bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cable structure design of suspension bridges through strand reduction method
Authors: Acun Acuner 
Published: September 2021

AbstractCable structures hold a special place for the cost of suspension bridges. Considerable development of the structural cable material leads to design and construction of long‐span suspension bridges. Thus, designing cable structures that are cost‐effective and reliable is significant for these mega structures. The overall layout of a main cable is consistent with constant number of elements per span since the design of the first suspension bridge. However, the reduction of main cable area in regard to design loads could play an important role in saving cost of long span suspension bridges. This paper presents the strand reduction approach for the cable structure design of suspension bridges. The proposed approach has been implemented by releasing the required number of parallel wire strands in main cable of the suspension bridge at specific locations in accordance with axial loads on main and hanger cables where released strands are transformed into a hanger cable with special types of clamps. The strand reduction approach is named as “saddle‐clamp system” and has been compared with the current design of 1915 Canakkale Bridge. The results indicate that the strand reduction method provides 7.6% to 34.1% material quantity deduction for the cable structures of the suspension bridge.
Design of stiffened plates subjected to axial compression and transverse load
Authors: Kleppe Svein‐Rune , Aalberg Arne , Eltvik Liv 
Published: September 2021

AbstractStiffened plates (orthotropic plates) are used in many structures, for instance as plate girders and box girders in bridges, in ship hulls, and in bridge decks to minimize the dead load. Used as flanges or part of flanges in larger cross‐sections, stiffened plates develop membrane compression or tension, and in some cases in‐plane shear due to bending or axial actions on the cross‐section. The strength analysis of an orthotropic bridge deck has to take into account both buckling of the stiffened plate as a unit, local buckling of subpanels of the deck plate or the stiffeners, stiffener instability, and effects of transverse loading (e.g. dead load plus traffic load) on the stiffened plate.Adequate rules to determine the capacity of stiffened plates subjected to the combination of axial force and transverse load, as in bridge decks, are scarce or non‐existing in the present Eurocodes for design of stiffened plates and should be developed. An approach applying detailed FE‐analyses will often not be feasible in practical design due to an often weak correlation between the various loads, e.g. dead load, traffic load and loading in horizontal direction (wind), a large number of loading patterns for moving loads, different load combinations and loading levels in adjacent spans, as well as many different cross sections along the bridge.As a pre‐study of the mentioned load combination of axial force and transverse loading it have been simulated a stiffened plate (4 by 5 meter) motivated by the orthotropic deck of a bridge box girder for a suspension bridge. The axial stress was varied from 0 N/mm2 to 250 N/mm2 and combined with application of transverse loading until the stiffened plate collapsed in a flexural buckling mode. The capacity was determined following the provisions in Eurocodes prEN 1993‐1‐1, EN 1993‐1‐5, EN 1993‐1‐7 and the offshore standard DNV‐RP‐C201.It is evident that the modeled typical bridge deck, which is much wider than it is long and has large longitudinal stiffeners, behaves like a beam‐column between the supports. Even if the modeled stiffened plate is made almost quadratic, column‐like behavior prevails, and plate‐like behavior can be neglected.Capacity checks of a stiffened bridge deck, considering a strip of the deck comprising plate and one belonging stiffener, involve a highly mono‐symmetric cross‐section. Capacity should consider yielding both at the plate side and at the stiffener side. The DNV standard does this, and capacity determined from its equations agrees quite well with the FE‐simulations. The design provisions in the new prEN 1993‐1‐1 (Appendix C), which refer to its ordinary beam‐column formulas, must be modified to account for yielding at both sides of the stiffened deck to produce accurate results over the entire range of axial compression and transverse load. When modified, capacity predictions are on the safe side, yielding capacity approximately 70 % of the FE‐predictions.
Development of a transition piece for a self‐erecting wind energy plant
Authors: Korte Sebastian , Pak Daniel , Friehe Mirko , Fontecha Robert , Feldmann Markus , Reese Christian , Schmitz Katharina 
Published: September 2021

