and the results are presented and analysed herein. As‐built and machined coupons were tested to investigate the influence of the as‐built geometrical irregularity on the stress‐strain characteristics, while material anisotropy was explored by testing coupons produced at 0°, 45° and 90° to the printing layer orientation. Advanced non‐contact measurement techniques were employed to determine the geometric properties and deformation fields of the test specimens, while sophisticated analysis methods were used for post processing the resulting test data. The underlying material stress‐strain response, as determined from the tensile tests on the machined coupons, revealed a significant degree of anisotropy while the effective mechanical properties of the as‐built material were shown to be strongly dependent on the level of geometric variability arising from the printing process.
Characterisation of the anisotropic response of wire and arc additively manufactured stainless steel
Authors: Hadjipantelis Nicolas , Weber Ben , Gardner Leroy 
Published: September 2021

AbstractIn contrast to conventional structural steel and stainless steel, wire and arc additively manufactured (WAAM) material can exhibit a strongly anisotropic response. To investigate the degree of anisotropy in WAAM sheet material, data obtained from tensile tests on machined and as‐built stainless steel coupons are utilised. The WAAM material was tested in three different loading directions relative to the deposition direction and the response was captured using digital image correlation; a summary of the key results is presented. In the elastic range, the observed mechanical response is characterised using an orthotropic plane stress material model, which requires the definition of two Young's moduli, the Poisson's ratio and the shear modulus. Good agreement between the test results and the theoretical predictions based on the orthotropic material model is demonstrated. In the inelastic range, to describe the anisotropic yielding of the material, the well‐known Hill's criterion utilising the 0.2% proof stresses is employed. Overall, the elastic and inelastic properties of the studied material are shown to vary significantly with the direction of loading.
A Damage‐Controlled Behavior Factor (EC8) for Seismic Design of Steel Irregular Space MRFs
Authors: Tzimas Angelos S. , Skalomenos Konstantinos A. , Beskos Dimitri E. 
Published: September 2021

AbstractA main aspect to consider in seismic design of building structures according to EC8 is the selection of the behavior factor, q, which is directly related to the energy dissipation capacity of the structure. The prescribed values of q (1) are referred only to one limit state; (2) depend on the structural system and on the ductility class; (3) are constant; and (4) are not directly related to structural and non‐structural demands. Based on the literature, the inelastic seismic response of irregular building structures cannot be always estimated with safety by utilizing the methods of current seismic design codes. In this work, a preliminary performance‐based seismic design method which incorporates deformation‐controlled q factors, to better control the structural and non‐structural damage, is developed for space steel moment resisting frames irregular in plan view and in elevation within the framework of hybrid force/displacement (HFD) seismic design method. A large seismic response databank is generated on the basis of 88 space irregular MRFs, subjected to 42 pairs of ordinary ground motions, to develop the necessary empirical equations employed by the HFD. A realistic design example serves to demonstrate the advantages of the proposed method over the seismic design procedure of EC8.
Patch load resistance of longitudinally stiffened steel plate girders: A parametric study
Authors: Kovacevic Sasa , Ceranic Aleksandar , Markovic Nenad 
Published: September 2021

AbstractIn this paper, an in‐depth nonlinear finite element analysis is carried out on longitudinally unstiffened and stiffened welded I‐steel plate girders subjected to patch loading. The most realistic load case is during the incremental launching of multi‐span steel and composite bridges over temporary or permanent supports. Bridge plate girders are usually reinforced by longitudinal and transverse stiffeners in order to prevent web panel buckling and to increase the bending and shear strength. The current European design standard EN 1993‐1‐5 also requires a stability control check for concentrated transverse forces (patch loading) since it can be a decisive design criterion. By using longitudinal stiffeners for flexural and shear resistance, the patch loading carrying capacity can be increased as well. Previous experimental studies showed that the EN1993‐1‐5 patch loading resistance model significantly underestimates the ultimate strength of longitudinally stiffened plate girders. The paper is primarily dealing with numerical research of the post‐buckling behavior and ultimate strength of longitudinally stiffened I‐steel plate girders reinforced by one longitudinal stiffener. The main objective of the present work is to investigate the influence of different geometrical parameters, including patch load length, web panel aspect ratio, and initial geometrical imperfections, on the ultimate strength of longitudinally stiffened plate girders. We showed in this study that for all the considered initial geometrical imperfections, the patch load resistance increases as the patch load length is increased. The lowest ultimate strength of longitudinally stiffened plate girders was determined for initial geometrical imperfections that resembled the deformed shape at collapse (collapse‐affine imperfections). The web panel aspect ratio also influenced the patch load resistance and lower ultimate strengths were returned for bigger web panel aspect ratios. Finally, further research recommendations are presented.
Experimental investigations of the flexural‐torsional buckling resistance: Steel rolled I‐section beam‐columns under moment gradient
Authors: Gizejowski Marian A. , Kozlowski Aleksander , Stachura Zbigniew 
Published: September 2021

