bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proposal for the suitable choice of material to avoid brittle fracture on Jacket foundations
Authors: Krahl Philipp , Kühn Bertram 
Published: September 2023

AbstractIn the past years offshore wind turbines have been established as a source of renewable energies. Especially installations at greater distances from the shore and thus at increasing sea depths offer great potential. The foundations of these structures are exposed to complex load configurations while simultaneously exhibiting difficult environmental conditions. Although, there are currently no harmonized regulations with regard to the suitable choice of material to avoid brittle fracture for the hollow section joint structure of a Jacket foundation. In accordance with EN 1993‐1‐10 appropriate rules are given in terms of onshore structural engineering. Although, due to the differing conditions, these rules can not be applied to offshore foundations without further modifications. To achieve a suitable application, investigations regarding the material toughness requirements for Jacket foundations of offshore wind turbines were carried out. A parametric study regarding stress concentration was conducted to identify a reference geometry. Afterwards a fracture mechanics approach was applied to define the material toughness requirements. The obtained results served as a basis upon which a proposal to avoid brittle fracture for Jacket foundations was drafted.
Cyclic behavior of single and double‐angle bracing members employed in pipeline‐supporting structures
Authors: Go Hyun , Kim Hyung‐Joon 
Published: September 2023

AbstractConcentrically braced frames (CBFs) are widely used as the main lateral force‐resisting system in pipeline supporting structures. Their seismic performance mainly depends on the hysteretic response of bracing members. Axial members with single‐ or double‐angle sections have been commonly implemented although there is limited information on their cyclic behavior experimentally verified. This study prepares single‐ and double‐angle brace specimens with various width‐thickness ratios and slenderness ratios, performs cyclic loading tests. and compares their cyclic behavior obtained from the tests and back‐bone curves provided in standard.
Four‐point bending test of composite beam with Concrete‐GFRP cross‐section
Authors: Weissova Michala , Kvocak Vincent , Dubecky Daniel , Vanova Patricia 
Published: September 2023

AbstractThe objective of this study is to explore the application of polymer‐based materials in composite bridges. The paper incorporates both theoretical and practical insights from the field of composite bridges, with a specific focus on shear connectors. The primary aim of this research is to substitute steel with polymer‐based materials in the composite cross‐section. The paper will primarily concentrate on the experimental aspect of the study, employing mechanical analysis through a four‐point bending test. The outcomes of the experiment will encompass the maximum deformation and strength of the composite beam. Such results serve as an impetus for further research and establish the theoretical foundation for designing composite bridges utilizing more environmentally friendly, lightweight, and sustainable materials.
Bulb versus Trough
Authors: Hesselink Bert , Klamer Ernst , Vollema Nynke , Hiddingh Jan , Wijnbeld Bas 
Published: September 2023

AbstractWith the increasing traffic intensity and traffic loads, it can be questioned whether the application of orthotropic steel decks with troughs as longitudinal stiffeners is still the best solution. Possibly, the use of bulb profiles as longitudinal stiffeners could offer a better solution. Bulb profiles were commonly used till the late sixties but are no longer applied due to high manufacturing costs. However, new welding techniques have become available nowadays, which could possibly eliminate this disadvantage. In this study, a comparison is made between an orthotropic deck with troughs and with bulb profiles. For both deck types, an optimized design is made with respect to fatigue, after which both designs are compared with respect to weight, costs, production, maintenance, and inspection. Surprising outcome is that the bulb deck can be more favorable on certain aspects compared to the more recent trough deck.
3D‐printing with steel on thin sheets for application in free form façade construction: welding process development and material properties
Authors: Grebner Philipp , Lange Jörg 
Published: September 2023

AbstractWire and Arc Additive Manufacturing (WAAM) became a significant research field in structural engineering over the past years. It offers the opportunity to apply material fast and precisely, following the load path, inducing effective material consumption. Considering free‐formed sheet‐metal façades, to date large thicknesses are necessary to maintain the final shape and load‐bearing capacity that however causes high material consumption and costs during the construction processes. Hence, WAAM could be an opportunity to reduce the amount of mild steel used for free‐form façades. As part of a research project at TU Darmstadt, 1 mm thick free‐form sheet‐metal façades elements have been manufactured using WAAM. Due to precisely welded lattice structures, placed on the backside of the metal sheet, the reinforcement will be ensured. Wide studies on welding parameters focused on a stable process without damaging the later frontside of the façade panel and on process optimization. In addition, material properties of the welding material have been determined to check its usability in façade construction.
Gerda Taro Bridge ‐ a semi integral composite bridge
Authors: Boeters Ton , Cornelissen Lieuwe , Hesselink Bert 
Published: September 2023