AbstractFor the construction of wind towers with large hub heights up to 200m, the FOSTA research project P1392 HYTOWER [1] investigated a concept for a self‐erecting wind energy plant with steel‐steel hybrid tower. A tubular steel tower is lifted inside a lattice tower using a strand lifting system. During this process the tubular steel tower is stabilized by hydraulic cylinders. A specially developed transition piece is used to accommodate the lifting system during the lifting process and to finally connect the two tower parts. In this paper, the erection process as well as the development of the transition piece is presented.
Numerical models for the analysis of shear walls in light steel residential buildings
Authors: Baldassino Nadia , Zandonini Riccardo , Zordan Marco 
Published: September 2021

AbstractIn recent years, the use of steel light housing structural solutions made of cold‐formed thin‐walled profiles (CFS) is becoming increasingly popular. Lightness, high structural efficiency, durability, rapidity and simplicity of erection of the building and its finishes are some of the main advantages of these systems, which make them attractive and competitive with respect to more traditional constructional solutions. In these buildings, which do have a skeleton made of cold‐formed steel profiles completed by sheathings made of various materials, the key role of transmission of both vertical and horizontal loads from the floors to the foundation, is played by the shear walls. Recently, the University of Trento carried out a project aimed to develop an industrialized housing system made of CFS members. In this framework, experimental and numerical studies of the in‐plane lateral response of shear walls were performed. In particular, this paper summarizes first the experimental program and then it focuses on the main features of numerical models and on their validation in both monotonic and cyclic regime. The critical parameters governing the response of these complex systems are finally identified and discussed.
Study of the shear behaviour of floor diaphragms in light steel residential buildings
Authors: Baldassino Nadia , Zandonini Riccardo , Zordan Marco 
Published: September 2021

AbstractSteel housing solutions made of thin‐walled cold‐formed profiles (CFS) appear to be very competitive in seismic areas due to their lightweight and the associated reduced mass. This non‐negligible advantage associated with the competitive costs and the ease of erection made popular this type of building solution. Aimed at investigating the potential of these structural systems, in recent years, several extensive studies of the lateral response of shear walls were carried out. On the contrary, little attention was paid to the behavior of the floor diaphragms and on their contribution to the overall building response. The University of Trento, in the framework of a wider research project aimed at the development of a residential building system made of CFS profiles, investigated the response of CFS floor systems subjected to in plane shear loading. Four types of floors characterized by two different beams systems and two different types of deck were tested in both monotonic and cyclic regime. Experimental results enabled the calibration of FE models simulating both the floor components and the whole floors. In this paper, the main features and outcomes of the tests and of the numerical analyses are presented and discussed.
Contribution of OSB Sheathing to Racking Capacity of Cold‐Formed Steel Frames
Authors: Kechidi Smail , Banks Nigel , Iuorio Ornella 
Published: September 2021

AbstractIn recent years, new innovative systems to ensure high structural and environmental performance have emerged in constructional steel practice. Among others, modular construction using cold‐formed steel (CFS) frames which offer some advantages over conventional structural system counterparts, such as high strength‐to‐weight ratio, controlled material quality and sustainability. Wood‐sheathed shear wall is one of the lateral load resisting systems adopted in CFS modular construction. It is composed of CFS C‐shaped framing members (chord studs, studs and tracks) attached to wood sheathing using fasteners. The resistance capacity of these shear walls, when subjected to in‐plan lateral loads, is governed by the connections between the frame and the sheathing board. It is therefore crucial to quantify the shear capacity of sheathing‐to‐frame fasteners. In this context, a testing rig was developed consisting of two CFS lipped channels facing back‐to‐back connected on the flanges by oriented strand board (OSB) and loaded such that the 8 connecting fasteners experience shear. The prevailing role of sheathing thickness and fastener type is highlighted in the results. The experimental results are summarized for further use in the analysis of shear walls under lateral load.
Numerical Modelling and Optimisation of Cold‐Formed Steel Purlins
Authors: Almatrafi Meshal , Theofanous Marios , Dirar Samir , Bock Marina 
Published: September 2021

AbstractThis paper reports a numerical study on the optimization of the lip size of Z‐sections under gravity loads. Numerical models simulating the structural response of cold‐formed steel Z purlins partially restrained by cladding and angle struts and subjected to sagging moment were developed and validated against a total of nine previously reported experimental results on Z‐sections that failed in local or/and distortional buckling. Models of varying levels of complexity were generated and the key parameters affecting the structural response were determined by means of a sensitivity analysis. The investigated parameters included the magnitude, shape and combination of initial geometric imperfections pertinent to local and distortional buckling and the simplified or explicit modelling of test details such as struts and sheeting. Having determined the appropriate modelling strategy that yields the best balance between accuracy and computational cost, parametric studies were conducted to investigate the effect of decreasing or increasing the lip depth on the sections' moment resistance and corresponding failure mode. Based on the parametric study results, the optimal lip size which maximizes the moment/weight ratio for each section was determined.
Constrained finite element method with displacement mapping
Authors: Hoang Trung , Adany Sandor 
Published: September 2021

