bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analytical design method for the improvement of steel structures stability
Authors: Bové Oriol , Casafont Miquel , Ferrer Miquel , López‐Almansa Francesc , Roure Francesc 
Published: September 2021

AbstractThis article presents a design method for the improvement of steel structures stability by modifying their structural elements parameters. The available parameters can be selected from a predefined list of stiffness and ultimate capacities for joints and steel members. The proposed procedure is based on determining the critical load factor (ratio between the critical and the demanding loads: αcr = Pcr / PEd) and analyzing its sensitivity with respect to the design parameters, by using its gradient vector and Hessian matrix. The methodology is well suited for structures where the second order effects are relevant. A simple two parameter example is presented, and the general procedure for finite element analysis is outlined.
Study of Second‐order Effects of Steel Posts Supporting Rockfall Flexible Barriers
Authors: He Jian‐Wei , Zhao Lei , Liu Yao‐Peng , Chan Siu‐Lai 
Published: September 2021

AbstractFlexible barrier systems have been widely used to resist falling rocks to protect railways, highways and residential buildings. As one of the important components of the system, steel posts are the supporting structures to maintain the system integrality and should not fail before the failure of other components. Under the impact of falling rocks, the ring net panels undergo large deflection causing high compression forces on the steel posts. To more accurately capture the structural behaviour of the steel posts, the nonlinear effects due to the initial imperfection of steel posts are considered. The performance of an individual steel post extracted from a full‐scale test is studied and the result reveals that the post would suffer global buckling about the minor axis with initial imperfection considered. Hence, the second‐order effects of steel posts should be incorporated in the global analysis of the flexible barrier system under rockfall impacts.
Buckling problems of patch loaded plates with and without stiffeners – analytical approach
Authors: Mijušković Olga , Žugić Ljiljana , Šćepanović Biljana , Ćorić Branislav 
Published: September 2021

AbstractGeneralized analytical approach, with exact stress solutions, to buckling problems of in‐plane loaded plate with and without stiffeners has been presented through the case of locally distributed direct stresses. Several mathematical models have been chosen to represent high webs of steel girders under the patch load. Initially, the basic model has been built to simulate a girder used in the experimental research where the external load is equilibrated by support reactions. The second, more complex model included shear stresses along vertical stiffeners with a task to equilibrate the external loads, simulating a single web segment between the stiffeners of a long girder. The upgrade of the second model by adding a longitudinal stiffener resulted in the third model. Considering the complexity of stress distributions within the plate under such a demanding load, an analytical model for these problems has not been presented earlier. For the first time the influence of flexural stiffeners' rigidity on the plate buckling has been analysed with the exact solutions for in‐plane stress distributions, for simply supported plate. Results confirm the high quality of the analytical solution for the first and the second model and speak in favour of this approach and its potential for further upgrading in the case of the third model.
Numerical investigations on built‐up cold‐formed steel beams for long spans
Authors: Ungureanu Viorel , Luka•ević Ivan , Both Ioan , Dubina Dan 
Published: September 2021

AbstractThe material saving obtained by using thin‐walled cold‐formed steel elements is well‐known for small structures as well as for common industrial structures. Additional to the truss type structures, another solution for obtaining light‐weight elements consist of connecting cold‐formed steel profiles as the flange to the corrugated steel sheets as the web. The resistance spot welding connecting technique is an advanced solution which offers reduced manpower and time for element production. These built‐up elements have shown their feasibility and high bearing capacity in previous studies. The present paper highlights additional characteristic responses of cold‐formed steel elements that extend in the response of built‐up corrugated web beams. The parameters considered in the numerical model include the span of the beam, the height of the beam, the thickness of the corrugated web plates, the thickness of the shear panel, the number of resistance spot welds and the orientation of the beam axis. By considering the real case configuration of industrial buildings, pitched roofs require the beams to have an inclination. The analyzed inclined beams exhibited increased capacity due to the redistribution of internal forces, growing the attractiveness of this solution.
On the use of systems for tests on stainless steel members and frames aimed at interoperability
Authors: Chacón Rolando , Puig‐Polo Càrol , Real Esther 
Published: September 2021

AbstractAn experimental development of systems for tests on stainless steel members and frames aimed at providing interoperability is presented. In the context of the project PINOX, tests on stainless steel members and frames have been conducted and provided with traditional measurement techniques. In addition, systems aimed at providing interoperable data to other platforms were added, namely: i) Measurement systems for developing low‐cost sensor‐to‐cloud applications as well as Digital Image Correlation, ii) Displacement measurement for developing virtual and augmented reality applications and iii) terrestrial laser scan (TLS) measurements for developing IFC models for design and analysis across BIM platforms. In the first case, the interest is related to developing interoperable, low‐cost, cloud‐based, open‐source tools in the context of structural engineering laboratories. In the second case, the interest is the use of virtual (VR) and augmented reality (AR) as alternative media when deploying tests on structural elements. The third case is explored for obtaining measurements and tracking initial imperfections on real structures, with great interest for in situ applications. Conclusions about educational, technological and practical potential of these applications are pointed out.
APK: a network to improve the interest in steel construction
Authors: Muzeau Jean‐Pierre , Silva Loïc Da 
Published: September 2021

