bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of Technological Cracks in Welded Joints of Railway Bridges
Authors: Wichtowski Bernard , Hołowaty Janusz 
Published: September 2021

AbstractWhilst verifying the quality of welded joints in railway bridges in Poland, it was found that many of them contained cracks of technological, fracture and fatigue origin. This problem is associated with early welded bridge structures, in which many technological imperfections were discovered. General data for x‐ray testing on approximately 200 bridges in service are given. The tests were carried out over the period 1967–1990. The number of joints tested was 15 875 and the number of cracks discovered in the joints was 437 in the 34 bridges tested. Repeated tests on the joints containing cracks in time intervals of 5–8 years neither demonstrated further growth in the cracks nor the formation of new cracks. All the cracks discovered were formed during welding operations where there was no service loading. An analysis of the stress levels necessary for the development of crack growth was carried out via fatigue laboratory tests on three butt splice models which were similar to the joints in the bridges tested. Concurrently, the probable stress level near to the cracks was determined analytically. The calculated and measured stresses under service loadings did not exceed empirically assessed weld endurance limits for these joints and confirmed no crack growth. Hot cracks and other welding imperfections in welded joints in structures are permissible if there is neither growth in service nor resistance or rigidity loss of the structure.
The design of a steel lattice transmission tower in Central Europe
Authors: Tibolt Mike , Bezas Marios‐Zois , Vayas Ioannis , Jaspart Jean‐Pierre 
Published: September 2021

AbstractThe current paper resumes the design of a steel lattice transmission tower carried out in the framework of the RFCS‐funded research project ANGELHY. The scope of ANGELHY is the establishment of analysis methods for lattice towers and the development of design rules for steel and hybrid angle sections, as well as built‐up members composed of angles. In Europe, the design of transmission towers for overhead electrical lines can be carried out according to EN 1993‐3‐1: 2006 or for electrical lines exceeding 1 kV according to EN 50341‐1: 2012. Both standards prescribe linear elastic global analyses for the design of steel lattice towers. In the current paper, the linear elastic design of the suspension transmission tower according to the German National Annex of EN 50341‐1:2012 is presented. In a first step, common typologies of lattice transmission towers used in Europe are described. In a second step, the chosen tower typology is explained in detail. The Danube tower represents the widest spread tower typology in Europe. Finally, the detailed design procedure of the tower according to EN 50341‐1:2012 is presented. The design is carried out with the software TOWER – Version 15.0 from Power Line Systems.
Buckling Verification of Manhole Area of Tubular Steel Wind Turbine Towers via Non‐linear Finite Element Analysis
Authors: Koulatsou Konstantina G. , Chondrogiannis Kyriakos‐Alexandros , Gantes Charis J. 
Published: September 2021

AbstractAs wind turbine towers grow in height and their blades become longer, actions on the towers are also increased and their safe and cost‐effective design becomes critical for the further development of the wind energy sector. One potential failure mechanism of tubular steel towers is shell local buckling between ring flanges. In the present paper, the buckling behavior of a 120m tall wind turbine tower under realistic wind loads is investigated numerically, focusing on the buckling response near the man‐hole opening. To that effect, nonlinear finite element analyses accounting for geometrical and material nonlinearity and imperfections (GMNIA) is employed. GMNIA is performed taking into account initial geometric imperfections with the most unfavorable shapes resulting from the three primary buckling modes, determining the imperfection size according to EN1993‐1‐6 depending on the assumed fabrication quality class A, B or C. Numerical results are compared to analytical verification according to EN1993‐1‐6. Different wind directions are considered. Moreover, to investigate the influence of the stiffening of the manhole to the tower buckling strength, a comparison between three alternatives of stiffened and an unstiffened manhole is performed.
Experimental study on residual stresses of dual phase high‐strength cold‐formed steel angles
Authors: Xia Yu , Li Zhanjie , Schafer Benjamin W. , Blum Hannah 
Published: September 2021

AbstractThe rapid advance in advanced high‐strength cold‐formed steel makes this material promising for the construction industry to use as structural framing, but necessitates an accurate understanding of mechanical properties, including residual stresses. An experimental study was conducted to measure the residual stress which is generated during the member manufacturing process of a press‐braked angle member composed of advanced high‐strength cold‐formed sheet steel. The amplitude and distribution of membrane and flexural residual stresses around the member cross‐section is presented and the magnitude of residual stresses relative to the yield strength for the test specimen and other previous studies are compared. Additionally, the cutoff length typically recommended for residual stress measurements is investigated by comparing the residual stress distribution around the cross‐section for a section taken from the center and near the end of the member.
Comparative study between stressed skin effect of trapezoidal sheet and sandwich panel roof cladding
Authors: Nagy Zsolt , Kelemen Andrea , Zaharia Gelu , Bács Béla 
Published: September 2021