AbstractA widely used approach to understand and analyze the complex behavior of a structural member is to decompose the complex phenomenon into simpler ones, and then to interpret the complex phenomenon as the superposition of the simpler ones. Accordingly, the deformations of thin‐walled members are frequently decomposed into global, distortional, local‐plate, etc. modes. One well known practical technique is the constraining of shell models; the idea first appeared in the constrained finite strip method, then later in the constrained finite element method, or cFEM in short. While the cFEM was proved to be applicable for a wide range of problems, its disadvantage is that it requires a specific rectangular shell finite element. The aim of the reported research is to release the limits set by this specific shell element. The idea is to use two discretizations and two corresponding basis function systems. One is based on an ordinary shell finite element, the other one is on the cFEM shell elements. The basis functions of the cFEM are mapped to the ordinary shell model, then the calculations are completed in the ordinary shell model but with using the cFEM basis functions. In the paper the proposed method is briefly introduced and some proof‐of‐concept examples are presented.
Optimized Design of Cold‐Formed Steel Elements for Serviceability and Ultimate Limit States
Authors: Mojtabaei Seyed Mohammad , Hajirasouliha Iman , Becque Jurgen 
Published: September 2021

AbstractCold‐formed steel (CFS) sections are gaining ever increasing popularity in modern construction practice due to their advantages, such as efficient material use and sustainability. While the manufacturing flexibility of CFS cross‐sectional shapes brings innovative and complex shapes within practical reach, obtaining optimum design solutions can be a challenging task due to the complex mechanical behaviour of CFS elements, which is controlled by local, distortional and global buckling modes, as well as the need to account for manufacturing and end‐use constraints. This study presents a practical framework for the development of optimised CFS beam sections with maximum flexural strength and minimum deflections in ultimate and serviceability limit state conditions, respectively, in accordance with Eurocode 3 (EC3). A population‐based Genetic Algorithm optimisation method is employed to obtain optimum solutions for ten different CFS cross‐section prototypes, while the EC3 geometric restrictions and a number of manufacturing and end‐use constrains are also considered. It is shown that sections optimised based on serviceability limit state (SLS) and ultimate limit state (ULS) requirements can provide up to 44% higher effective stiffness and 55% higher bending moment capacity, respectively, compared to standard commercial lipped channel sections with the same amount of material. The results also indicate that using optimised plain channels and folded‐flange sections generally leads to the best design solution in SLS and ULS optimization, respectively.
Numerical study on bending resistance of cold‐formed steel back‐to‐back built‐up elements
Authors: Lukačević Ivan , Ungureanu Viorel , Valčić Anđelo , Ćurković Ivan 
Published: September 2021

AbstractCold‐formed steel back‐to‐back built‐up beams are efficient and very attractive structural elements which can also offer excellent efficiency in production, both in capacity and material savings. The connection between such built‐up steel components can be easily obtained by screws or bolts, but the developments in the welding processes also lead to other solutions like continuous (laser or MIG brazing) or discrete (spot welding). This paper presents a parametric numerical study on such elements where various shapes and cross‐section geometries will be analysed, using different types of connection between the built‐up steel elements. The results from the evaluation of local and global buckling behaviour of such beams will serve as a base for planning future experimental work. Based on the numerical model, the paper presents the influence of several parameters i.e., the type of the channel section (lipped or plain channels), length of the beam, continuous and discrete connections between channels, the number and the distance between discrete connections along the beam axis and along the beam height. From the parametric study, it is concluded that capacity of the cold‐formed steel back‐to‐back built‐up steel beams is highly affected by the type of connections.
Pushing the Boundaries of Accuracy: Development and Calibration of an Imperfection Measuring Rig
Authors: Meza Francisco J. , Becque Jurgen 
Published: September 2021