AbstractAPK was launched in 1991. It is now 30 years old and it continues to produce and to disseminate pedagogical resources and to bring academics and professionals together. Every 4 years, seminars are proposed to examine how to adapt the different curricula to be as close as possible to professional requirements. Alternately, a workshop is organized to focus on a specific problem related to the advantages of steel in construction. Three times a year, a consistent journal which contains useful tools to improve lectures is circulated.This paper describes how it has been possible for APK to maintain its activities and to remain as attractive as it was at the beginning. It emphasizes its main results, on the one hand for the academic world and, on the other hand, for the steel construction professionals. It clarifies the French system of education. It is a reminder of the European programs which have been disseminated. It describes some specific tools provided to the academics. It highlights proposals to attract students and make them interested in steel construction. It suggests different ways of promoting education to steel and provides some ideas to remain attractive in the future.
Reusability of existing structural steel
Authors: Coelho Ana M. Girão , Pimentel Ricardo , Sansom Michael 
Published: September 2021

AbstractUsing reclaimed structural steel on a project is an effective strategy to cut the environmental impacts associated with the production of new steel. This practice cannot be generalised to all structural steel however, as not all components can be effectively or safely reused. This paper focuses on single‐storey buildings, which are particularly attractive for reclaiming and reusing structural steel. Functional reusability requirements are set out below, in particular, the requirements related to the adequacy and reliability assessment of the reclaimed steel, to ensure that (i) the reclaimed material satisfies the performance requirements, which are essential for the mechanical, physical, dimensional, and/or other relevant properties of steel materials to ensure their adequacy to be used in structural design to EN 1993, (ii) the salvaged material meets the quality requirements from nominal specifications to ensure their reliability to be used in the structural design to EN 1993, and (iii) structures made from reclaimed steel have continued integrity.
Strain measurements on rails of crane runway girders to predict accurate wheel loads
Authors: Zauchner Paul , Kettler Markus , Unterweger Harald 
Published: September 2021

AbstractIn existing crane runways, data on the actual wheel loads acting on the crane rail are often missing. Therefore, approximated wheel loads have often to be assumed for static calculations of the crane runway girder. Within this paper, a method is presented that allows to calculate the actual wheel loads based on strain measurements on the crane rail. The idea is to measure strains on the rail at certain pre‐defined locations, while the crane is passing and calculate the wheel load from the measured strains. The correlation between the strains in the rail and the wheel load is determined in a numerical finite element study and in laboratory tests.The numerical studies also comprise several different geometries of crane runway girders. The objective is to verify the influences of them on the calculated strains in the rail. The results of the numeric calculations show, that the strains in the rail generally depend on the stiffness of the crane runway girder. The thickness of the upper flange and the web as well were identified as the main parameters. This behavior is also verified in laboratory tests.For the contact between the rail and the crane runway girder, two different cases have been investigated. The first analysis refers to a hard contact under compression which allows separation under tension. This configuration corresponds to cases with steel wearing plates beneath the crane rails. The second case considers an elastomeric rail pad between the rail and the crane runway girder.
Sustainable Housing Provision: A Case for the Vertical Extension of Steel Framed Buildings
Authors: Gillott Charles , Densley‐Tingley Danielle , Davison Buick 
Published: September 2021

AbstractThe UK is experiencing unprecedented housing demand, with traditional provision in suburbanised clusters now known to have negative environmental, economic and social impacts. An alternative to this is residential densification through vertical extension; generating a more sustainable urban form whilst also serving to increase circularity of material flows within the construction industry and reduce whole‐life carbon and energy requirements. As a result of their relative abundance, inherent durability, and ease of adaptation, multi storey steel framed buildings are particularly pertinent in this context. It is also likely that sufficient reserve structural capacity exists within this typology; resulting from overdesign, the employment of simplified analytic design methods, and the limited number of section sizes available for use. The relative portion of reserve buckling capacity originating from these sources is assessed using a modified version of the effective length method to account for column continuity in multi‐storey steel frames. This reveals the consideration of column continuity to contribute an average of 1.23 kN/m2 of reserve buckling capacity across typical office buildings, with the amount resulting from section size limitations varying with design scenario.
Steel based retrofitting interventions for existing masonry walls: a comparative numerical investigation
Authors: Zizi Mattia , Vari Alessandro , Colajanni Piero , De Matteis Gianfranco 
Published: September 2021

