bluuebunny/crossref_metadata_2025_split huggingface dataset:
Imperfection sensitivity study of hot‐rolled and laser‐welded stainless steel angle columns
Authors: Filipović Aljoša , Dobrić Jelena , Marković Zlatko , Baddoo Nancy 
Published: September 2021

AbstractStainless steel sections are used for structures in aggressive environments where the greater material cost can often be justified in return for longer maintenance‐free periods, for example in the water treatment, nuclear, petrochemical and food and beverage sectors. This paper presents a comparative imperfection sensitivity study of hot‐rolled and laser‐welded pin‐ended equal angle columns made of austenitic stainless steel grade 1.4301. Although the initial geometric imperfections in these structural elements are similar, there is a difference in the initial stress state due to the different manufacturing processes. The study includes three‐dimensional geometric imperfection measurements conducted by a laser scanner, and, in parallel residual stress measurements performed by the sectioning method using water jet cutting. The overall bow, camber, and twist imperfections are determined from the scanned specimens. In addition, the shapes of the residual stress patterns through the thickness of the angle leg are shown. Based on the findings related to imperfection distributions and amplitudes, a FE analysis is performed both on hot‐rolled and laser‐welded angles to study the influence of the variability of initial imperfections on compression resistance. The separate and combined effects of the measured residual stresses and initial out‐of‐straightness are considered and the reduction in the buckling resistances of initially straight angle columns is determined. The structural responses of hot‐rolled and laser‐welded columns are compared and discussed.
Shear Strengthening of Slender Steel Beams Using Cold‐formed Stiffeners and Adhesives
Authors: de Sousa Cardoso Hermano , Martins João Pedro , da Silva Luis Simões 
Published: September 2021

AbstractThis paper explores an alternative for strengthening shear‐deficient beams by fixing cold‐formed stiffeners with non‐welded joints at buckling‐prone regions. The usage of welds may not be suitable in slender beams as it introduces residual stresses and local distortion on the web. The cold‐formed stiffeners are disposed in diagonal orientation and its corrugate‐shaped geometry with high moment of inertia improves the out‐of‐plane stiffness of the beam web. The assessment of this method was performed in an experimental campaign which included three‐point bending tests of four beams. In two specimens, the cold‐formed stiffeners were fixed on the web by means of hybrid bonded‐bolted joints. Additionally, two control specimens were tested: a beam without diagonal stiffeners and a beam with diagonal welded‐steel plate.
Flexural buckling resistance of rectangular welded box section columns
Authors: Somodi Balázs , Kövesdi Balázs 
Published: September 2021

AbstractApplication of high strength steel (HSS – S420 and higher steel grades) is growing nowadays in the civil engineering praxis due to the numerous advantages compared to the normal strength steel (NSS – S235‐S355). The accurate consideration of the flexural buckling resistance of HSS structures is highly important in the design. Higher yield strength indicates the applicability of smaller cross‐sections, which might be more sensitive for stability problems. The purpose of the current study is (1) to investigate the flexural buckling behaviour of HSS welded rectangular box section columns and (2) to propose a reliable column buckling curve.Residual stress in steel structural elements have significant influence on the flexural buckling behaviour of welded box section columns. This phenomenon causes that hot‐rolled, cold‐formed and welded sections have different flexural buckling behaviour and resistance. Previous research results of the authors proved that different buckling curves can be used for HSS or NSS welded square box section columns. Research is continued and extended to the investigation of rectangular box sections, which significantly increase the applicability of the design proposals. The buckling resistances for NSS and HSS rectangular welded box section columns are determined by using deterministic numerical simulation technique for a wide range of relative slenderness and steel grades. Based on the simulation results buckling curves are proposed for all the analysed steel grades and aspect ratios.
Experimental study of welded austenitic stainless steel I‐section beam‐columns
Authors: Feber Nina , Jandera Michal , Rossi Barbara , Kremen Tomas 
Published: September 2021

AbstractStainless steel beam‐columns were experimentally and numerically investigated in this study. All members were subjected to compression and major axis bending induced by an eccentricity of the compressive load. The loading eccentricities for the tests varied to provide a wide range of bending moment‐to‐axial load ratios. The experimental program covers 10 welded I‐section specimens made of austenitic stainless steel grade EN 1.4301 (AISI 304L). Material tensile coupon tests and initial geometric imperfection measurements are also described in detail. Measurements of initial imperfections were performed using two different methods, using a mechanical dial and laser scanning. The test results were subsequently used for a validation of a finite element (FE) model, developed in ABAQUS software to replicate the beam‐column behavior. The accuracy of the models with the two combinations of local and global imperfections were evaluated by comparison with the test results.
Pseudo‐dynamic testing of a full‐scale two‐storey steel building with RBS connections
Authors: Di Benedetto Sabatino , Francavilla Antonella Bianca , Latour Massimo , Cavallaro Giovanni Ferrante , Piluso Vincenzo , Rizzano Gianvittorio 
Published: September 2021