AbstractBeam‐columns of uniform rolled or equivalent welded sections are the member types most commonly used in steel skeletal structures. EN1993‐1‐1 [1] provides two design procedures of such members, one based on the interaction equations for the section resistance and the member buckling resistance, and the other one based on the so‐called General Method (GM) that tends to follow that of Ayrton‐Perry's procedure used for extreme cases of compression without bending and bending without compression. Above cited design procedures yield similar results when the beam‐column is predominantly under bending but sometimes results being away from each other when the beam‐column is predominantly under compression. Recently, a novel version of GM has been proposed [2], providing a tool of more rational design that yields the results from Eurocode 3 interaction equation procedure in both extreme cases. The proposed procedure is based on the Euclidean norm of dimensionless action effects and evaluation of Maquoi‐Rondal imperfection factor interpolated between those for compression without bending and bending without compression. This analytical procedure was verified with a wide range of advanced numerical simulations incorporating geometrical and material imperfections (residual stresses). In order to validate the accuracy of the proposed procedure, an experimental study on the buckling resistance of rolled I‐section beam‐columns was carried out the results of which are presented in this paper. Firstly, an overview of the experimental programme carried out on subframe specimens is given and then followed by the summary of measurements of deformations as well as global load vs. displacement characteristics for selected specimens. Finally, an assessment of the beam‐column buckling resistance, experimental vs. predicted by Eurocode 3 interaction equations procedure, is presented and conclusions with regard to the preliminary validation exercise are drawn.
Principles and Design Strategies for Ultra‐efficient Production Systems in the Process Industry
Authors: Schutzbach Maximilian , Full Johannes , Kiemel Steffen , Waltersmann Lara , Sielaff Lennard , Miehe Robert , Sauer Alexander 
Published: September 2021

AbstractA sustainable design of production systems, both within and beyond company boundaries, is essential for the future viability of the process industry. In this context, the concept of ultra‐efficiency has recently been developed, aiming at achieving holistic improvements in the fields of action energy and material efficiency, emission reduction, organization, human and staff, with the goal of establishing a positive impact factory. In this paper, the concept developed mainly for the discrete manufacturing industry is transferred to the process industry. It is put into the scientific sub context and elementary approaches, methods and strategies for factory planning and design of production processes in the process industry are summarized.
Management and outcome across the spectrum of high‐risk patients with myocardial infarction according to the thrmobolysis in myocardial infarction (TIMI) risk‐score for secondary prevention
Authors: Grinberg Tzlil , Bental Tamir , Hammer Yoav , Assali Abid , Vaknin‐Assa Hana , Wiessman Maya , Perl Leor , Kornowski Ran , Eisen Alon 
Published: September 2021