AbstractMasonry buildings constitute a significant portion of the architectural heritage all over the world, also in regions affected by a high seismic hazard. Since this constructional material is characterized by lack of tensile strength, as well as small deformation capacity, masonry structures could result hugely damaged if shaken by seismic forces. In order to avoid collapses and reduce structural damage, innovative retrofitting interventions are necessary to improve the seismic behavior of masonry structures. In this context, steel‐based techniques could be considered among the most suitable solutions. In fact, by using such a high‐performant material, additional strength and ductility may be conferred to existing masonry structures. Based on these premises, the present paper focuses on a numerical investigation of two different retrofitting techniques: the CAM© system and the application of steel grids on both faces of a masonry wall. In particular, on the base of an experimental test carried out within the research project In.CAM.M.I.N.O. on an unreinforced masonry wall tested in condition of constant vertical force and horizontal loads, a reference FE Model has been calibrated in Abaqus by using a macro‐modelling approach with a damage‐plasticity material model for the masonry. Then, based on the reference model, the efficiency of the two systems has been investigated and compared by means of numerical analyses, in order to evaluate the strength and ductility increases obtainable by the application of the two retrofitting techniques.
Laser tube technology ‐ A new automation procedure in end‐preparation of CHS‐to‐CHS intersections welded by partial joint penetration (PJP): design, constructional and experimental remarks
Authors: Mastropasqua Augusto , Majowiecki Massimo , Duarte Claudio 
Published: September 2021

AbstractOver the past decade, the manufacturers of the most advanced laser‐cutting machinery have made significant breakthroughs in the CNC (computer numerical control) field, by utilizing the efficiency of the reversible laser‐beam (multi‐axis robotic system). In this paper, welded tubular connections for structural applications are studied with explicit reference to these new end‐machining possibilities. In particular, the case of circular hollow sections (CHS) is dealt with, whereby the class of connection typically referred to is known as CHS‐to‐CHS connections. Thanks to the Laser‐Tube‐Cutting technology (LTC), it is now possible, for Partial Joint Penetration (PJP) or Compound Joint Penetration (FW+PJP) to establish size, position and spatial inclination of the throat‐plane along the welded path, allowing the structural designers to better simulate the real stress distribution through the welded region (WR) and the nominal throat‐plane (TP) surface. The study is concluded with some interesting as‐built case studies and the results obtained from an LTC‐experimental phase aimed at obtaining 5 samples that are wholly compatible to the EN(ISO)9692, AS/NZS1554 and AWS‐D1.1 welding codes.
Effect of weld residual stress on fatigue strength
Authors: Manai Asma 
Published: September 2021

AbstractResidual stress (RS) refers to the stress permanently present in structures without any external load. This stress can be introduced by different sources, for instance, weld, post‐weld treatment, etc. Weld is a joining process that is associated with intensive heating which leads to considerable change in local material microstructure and the formation of high residual stresses in the welded joint. Residual stress introduces a change in the stress ratio, which means a change in the characteristic of cyclic loading which can have a detrimental effect on the fatigue strength of welded joints. In this paper, an experimental and numerical study of weld residual stress through the thickness direction at the weld toe of transversal attachment made with S355 was investigated. It was found that weld induced compressive residual stress at the surface. In the case where weld induces compressive residual stress, the fatigue life is 4.5 times higher than the standard as‐welded S‐N curve (when tensile residual stress is introduced)
The Effect of Steel Strength on the Behavior of a K‐Joint in a Slim‐floor Truss
Authors: Saremi Pooya , Lu Wei , Puttonen Jari , Pada Dan , Kesti Jyrki 
Published: September 2021

AbstractThis paper studies the applicability of the strain‐limit criterion in the Eurocode 3 to defining the limit load for a K‐type truss joint, which connects two tubular braces to a plate chord. The joint is used in a novel Finnish slim‐floor system with integrated load‐bearing members of High‐Strength Steel (HSS). The Finite‐Element Model (FEM) of the joint is validated by the experimental results of scaled‐down, isolated joint specimens made of S420 and S700 steel. The validated FEM is used to study the failure of the joint and the effect of steel strength on the failure mode. For the specific geometry of this joint, the criterion based on the 5% strain limit proposed by the Eurocode 3 was found to be well justified for the steel grades S235 and S355 and reasonably applicable to the steel grades S460 and S550. However, the results indicated that the value of 5% for the strain limit was too large, if the joint was made of the S690 steel grade.
Numerical analysis of the stress‐strain behaviour in statically determinate composite steel‐concrete beam after 100 years creep phenomena process using Volterra Integral Equations
Authors: Kazakov Konstantin , Stoyanov Chavdar , Partov Doncho , Kantchev Vesselin 
Published: September 2021