AbstractAfter the earthquakes of Kobe (1995) and Northridge (1994) many research efforts have focused the attention on the seismic behaviour of partial strength beam‐to‐column joints because, in these seismic events, brittle fractures of welds of full‐strength joints belonging to MRFs have been observed. One of the most popular solutions developed in the aftermath to overcome the drawbacks of the typical welding joint details consisted in the adoption of the so‐called Reduced Beam Section (RBS) strategy. With this strategy beam ends are weakened into areas located sufficiently far from the column in order to reduce the stress concentration in the welds. Nevertheless, while many experimental efforts have been devoted to this connection typology, the available experimental results on full‐scale structures are still quite limited.Within this framework, aiming to provide a contribution to fill this knowledge gap, an experimental program concerning the pseudo‐dynamic testing of a full‐scale two‐storey steel building equipped with five different connection typologies is currently undergoing at the University of Salerno. In this paper the results of the first experimental campaign, dealing with MRFs with RBS connections, are presented. The mock‐up has been subjected to a sequence of seven accelerograms and the results have confirmed that, if properly designed, RBS connections provide large energy dissipation capacity and plastic rotation supply. Nevertheless, the failure of welds due to damage accumulation can be still possible, even adopting full penetration butt joint welding details conforming to Eurocode 3 and Eurocode 8 provisions.The experimental results have been complemented with numerical analyses developed with the software SeismoStruct. The comparisons between the numerical simulations and the experimental results show that the applied mixed distributed and concentrated plasticity approach, based on the adoption of phenomenological spring models, can capture accurately the global response of the structure, but it predicts with lower accuracy the local response parameters.
Weight optimization of stainless‐steel built‐up structural elements
Authors: Venslavavičiūtė Raminta , Daniūnas Alfonsas 
Published: September 2021

AbstractThis paper describes the use of stainless‐steel as a structural material, discusses current structural design considerations, reviews recent research work, and highlights important findings and developments.Over the past 25 years, structural design codes for stainless‐steel have been introduced or substantially altered or are still being modified, while at the same time there is a growing interest in the use of stainless‐steel in construction. Realistic modeling of structural elements of stainless‐steel plays an important role in the analysis and design of steel framed structures. Structural element modeling and optimization using stainless‐steel, in case a built‐up column, can contribute to existing research on stainless‐steel. The object under consideration is a stainless‐steel built‐up column, which is classified as atypical structural elements. The purpose of this optimization problem is to perform the minimization of the weight of the selected built‐up column, when the height of the column and the load acting on it are known. The built‐up column is considered with two different types of cross‐sectional chords: at first with circular (CHS) cross‐sectional chords and then with elliptical (EHS) cross‐sectional chords.A genetic algorithm based optimum design is presented for such a built‐up column. The design algorithm obtains a built‐up column with the least weight by selecting appropriate sections from standard set of duplex stainless‐steel hollow elliptical cross‐sections. The optimization model accounts for the strength and stability constraints. The built‐up column is under action of compressive axial force, bending moment and combination compressive axial force and bending moment. The parameters under consideration include the height and width of the outer cross‐section of the column's chords, the ratio of the outer cross‐sectional dimensions to the thickness and the initial eccentricity of the load. The computation results showed that the chosen optimization model and genetic algorithm allow efficiently obtaining the column of minimum weight, where the variables are column chord cross‐section and diagonals cross‐section. The design algorithm used to solve the problem is described in detail in this work.Until today, there is known that the lack of information prevented the recommended methodology from being properly established. Because of this, the obtained results confirmed that these types of structural elements of the steel in question are needed to develop a more efficient design of stainless‐steel structures in the design method and thus contribute to its wider use in construction.
Examination of Structural System of Hales Turgus Vilnius Shopping Center, Constructed with Iron and Steel in 1906
Authors: Aktuglu Yesim Kamile 
Published: September 2021

AbstractHales Turgus, Vilnius Shopping Hall, was built in 1906, in construction with iron‐and‐steel. It has a very special structure, constructed with iron‐and‐steel, inside the building. It has a perimeter wall, built with brick. All these main details are similar with the structural details of Budapest Central Market Hall (Nagy Vasarcsarnok), built in 1897 and also of Central Sofia Market Hall (Tsentralni Hali), built in 1909. All of these landmarks are having the similar architectural plan and similar iron‐and‐steel construction solution. And also the architectural planning of all three shopping halls will be examined, by comparing altogether. The connection of the structural system with the architectural planning will be defined to lead the way about how a new shopping hall, constructed with structural steel, can be designed in future. The reasons why they all are still in servive with their original function will be given through the meeting of architecture and structure of the building. In the paper, all these main similarities will be examined, through the structural details of iron‐and‐steel construction, through their sustainability features, which keep them still in service with their original function.
A Simplified Approach for Seismic Performances Estimation for Steel Moment Resisting Frames
Authors: Nastri Elide , Montuori Rosario , Piluso Vincenzo , Todisco Paolo 
Published: September 2021