AbstractFor the area developments on IJburg in Amsterdam, there was a need to connect the various islands with the mainland. The connection between the ‘Centrumeiland’ and the ‘Strandeiland’ is the Gerda Taro Bridge; with ‘Bridge 2125’ as project name. The Gerda Taro Bridge is part of the bridge family ‘Buitenwater’. The bridge is suitable for all types of road traffic and has a total length of approximately 115m.Royal HaskoningDHV did the complete engineering of the road bridge for both the tender phase and all design phases up to and including implementation in collaboration with contractor Ballast Nedam.The Gerda Taro Bridge consists of a steel‐concrete supporting structure. Both the main girders and cross girders consist of welded I‐sections. The concrete deck is connected by means of studs, ensuring composite action between the steel and the concrete. The deck structure is supported by spatially oriented steel hollow sections on five intermediate supports.
Influence of Imperfections in the Design of Crane Runway I‐Beams
Authors: Kováč Michal , Ároch Rudolf 
Published: September 2023

AbstractCrane runway beams are generally loaded by vertical and horizontal forces as well as not‐negligible torsional actions. Horizontal and torsional deformations originate already from the 1st order analysis. The effects of imperfections of crane runway beams could, at least partially, be simulated by these deformations. While for the purely vertically loaded beams it is necessary to consider the horizontal bow imperfection, for the generally loaded beams with horizontal forces as well, the influence of horizontal bow imperfection may not be as important, due to the occurrence of horizontal deflection from primary actions. Eurocode EN 1993‐6 allows to consider either eccentricities of vertical forces or introduction of horizontal bow imperfections in the design of crane runway beams. In this article, using a self‐developed FEM‐program, the effect of horizontal bow imperfection for the generally loaded crane runway beams is investigated. The two options of EN 1993‐6 are compared in the FEM analyses with the simplified design methods like the Annex A method of the same standard and the Naumes method.
Measurement and statistical analysis of deviations in the cross‐sectional geometry of hot‐rolled I‐sections
Authors: Steinmetz Robin , Taras Andreas 
Published: September 2023

AbstractIn the second generation of EN 1993‐1‐1, the variation in geometric and mechanical properties of European steel products are now statistically described in a dedicated “Annex E”. The partial safety factors γM for the resistance functions (design equations for strength) were calibrated based on these assumptions. However, while most past research has focused strongly on the mechanical properties and thus the corresponding scatter quantities are well known, there are still a few open aspects regarding the cross‐sectional dimensions. Due to this background and as an independent confirmation of the EN‐values with most recent data, in the present study a detailed measurement campaign on hot‐rolled I‐sections was carried out directly at depots of steel merchants in Switzerland. A total of 561 cross‐sections were measured and analysed. The results helped corroborate the characterisation in Annex E.
Influence of Temperature on the Behavior of Sandwich Panels
Authors: Steineck Sonja , Lange Jörg 
Published: September 2023

AbstractSandwich panels in the construction industry are used as roof and facade elements and usually consist of two thin face layers of steel and a thicker core of polyurethane (PU) or mineral wool in between. The PU core material is constantly being further developed. In addition to improvements in the physical properties, this further development also leads to changes in the mechanical properties. As a result, the design rules that were established for older foam systems must be reviewed at regular intervals. There is a great need for research into the temperature‐dependent behavior of the foam system. As these elements are used as roof and facade elements, they are directly exposed to climatic conditions. High temperatures are generated on the cover sheets due to solar radiation. The PU rigid foam changes its mechanical properties in this temperature range. Tests on small parts and components show a change in the stiffnesses and strengths, as well as the load‐bearing behavior under elevated temperature. Consideration of the temperature in the design is therefore of great importance. In view of the continuous further development of the foam system, statements regarding the core material from older research must be reconsidered.
Stress increases in crane runway girders due to rail joints
Authors: Kettler Markus , Unterweger Harald 
Published: September 2023

AbstractVertically acting wheel loads from overhead bridge cranes and potential additional horizontal crane loads induce two types of stresses in crane runway girders: i) global stresses due to bi‐axial bending and torsion and ii) local stresses which mainly affect the girder's web. The latter typically represent one of the most decisive criteria for the fatigue design check of welded girders and are the focus of this paper. Crane rails with foot flange are typically connected to the top flange with rail clips. These clips maintain the position of the rail in vertical and horizontal transverse direction, but they generally allow for longitudinal movement of the rail. Rails with foot flange are used with and without elastomeric bearing pads between the rail and the top flange of the girder. The local stresses in the webs of crane runway girders are strongly affected by discontinuities of the crane rails. Such discontinuities can originate from unplanned rail cracks as well as planned rail expansion joints. The current mechanical models for concentric as well as eccentric wheel loading in relevant design standards assume continuous crane rails. However, rail joints are expected to significantly increase the local stresses in the region beneath rail joints. The present paper focuses on the impact of rail joints on the local stresses in crane runway girders. The research activities comprise experimental tests as well as finite element calculations. The aim of the investigations is to develop a better understanding of the mechanical behaviour in order to avoid future fatigue damage due to an unexpected increase of local stresses at a rail joint.
Swift‐Constructed Demountable Blind Bolt for Fast Execution and Disassembling of SHS Connection
Authors: Han Xiao‐Zhou , Chan Tak‐Ming 
Published: September 2023