AbstractThe paper presents a precise analysis of the stress‐strain behaviour due to creep in statically determinate composite steel‐concrete beam according to numerical method in comparison with EM method of Dischinger. The analysis is based on the results obtained by numerical solution with Volterra integral equations, derived for determining the redistribution of stresses in beam section between concrete plate and steel beam with respect to time “t”. The creep law of concrete, according EC2 provisions is used. On the basis of the theory of the viscoelastic body of Arutyunian– Trost‐Bažant it is analyzed the migration of stresses from concrete plate to steel beam using two independent Volterra integral equations of the second kind. The duration of the course of study was adopted 100 years. Developed method will allow soon be confronted methods for calculating the composite beams according to EC4 considering rheology of concrete, based on the reduced elastic modulus of concrete.
Recent Advances in the Syntheses and Catalytic Applications of Homonuclear Ru‐, Rh‐, and Ir‐Complexes of CNHC^C Cyclometalated Ligands
Authors: Tiwari Chandra Shekhar , Illam Praseetha Mathoor , Donthireddy S. N. R. , Rit Arnab 
Published: September 2021

AbstractIn the past few decades, chemistry of cyclometalated species has gained momentum with increased applications in several areas of scientific developments. Cyclometalation reactions result in the formation of stable metallacycles through the generation of metal‐carbon covalent bonds by activating the unreactive Csp2‐H or Csp3‐H bonds. The extra stability gained by the formation of metallacycles enhances their applicability scopes especially in the area of homogeneous catalysis. In the recent research development in this area, NHC ligands (strong σ‐donor and generally, weak π‐acceptor) have been found to be one of the most suitable candidates for the intramolecular C−H activation process which leads to the cyclometalated species. The growth in the area of cyclometalation chemistry that started in the late 20th century is still continuing and in the past few decades, various examples of NHC derived transition metal‐based cyclometalated complexes came into the picture. As covering all the reported literatures in this area (includes mainly late transition metals) will exceed the limits of minireview, we restricted ourselves to the recent (2015 – May 2021) examples of the most common Ru‐, Rh‐, and Ir‐based CNHC^C cyclometalated complexes and their applications in various homogeneous catalytic conversions such as transfer hydrogenation, amidation, oxidation of alcohols, annulations, and so forth.
Direct Synthesis of Tri‐/Difluoromethyl Ketones from Carboxylic Acids by Cross‐Coupling with Acyloxyphosphonium Ions
Authors: Ispizua‐Rodriguez Xanath , Munoz Socrates B. , Krishnamurti Vinayak , Mathew Thomas , Prakash G. K. S. 
Published: September 2021

AbstractA simple and straightforward approach to the synthesis of trifluoromethyl and difluoromethyl ketones from widely available carboxylic acids is disclosed. The transformation utilizes an acyloxyphosphonium ion as the active electrophile, conveniently generated in situ from the carboxylic acid substrate by using commodity chemicals. The utility of the reaction system is exemplified by its chemoselectivity, with tolerance to a variety of important functional groups. The late‐stage functionalization of carboxylic acid active pharmaceutical ingredients and pharmaceutically relevant compounds is also discussed.
Single Amino‐Acid Based Self‐Assembled Biomaterials with Potent Antimicrobial Activity
Authors: Misra Souvik , Mukherjee Soumyajit , Ghosh Anamika , Singh Pijush , Mondal Sanjoy , Ray Debes , Bhattacharya Gourav , Ganguly Debabani , Ghosh Alok , Aswal V. K. , Mahapatra Ajit K. , Satpati Biswarup , Nanda Jayanta 
Published: September 2021

AbstractThe design and development of soft biomaterials based on amino acid and short‐peptide have gained much attention due to their potent biomedical applications. A slight alteration in the side‐chain of single amino acid in a peptide or protein sequence has a huge impact on the structure and function. Phenylalanine is one of the most studied amino acids, which contains an aromatic phenyl group connected through a flexible −CH2− unit. In this work, we have examined whether flexibility and aromatic functionality of phenylalanine (Phe) are important in gel formation of model gelator Fmoc‐Phe‐OH or not. To examine this hypothesis, we synthesized Fmoc‐derivatives of three analogues unnatural amino acids including cyclohexylalanine, phenylglycine, and homophenylalanine; which are slightly varied from Phe. Interestingly, all these three new analogues formed hydrogels in phosphate buffer at pH 7.0 having different gelation efficacy and kinetics. This study suggests that the presence of aromatic side‐chain and flexibility are not mandatory for the gelation of this model gelator. Newly synthesized unnatural amino acid derivatives have also exhibited promising antimicrobial activity towards gram‐positive bacteria by inhibiting cellular oxygen consumption. We further determined the biocompatibility of these amino acid derivatives by using a hemolysis assay on human blood cells. Overall studies described the development of single amino acid‐based new injectable biomaterials with improved antimicrobial activity by the slight alteration in the side‐chain of amino acid.