AbstractSeismic events in recent years have underlined the need to quickly classify the built heritage in terms of seismic performances. The capacity of a structure can be assessed by means of inelastic analyses, requiring sophisticated numerical procedures. The simplified method herein proposed only requires use of common analyses such as the elastic structural analysis and the rigid‐plastic analysis. For this reason, it lends itself well to be used in the immediate aftermath of an earthquake, not requiring any static or dynamic non‐linear analyses. The proposed methodology has been set up by means of a large parametric analysis, carried out on 420 frames designed according to 3 different approaches: the first one is the Theory of Plastic Mechanism Control (TPMC), ensuring the design of structures showing global collapse mechanism (GMRFs), the second one is based on the Eurocode 8 design requirements (SMRFs) while the third is a non‐seismic design, based on design for vertical loads (OMRFs).
Structural performance evaluation of square hollow section column under compressive axial force with bending moment having different width‐thickness ratio
Authors: Hayashi Takuro , Sato Atsushi , Yoshioka Shimpei 
Published: September 2021

AbstractThe square hollow section (SHS) is commonly used for the column of the steel building structures in Japan. The moment‐resisting frame will resist the lateral force with the flexural manner of the columns. Under the seismic event, the bending moment will be significant, and the plastic hinge may be formed in the columns. It is crucial to understand the structural behavior at the component level to capture the structure system's ultimate limit state by computational simulation. Understanding the strength and the ductility is one of the essential aspects, but it is also crucial to know the structural elasto‐plastic behavior until the ultimate limit state. It is worthwhile to conduct the testing of the members under combined loading conditions. In this paper, the test results obtained from the different width‐thickness ratio SHS were reported. The forces subjected to the specimen were axial force and cyclic bending moment; therefore, the member was under combined loading condition. Collapse mode, maximum bending moment, and plastic deformation capacity were evaluated in consideration of the effect of the width‐thickness ratio; comparison study between the current design recommendation was also shown.
Steel Structure Prediction Model for Fixed Roof Oil Tanks
Authors: Denic Uros , Spremic Milan 
Published: September 2021

AbstractThis paper will focus on fixed roof storage tanks and its sub‐category cone roof tanks. Paper presents major factors and outputs of tank design process. Theoretical analysis is done for a cone roof tank model and correlation between tank surface, shell thickness and total steel weight used. Detailed algorithm for tank design was realized using MathCAD software using Eurocode standards. Using this algorithm, 432 hypothetical tanks were designed. Data analysis of the collected output data was analysed using R statistics programming language. Using regression models and testing them led to the optimum statistical model.For the purpose of this work, data for 21 real world tanks including fixed roof and floating roof tanks were collected. The data was collected with help of MOL, INA and few other EPC contractors. Paper compares real world data with outputs of the model.Model can be used for quick estimates and control of material consumptions. Taking few input parameters and applying minimal effort can lead to a very accurate steel consumption prediction. With additional real‐world data, acceptable ranges of deviation from the mean could be set‐up. Thus, allowing for better control on Client part or EPC companies.
Design and Construction of the Lille Langebro, Copenhagen
Authors: Fryer Simon , Eckhart Thomas , Nugent Peter 
Published: September 2021

AbstractThe Lille Langebro is the latest movable bridge to be built across the harbour in Copenhagen. Its design was the subject of an international competition commissioned in 2014 by the client, Realdania, and won by a collaboration of Buro Happold, Wilkinson Eyre and Eadon Consulting. The bridge has an overall length of 160m and carries pedestrians and cyclists over a 7m wide deck. The superstructure is steel comprising main longitudinal members that are triangular in cross section along each edge. The geometry is complex with plan curvature and an undulating profile, resulting in an interesting form that results in double curvature of the steel plates.The bridge has two sections that swing to allow shipping through a 35m wide navigation channel. In order to maintain a slender profile in elevation, an innovative moment connection has been designed to connect the moving parts together at midspan. This connection clamps the sections together but is released to allow longitudinal movements arising from temperature.The four bridge sections were entirely prefabricated, being assembled upside down in the workshop and then turned over. They were then delivered to site by sea for erection on site using a large capacity shear leg crane.
Ultimate Strength of K‐joints in Lattice Structures Composed of Circular Hollow Sections (CHS)
Authors: Đuričić Đorđe , Marković Zlatko , Janković Milena , Lučić Duško 
Published: September 2021