AbstractIn the past decades, blind bolts were developed for structural hollow section (SHS) connection, and various types of blind bolt products have been commercially available. Nevertheless, some of the existing blind bolts cannot be easily demounted without the need of machine cutting after installation. Even if some blind bolts can achieve demountable function for structure by leaving some components inside the tube during the removal process, their installation and removal speed probably require to be raised further, or their mechanical performances may need to improve further for wider application. Therefore, it is worthy to develop a demountable blind bolt that has better mechanical performance, as well as can be installed and demounted easily and fast. In this study, the swift‐constructed demountable blind bolt is proposed. Design details, installation and removal process, material selection, heat treatment selection, relevant material examinations, and fabrication method are introduced accordingly. Experimental investigation is conducted to validate the proposed objective of this proposed bolt. Test results reveal that this proposed bolt has satisfactory mechanical performance, and the improvement of bolt tensile strength compared with the existing product can be achieved appropriately.
Comparison between numerical models for unbraced multiple bay pallet racks
Authors: Bové Oriol , Casafont Miquel , Bonada Jordi , López‐Almansa Francesc 
Published: September 2023

AbstractUnbraced pallet racks are cold‐formed steel structures intended for the storage of products. They are subjected to severe lateral actions, and are particularly instability prone in the down aisle direction. Therefore, their design is compromised and needs of an accurate modelling. In current design practice, models using simplified beam formulations are regularly considered (such as Euler‐Bernoulli or Timoshenko), being them not able to reproduce torsional warping, or cross‐sectional distortion; these phenomena are accounted for indirectly via reduced sectional properties, and in the post‐process. This paper presents a comparison between three single column models, intended for the modelling of racks with a significant number of bays. Three models are presented: –Two 2D beam models using gross and equivalent section properties –A 3D beam model using equivalent section properties. Additionally, the results of these analyses are compared with those of a 3D model using shells and beams, presented in a previous research paper. Two rack configurations with different level heights are considered. The aim of this study is to capture the influence perforations of the uprights, warping, eccentricities and cross‐sectional distortion in the nonlinear response of racks subject to severe lateral actions.
Reliability Assessment of Eurocode 3 Design Rules for the Minor‐Axis Buckling of HSS I‐section Columns
Authors: Filho José Osvaldo Ferreira , da Silva Luís Simões , Tankova Trayana , Carvalho Hermes 
Published: September 2023

AbstractSince the main purpose of the codes is to provide satisfactory safety levels, the reassessment of the reliability of the current design rules considering the new structural steels, as high strength steels (HSS), is necessary. As the reliability directly depends on several variables, their influence should also be considered. This paper aims to evaluate the influence of the randomness of the geometry, material, initial geometrical imperfections and residual stresses on the minor‐axis flexural buckling resistance of S690 HSS welded I‐section columns and the reliability of the Eurocode 3 [1,2] stability design rules. Monte Carlo simulations were executed to obtain the ultimate resistance of simply‐supported compressive members with slenderness varying from 0.3 to 2.2. The basic variables were stochastically modeled using existing statistical distributions from the literature and each generated element was numerically analyzed by a general‐purpose finite element software. Finally, the influence of the randomness of the basic variables and the safety provided by FprEN1993‐1‐1 [2] is discussed.
Proposal for the approach of torsional restraint by sandwich panels under uplifting loads
Authors: Krieglstein Tim , Kühn Bertram , Naujoks Bernd 
Published: September 2023

AbstractSandwich panels are able to support their substructure against failure resulting from stability loss. Especially for the thin‐walled cross‐sections, practical spans can often only be realized by taking the stabilization into account. In mechanics, this stabilization can be described as a combination of shear field and torsional restraint. However, for the load combination of self‐weight and wind suction, the shear field is usually applied to the flange in tension, which means that only slight stabilization effects can be added to the system. In addition, there is no standardisation for the approach of a torsional restraint under uplifting loads. Recent investigations showed on the one hand that the reduction of the torsional restraint under uplifting loads given in the literature is correct, but on the other hand, they offer a specific quantification of the reduction. Thus, a qualified estimation of the applicable torsional restraint under uplifting loads, based on tests and calculations using the finite element method, is made possible on the basis of a well‐founded mechanical model. The scientific background to this as well as the mechanical model and a proposal for its application in construction practice are described below.
Simplified approaches for material characterization – an alternative for advanced fatigue design methods
Authors: Rauch Marion 
Published: September 2023