AbstractPrevious research studied the stabilizing effect of sandwich panel roof cladding and trapezoidal sheet cladding, considering pitched roof portal frame structures. It was observed that these cladding types contribute to the transfer of horizontal loads to the main structural elements, acting in a similar manner as roof bracings, while also providing significant lateral stability to the steel members. Certain methodologies were developed in order to introduce this effect into a 3D numerical model while taking into account the connections between the cladding and the purlins, as well as the influence of the fixing method between the purlins and the main structural members. The current study presents two procedures in order to achieve this and aims to present a comparison between these cladding types in terms of sway displacement of the frame structure with semi‐rigid joints and load transfer by applying the developed methodology to a reference building. The comparison is based on detailed analytical and numerical calculations, carried out by combining the design recommendations available for each cladding type and the developed analysis procedures using a 3D structural analysis software. The analysis results emphasize significant stabilization effects on the structure in both cladding cases.
Comparing Fire Behaviour of Restrained Cold‐Formed Steel Columns with Stiffened and Unstiffened Sections
Authors: Laím Luís , Craveiro Helder D. , Simões Rui 
Published: September 2021

AbstractAlthough, some experimental investigations have already been conducted and reported in the literature on cold‐formed steel columns under fire conditions, tests on the structural response of CFS columns in compression with intermediate and edge stiffeners and with restrained thermal elongation are rarely found in the literature, hence the relevance of the current investigation. In the present study, the effect of i) cross‐section shape (including single and built‐up sections), ii) web and edge stiffener configurations (webs with and without intermediate stiffeners and flanges with single edge fold stiffeners and double edge fold stiffeners), iii) slenderness (columns with different boundary conditions: pinned and fixed ends), and iv) stiffness of the surrounding structure to the thermal elongation of such columns have been investigated using an experimental campaign. Based on the research results it is clear that the overlapping regions, composite action, number of stiffeners, section geometry and load level take a crucial role in the fire structural behavior of CFS columns.
Fastener behaviour in sheathed light‐gauge steel stud walls under cyclic and monotonic actions
Authors: Ringas Nikolas , Huang Yuner , Becque Jurgen 
Published: September 2021

AbstractSteel framed buildings using digitally fabricated light‐gauge steel sections, combined with an offsite panelised fabrication approach, are becoming more widespread and contribute towards reducing cost and erection time without requiring a large workforce to assemble them. Currently, design standards mandate the use of K‐ or X‐bracing in these structures, thus neglecting the beneficial influence of the sheathing on the behaviour of the system, in particular its resistance to lateral loads. This composite behaviour is largely influenced by the performance of the fasteners, which may exhibit tilting, shear failure and fastener pull‐out. This paper takes a first step towards accounting for composite action between light‐gauge steel stud framing and calcium silicate board by focusing on the behaviour of the screws connecting both. Key failure modes are identified, based on direct pull‐out tests and monotonic and cyclic connector shear tests. Significant pinching behaviour was observed under cyclic excitations.
Behaviour of rectangular concrete filled tubular flange girders under combined loading
Authors: Al‐Dujele Rana , Cashell Katherine A. 
Published: September 2021

AbstractSteel‐concrete composite construction can provide an efficient structural solution by utilizing the two component materials to create a single effective composite section. The high tensile strength and ductility of steel combined with the excellent compressive strength and robustness of concrete results in an effective composite cross‐section which can be used in a wide variety of applications. There are a number of different shapes of composite beam, and this paper is focussed on a relatively new structural solution called concrete filled tubular flange girders (CFTFGs). These comprise a steel beam in which the top flange plate is replaced with a concrete‐filled hollow section. The compression flange can be any shape (e.g. circular, rectangular, and pentagonal) and the focus in the current paper is on simply supported girders with a rectangular section for the compression flange (i.e. RCFTFGs). These members have very high lateral torsional buckling resistance compared with conventional steel I‐girders of similar depth, width and steel weight and are therefore capable of carrying very heavy loads over long spans. However, they are complex to analyse and their behaviour is governed by several inter‐related parameters which are investigated and discussed herein. Given the most common applications of these girders, such as in bridges and carparks for example, they are frequently exposed to a simultaneous combination of high axial loads and bending moments. Although current design codes offer rules for the design of composite columns under combined loading, the design of RCFTFGs, which are asymmetric in nature under the combined effects of tension and bending, are not explicitly included. This work aims to investigate the ultimate strength of RCFTFGs with stiffened webs under the combined effects of various levels of axial tension and positive (sagging) bending moment. Nonlinear three‐dimensional finite element analyses using the ABAQUS computer software package have been developed to facilitate the study. The model is validated using available experimental data and then employed to conduct an extensive parametric study. It is shown that the moment capacity of RCFTFGs is reduced in most situations under the presence of an axial tensile force in the steel beam. In addition, the tensile capacity of the RCFTFGs is limited by the axial capacity of the steel beam alone, with little contribution from the concrete infill. Several influential parameters are examined and conclusions are discussed. Based on the finite element analysis, the moment–axial force interaction relationship is presented and discussed.
Experimental and numerical investigations on steel‐concrete interaction of embedded corrugated web composite members
Authors: Németh Gábor , Kovács Nauzika 
Published: September 2021