AbstractBackgroundPatients with myocardial infarction (MI) are at increased risk for recurrent cardiovascular events, yet some patients, such as the elderly and those with prior comorbidities, are particularly at the highest risk. Whether these patients benefit from contemporary management is not fully elucidated.MethodsIncluded were consecutive patients with MI who underwent percutaneous coronary intervention (PCI) in a large tertiary medical center. Patients were stratified according to the thrombolysis in myocardial infarction (TIMI) risk score for secondary prevention (TRS2°P) to high (TRS2°P = 3), very high (TRS2°P = 4), or extremely high‐risk (TRS2°P = 5–9). Excluded were low and intermediate‐risk patients (TRS2°P < 3). Outcomes included 30‐day/1‐year major adverse cardiac events (MACE) and 1‐year mortality. Temporal trends were examined in the early (2004–2010) and late (2011–2016) time‐periods.ResultsAmong 2053 patients, 50% were high‐risk, 30% very high‐risk and 20% extremely high‐risk. Extremely high‐risk patients were older (age 74 ± 10 year) and had significant comorbidities (chronic kidney disease 68%, prior CABG 40%, heart failure 78%, peripheral artery disease 29%). Drug‐eluting stents and potent antiplatelets were more commonly used over time in all risk‐strata. Over time, 30‐day MACE rates have decreased, mainly attributed to the very high (11.3% to 5.1%, p = .006) and extremely high‐risk groups (15.9% to 8.0%, p = .016), but not the high‐risk group, with similar quantitative results for 1‐year MACE. The rates of 1‐year mortality remained unchanged in either group.ConclusionWithin a particularly high‐risk cohort of MI patients who underwent PCI, the implementation of guideline‐recommended therapies has improved over time, with the highest‐risk groups demonstrating the greatest benefit in outcomes.
Inside the ESG ratings: (Dis)agreement and performance
Authors: Billio Monica , Costola Michele , Hristova Iva , Latino Carmelo , Pelizzon Loriana 
Published: September 2021

AbstractWe analyze the ESG rating criteria used by prominent agencies and show that there is a lack of a commonality in the definition of ESG (i) characteristics, (ii) attributes and (iii) standards in defining E, S and G components. We provide evidence that heterogeneity in rating criteria can lead agencies to have opposite opinions on the same evaluated companies and that agreement across those providers is substantially low. Those alternative definitions of ESG also affect sustainable investments leading to the identification of different investment universes and consequently to the creation of different benchmarks. This implies that in the asset management industry it is extremely difficult to measure the ability of a fund manager if financial performances are strongly conditioned by the chosen ESG benchmark. Finally, we find that the disagreement in the scores provided by the rating agencies disperses the effect of preferences of ESG investors on asset prices, to the point that even when there is agreement, it has no impact on financial performances.
Fabricating a Repairable, Recyclable, Imine‐based Dynamic Covalent Thermosetting Resin with Excellent Water Resistance by Introducing Dynamic Covalent Oxime Bonds
Authors: Li Guanglong , Zhang Xuhui , Yang Shuobing , Li Ting , Wang Yang , Chen Mingqing , Dong Weifu 
Published: September 2021

AbstractThe sustainable production of adaptive, recyclable and imine‐based dynamic covalent thermosetting resins (DCTRs) presents an opportunity for polymer scientists to address the prevalent environmental and energy concerns associated with current petroleum‐based plastics. However, the imine‐based DCTRs easily decompose in the presence of water, which can weaken the mechanical properties in imine‐based polymers. In this study, we designed oxime–imine DCTRs that are stable in the presence of water and exhibit good mechanical properties. In the presence of one kind of amino group catalyst, the oxime–imine DCTRs could be completely recycled. Additionally, these well‐designed oxime‐imine DCTRs have good mechanical properties, high glass transition temperatures (166 °C), and good thermal stabilities. Taken together, this work offers a sustainable solution for the design and manufacture of high‐value degradable materials intended for applications in which recyclability and reusability are indispensable.
SAR‐MARKOV: An energy efficient optimal routing method for WSN
Authors: Ram Garsukuti Mohan , Ilavarasan Egambaram 
Published: September 2021

SummaryIn most wireless sensor network (WSN) applications, energy efficiency is a major issue and also choosing an energy efficient routing is crucial for maximizing the network lifetime. In this paper, an energy efficient optimal routing method is presented for WSN based on SAR‐MARKOV model. Initially, nodes in the network are effectively clustered utilizing k‐means clustering in terms of energy, message size, and packet size to obtain the most reliable model of clustering. Afterwards, a Search and Rescue (SAR) optimization approach is utilized for optimal cluster head selection which works based on the SAR behavior of humans to optimize the constraints. After the selection of cluster head, the Markov model provides an accurate prediction of the shortest path to achieve energy efficient optimal routing. This work is implemented in NS2 platform. The experimental results of the presented approach provide improved performance than the different existing routing techniques in terms of throughput, packet loss ratio, packet delivery ratio, network lifetime, jitter, energy consumption, time complexity, end‐to‐end delay, and bit error rate.