AbstractIntegral parts of the Sustainable Development Goals of the United Nations are to ensure a sustainable and robust infrastructure as well as affordable and clean energy. To satisfy these societal needs, wind energy plays a considerable role and an overall functionality of wind turbines is essential. Taking into account the current age of the installed onshore wind turbines in Germany, elongated service life and economic further operation are indispensable. The application of local concepts, such as the Two Stage Model, enables elongated service life by a detailed consideration of structural and fracture mechanics input parameters. For these advanced assessment methods, amongst others, material characterization is needed for a more accurate lifetime prediction. The required cyclic material properties are usually derived by time‐consuming incremental step tests. In this paper, simplified approaches for the cyclic material characterization, such as the easy‐to‐use Hardness Method, are presented as an alternative. The applicability of the Hardness Method is demonstrated by a proof‐of‐concept study for structural steels and butt welds to determine the cyclic material properties. The study proves the potential of the easy‐to‐use Hardness Method for local concepts, such as the Two Stage Model.
Structural response and design of stainless steel hollow section columns at elevated temperatures
Authors: Quan Chunyan , Kucukler Merih 
Published: September 2023

AbstractThis paper investigates the flexural buckling behaviour and design of stainless steel circular, elliptical, square and rectangular hollow section (CHS, EHS, SHS and RHS) columns at elevated temperatures through numerical modelling. Shell finite element models are utilised to perform numerical parametric studies whereby benchmark structural performance data are generated. A large number of cold‐formed and hot‐rolled austenitic, duplex and ferritic stainless steel CHS, EHS, SHS and RHS columns at elevated temperatures are taken into account, considering various cross‐section and member slendernesses. Since the fire design provisions provided in the European fire design standard EN 1993‐1‐2 for stainless steel columns are largely based on those originally developed for carbon steel columns, they typically lead to rather inaccurate ultimate resistance predictions for stainless steel columns at elevated temperatures. To address this, in the present study, a new flexural buckling design method for stainless steel hollow section columns at elevated temperatures is put forward. The accuracy, safety and reliability of the proposed design method and the provisions in EN 1993‐1‐2 are assessed. It is observed that the proposed fire design method leads to more accurate, safe‐sided and reliable flexural buckling resistance predictions for stainless steel hollow section columns at elevated temperatures relative to the provisions in EN 1993‐1‐2.
Influence of the geometry of butt welds and longitudinal attachments on their fatigue resistance
Authors: Hofmann Gloria , Kuhlmann Ulrike 
Published: September 2023

AbstractMany constructions, such as wind turbines, bridges and crane runways, are cyclic loaded so that fatigue failure may occur. Therefore, in the course of the revision of Eurocode 3, two research projects funded by AiF‐DASt re‐investigate the classification of constructional details of EN 1993‐1‐9. This paper focuses on the geometrical influence on the fatigue resistance of butt welds and longitudinal attachments. First, the influence of the plate thickness on butt welds was investigated. Both a meta‐study based on test results of various research projects and our own test series on butt welds up to 80 mm thickness led to interesting conclusions.Furthermore, the influence of the length and radius of longitudinal attachments on the fatigue resistance was investigated. By experiments and numerical analysis, clarification has been sought whether the transition radius larger than 150 mm or the ground weld toe is decisive for the improvement of the fatigue resistance. Since previous meta‐studies could not provide a clear result on the influence of the longitudinal attachment length, this was also investigated.A database established in the projects allows to integrate and assess the specified details of butt welds and longitudinal attachments in the context of the overall approach in EN 1993‐1‐9.
Fatigue Verification Concept for Details containing Weld Imperfections
Authors: Bartsch Helen , Feldmann Markus 
Published: September 2023

AbstractSteel structures subjected to repeated stress variations must be verified against fatigue in accordance with EN 1993‐1‐9 on the basis of a detail catalog. As one major concern, the background of the detail classification in terms of an extensive database does not provide information on the considered quality of welds. Certain weld imperfections are present in every construction. However, the extent of imperfection sizes that can be tolerated to provide sufficient fatigue resistance has not yet been scientifically determined.On an experimental and numerical basis, the presented concept allows the quantitative connection of fatigue classes with sizes of weld imperfections. For the two representative details of the load‐carrying‐cruciform joint and the non‐load‐carrying transverse stiffener, basic fatigue classes without explicit imperfections are calculated first. Furthermore, stress increase factors were determined that indicate the decrease in fatigue strength for weld imperfections of different type and size.A combination model is used to determine the fatigue strength of a detail with multiple weld imperfections. Using a simple formula and reading fatigue classes and reduction factors in tables, the fatigue strength of an imperfect detail can be easily determined.