AbstractThe application of trapezoidal corrugated plate as the web for girders, thanks to a number of favorable features, modernizes the manufacture of steel‐concrete composite and hybrid structures and provides an alternative, competitive structure for small, medium and large span beams. However, the traditional headed stud shear connectors on the top flange can be considered obsolete in many ways. By embedding the corrugated steel web to the concrete slab, other types of connections should be used, and the behavior of these kind of connections are really promising. In fact, the embedded corrugated web itself functions as a shear connector, though other additive connectors should be used. To understand the structural behavior and design of these embedded connectors, the first step is the examination of the embedded web.The focus of the research presented in this paper is on the interaction behavior of embedded trapezoidal corrugated webs with additional mechanical shear connectors. As the first steps of the research comprehensive experimental program was completed in the Structural Laboratory of the Department of Structural Engineering in BME. This paper provides an overview for 8 (test) 12 (FE model) specimens of the push‐out test program with the aim to introduce the structural behavior of embedded corrugated steel web and the influence of structural parameters on the shear resistance and deformation capacity through experimental and numerical investigations.
Behaviour of fully encased composite columns under cyclic loads
Authors: Alsamawi Almoutaz bellah , Boumechra Nadir 
Published: September 2021

AbstractConcrete and steel have different advantages, concrete has high compression strength and low cost while steel has high tensile strength, rigidity and ductility. Composite members have other beneficial qualities beside all of them. Composite columns are used extensively in modern buildings essentially in industrial buildings. The main purpose of this study is an analysis and a comparison between the responses (load‐displacements) of different types of composite columns under cyclic loads. For this purpose, a three‐dimensional (3D) finite element model is developed for the columns, the finite element analysis of composite columns is carried out by using ANSYS code. The numerical model considers the elasto‐plasticity of materials and the non‐linearity of contact friction. It is interesting to observe a large ductility of these composite elements and the efficiency of some types of the composite columns than others. The aim of the study is to analyze the encased composite columns under cyclic loads focused on the different type of steel section. The parameters studied are the influence of axial load levels, skeleton curve, ductility, energy dissipation and the peak lateral load also carried out. The results indicate that the first columns of the specimens have a low specimen energy dissipation due the durability of the columns is higher than the axial load applied, and for better ductility and energy dissipation the axial load level of fully encased composite columns should be limited to approximately a value of 0.6.
Numerical investigation for the design of rectangular concrete encased steel composite columns
Authors: Ergun Ozgun , Schäfer Markus 
Published: September 2021

AbstractAdvanced design methods are becoming more important for the structural analysis. However, their results depend strongly on the quality of the numerical model and its underlying assumptions. Current Eurocode 4 does not provide clear guidance for this analysis type.A literature review on the compression tests conducted on concrete encased steel composite columns is presented. It was found out that there is a lack in the literature when it comes to the testing of slender composite columns as opposed to numerous tests done on stub columns. A selection of existing specimen tests are then simulated using finite element analysis software ABAQUS. Nonlinearity in the model was defined through materials and geometry. The interface modelling between steel and concrete as well as the modelling of load introduction are discussed. The finite element model was intended to be as generic as possible so that it can be taken as a basis for future parameter studies. Moreover, the column resistance check using interaction curves was discussed. Different approaches to form interaction curves namely strain limitation and plastic section capacity were compared.
Structural response of aluminium alloy concrete filled tubular columns
Authors: Georgantzia Evangelia , Ali Shafayat Bin , Gkantou Michaela , Kamaris George S. , Kansara Kunal , Atherton William 
Published: September 2021