AbstractThis paper deals with the analysis of the design resistance of joints in lattice structures composed of welded circular hollow sections (CHS). The analysis was carried out on a K‐joint. Determination of the design resistance of lattice structures is based on the calculation of design resistance of compression members in uniform compression, taking buckling into account, in accordance with EN1993‐1‐1 and the calculation of design resistance of joints in lattice structures in accordance with EN1993‐1‐8.The value of the design resistance of compression members in uniform compression is obtained through new diagrams for the resistance of members used for determining the value of compression members' design buckling resistance for a given buckling length of a member.Calculation of resistance of brace members in K‐joints of a welded lattice structure composed of circular hollow sections (CHS) in accordance with EN1993‐1‐8 is analysed both according to the equations given in the adopted standard and according to the equations given in the new proposal for EN 1993‐1‐8.Through a comparative analysis of these two criteria, using appropriate diagrams, a simple procedure was given in order to calculate and determine whether the ultimate strength of the brace member was achieved by its buckling or by plastification of the chord member of the joint. The suggested diagrams give an evaluation of the utilization ratios of the adopted members of lattice structures. Provided the sections were properly chosen, it is possible to rationalize the structure.
Fire design proposal for members with cold‐formed lipped channel and sigma sections under compression
Authors: Arrais Flávio , Lopes Nuno , Real Paulo Vila 
Published: September 2021

AbstractSteel structural elements with cold‐formed thin‐walled sections are becoming increasingly common in buildings due to their lightness and ability to support large spans. In these members, local, distortional and global instabilities are important common failure modes. At high temperatures, these instability phenomena are intensified. This paper presents a numerical study on the behaviour of columns with lipped channel and sigma sections in case of fire when subjected to compression. A parametric study, considering different steel grades, temperatures and different cross‐sections with different slendernesses, is presented. Comparisons are also made between the numerical results and analytical design rules, such as the Part 1‐2 of Eurocode 3, using its Annex E or its French National Annex, where a different constitutive law is recommended for cold‐formed profiles. It is possible to conclude that the simple calculation rules are on the safe side but sometimes too conservative. Therefore, new proposals with adjustments to the current design rules are presented for these particular cases that are very common in cold‐formed steel constructions, in order to keep the results on the safe side becoming the design rules less conservative.
Construction of CoS2/Zn0.5Cd0.5S S‐Scheme Heterojunction for Enhancing H2 Evolution Activity Under Visible Light
Authors: Ma Lijun , Xu Jing , Zhao Sheng , Li Lingjiao , Liu Ye 
Published: August 2021

AbstractIn the field of photocatalysis, building a heterojunction is an effective way to promote electron transfer and enhance the reducibility of electrons. Herein, the S‐scheme heterojunction photocatalyst (CoS2/Zn0.5Cd0.5S) of CoS2 nanospheres modified Zn0.5Cd0.5S solid solution was synthesized and studied. The H2 evolution rate of the composite catalyst reached 25.15 mmol g−1 h−1, which was 3.26 times that of single Zn0.5Cd0.5S, whereas pure CoS2 showed almost no hydrogen production activity. Moreover, CoS2/Zn0.5Cd0.5S had excellent stability and the hydrogen production rate after six cycles of experiments only dropped by 6.19 %. In addition, photoluminescence spectroscopy and photoelectrochemical experiments had effectively proved that the photogenerated carrier transfer rate of CoS2/Zn0.5Cd0.5S was better than CoS2 or Zn0.5Cd0.5S single catalyst. In this study, the synthesized CoS2 and Zn0.5Cd0.5S were both n‐type semiconductors. After close contact, they followed an S‐scheme heterojunction electron transfer mechanism, which not only promoted the separation of their respective holes and electrons, but also retained a stronger reduction potential, thus promoting the reduction of H+ protons in photocatalytic experiments. In short, this work provided a new basis for the construction of S‐scheme heterojunction in addition to being used for photocatalytic hydrogen production.
Deciphering the Origin and Formation of Aminopyrrole Moiety in Kosinostatin Biosynthesis
Authors: Hu Yu , Zhou Qiang , Zhang Zhuan , Pan Hai‐Xue , Ilina Yulia , Metsä‐Ketelä Mikko , Igarashi Yasuhiro , Tang Gong‐Li 
Published: September 2021

Main observation and conclusionKosinostatin (KST) contains an uncommon aminopyrrole moiety, whose biosynthesis has remained elusive. Herein, aminopyrrolinic acid, which was generated by an L‐ectoine synthase‐like enzyme KstB3 via cyclization of L‐glutamine, was identified to be the real substrate of adenylation enzyme KstB1. Subsequently, a FAD‐dependent dehydrogenase KstB4 along with a transglutaminase‐like enzyme KstB6 were also involved in formation of aminopyrrole. These results provided an unusual pathway for 2‐aminopyrrole formation in KST biosynthesis.