AbstractThere is an increasing trend of using structural aluminium within the construction industry, due to its superior mechanical properties, such as high strength‐to‐weight ratio and high resistance to corrosion. The use of aluminium combined with concrete can be advantageous in terms of the resultant structural capacity. Currently, the design standards for the structural use of aluminium are substantially conservative and less exhaustive, which limits the full exploitation of aluminium as a structural material. This paper aims at developing more reliable structural design specifications based on experimental testing of aluminium‐concrete composite columns. A series of specimens comprising concrete‐filled aluminium hollow sections were experimentally investigated. Square hollow sections and rectangular hollow sections with different aspect ratios were considered. The hollow sections employed 6082‐T6 aluminium alloy and were filled with concrete of C30 grade. The specimens were subjected to gradually increasing axial compressive loading until their failure. The behaviour of the specimens was observed through continuous monitoring and recording of the strain and displacement through instrumentation mounted on the specimens at critical locations. The experimentally obtained load capacities were compared to those predicted by European design specifications. Conclusions with regards to the structural efficiency of concrete‐filled aluminium alloy columns are drawn and design recommendations in line with the observed structural response are made.
Concrete fatigue of composite constructions with rib shear connectors
Authors: Christou Georgios , Hegger Josef , Classen Martin 
Published: September 2021

AbstractRib shear connectors are gaining increasingly attention in the field of composite constructions. Especially in bridge constructions, rib shear connectors offer many advantages compared to conventional composite shear connectors such as headed studs. In order to describe the load‐bearing behaviour of rib shear connectors under cyclic loading, the successively increasing slip resulting from the cyclic loading of the shear connectors must be taken into account. The latter leads to the growth of the relative displacements along the composite joint and thus, to the degradation of the previously rigid shear connection. This effect leads to rearrangements of internal forces between the composite partners through which the load bearing behaviour and load bearing capacity of the structure alter. In this article results of experimental investigations on two cyclic single Push‐Out‐Tests (sPOT) and one full‐scale girder test regarding the degradation of the composite interconnection are presented and analysed. The investigated shear connectors in the full‐scale girder test are subjected to a comparable load history to that of the connectors in the sPOT. The results give insight into the effects of the degradation of the shear connection, as previously seen in sPOT, on the overall load bearing behaviour of composite girders.
Crack propagation and residual load‐bearing behavior of composite dowels – effects on the global behavior of composite girders under cyclic loading
Authors: Wolters Kevin , Christou Georgios , Feldmann Markus 
Published: September 2021

AbstractFatigue of a composite girder according to Eurocode 4 is carried out on the decisive shear connector. It is not taken into account that the composite girder is an internally highly statically indeterminate system in which the failure of a dowel does not necessarily lead to the failure of the girder. This applies in particular to composite dowels which are characterised by a crack propagation phase with a high residual load‐bearing capacity of a damaged dowel.In own small part and girder tests as well as numerical studies, numerous positive load‐bearing effects could be identified in composite girders with composite dowels, which increase the lifetime of the girder. In case of an initial crack in a steel dowel, followed by crack propagation, the stiffness degradation of the damaged connector leads to a redistribution of forces. The lifetime of a girder is limited by the residual capacity of the composite joint or by a global failure with increasing partial connection.A global safety concept for composite girders taking into account the crack development and residual strength of the dowels as well as the redistribution of forces within the composite joint holds an enormous economic potential. This article shows how these effects can be taken into account.
Partial shear diagram of slim‐floor beams
Authors: Zhang Qingjie , Schäfer Markus 
Published: September 2021

AbstractSlim‐floor beams which have the steel sections fully or partially integrated into the concrete slab lead to a significant reduction of the construction height. Due to its flat lower surface, it provides favourable solution for technical installation. According to EN1994‐1‐1, for composite beams plastic moment resistance is assumed. In the case of slim‐floor sections, due to the reduced construction height by the integration of the steel beam in the concrete and its extended bottom flange, a large compression zone height may be expected, thus concrete failure in the compression zone may happen before reaching the plastic moment resistance Mpl,Rd. Here, strain limit resistance becomes decisive. For design with partial shear connection, EN1994‐1‐1 provides the partial shear diagram based on the plastic bending resistance Mpl,Rd which is not always suitable for slim‐floor beams. Based on strain limited method, the more suitable partial shear diagram of different slim‐floor beams can be developed. From parametric studies of different types of slim‐floor beams, the impacts of critical parameters on the design are highlighted, and the limitations of the current plastic resistance based partial shear diagram are suggested. A simplified calculation method for situation beyond the limitation are also proposed to guarantee an economical design of those beams.