AbstractIt is well understood that the buckling response of steel members can be significantly affected by their initial geometric imperfections. Therefore, it is of paramount importance that these imperfections are accurately measured and subsequently accounted for when studying the buckling behaviour of steel members. This paper discusses the design, development and calibration of an imperfection measuring rig. The set‐up makes use of a laser displacement sensor which is moved by two electric motors along orthogonal high‐precision guiding bars and is able to record out‐of‐plane imperfections over a length of 3 m. The initial accuracy of the imperfection readings, although of very reasonable quality, was found to be limited by the out‐of‐straightness of the guiding bars along which the laser sensor is moved. However, a novel calibration technique, where the system is calibrated against a liquid surface, was found to raise the performance of the rig to unprecedented accuracy. The technique is easy to implement and inexpensive. The calibration process, as well as an analysis of the repeatability of the results and an estimate of the magnitude of the error, are presented in this paper.
Experimental investigation into the performance of cold‐formed steel walls sheathed with OSB and cement‐based panels
Authors: Iuorio Ornella , Kechidi Smail , Banks Nigel 
Published: September 2021

AbstractCold‐formed steel (CFS) structures are developing fast in both seismic and not seismic areas for their high degree of prefabrication, high structural performance and the good energy performance. In the last decades, many research groups around the world have focused on the analysis of seismic behaviour of CFS structures and the development of design procedures that still need to find their full implementation in many international codes, first of all in the Eurocode. Therefore, the development of CFS system still requires, very often, the adoption of large experimental testing, in particular, when sheathing braced design methodologies are applied. This paper presents, for the first time, the in‐plane tests of CFS walls sheathed on one side with oriented strand boards (OSB) and cement based panels (CP). In particular, a set of two full scale tests of ledger walls having 2400mm width and 2926mm height, sheathed with OSB3 and CP, and a set of two tests on ledger walls having dimensions (2400mmm x 2974mm) sheathed with OSB3 panels are presented and discussed. The tests have been carried out in accordance to the BS EN 594:1996. The results confirm in agreement with literature studies that the collapse is governed by the failure of the screws between panels and steel profiles. And, more importantly it shows that, when both OSB and CP are present the collapse is governed by the failure of the screws between cement panels and steel profiles. When comparing the two sets of walls those sheathed only with OSB panels have lateral resistance which is about 1.5 time higher than when also CP are present.
Rheological modelling of high‐temperature stationary creep tests of Grade S275JR steel
Authors: Torić Neno , Burgess Ian 
Published: September 2021

AbstractThe paper presents a new validation study of a unified rheological model, in reproducing creep strains from a recent experimental study performed on grade S275JR coupons. The objective of this research is to further test the modelling capabilities of the proposed rheological model and its validity for application in general structural fire engineering analysis. The rheological model is composed of two serially connected Kelvin‐Voight elements, used to represent the material's sensitivity to strain‐rate‐governed changes of yield strength, temperature and heating rate. The paper presents the performance of the model in stationary‐creep conditions.
In‐plane Seismic Performance of SC wall to foundation connections
Authors: Wang Neng , Zhou Feng , Xu Haitao , Xu Zhengyu 
Published: September 2021

AbstractSteel‐plate composite (SC) structures have been studied and used in nuclear power plants since the 1990s. However, the seismic performance of the connection between SC wall and foundation has not drawn adequate attention. In this paper, four large‐scale SC‐wall‐to‐foundation connections were designed and tested under combined constant axial‐compression and cyclic in‐plane lateral‐force. Two types of construction details were considered, namely lap‐splice and embed‐ding. Through the general observations, all the specimens failed by flexure, as the crushing of concrete, yielding of dowel rebars or steel plates occurred. The in‐plane seismic performance of the connections including the load‐carrying capacity and ductility were summarized and analyzed. The existing equations for calculating the shear and flexural strength of SC walls subjected to in‐plane loading were evaluated with test results. Since test results show that both of the connection types are feasible for practical use, further investigations on the design of lap‐splice and embedding connections were recommended.
Hysteretic Behaviour of Shear Stud Connectors in Composite Steel Moment‐Resisting Frames
Authors: Jisr Hammad El , Lignos Dimitrios G. 
Published: September 2021

AbstractIn steel moment resisting frames (MRFs) with composite floor slabs, seismic loads are transmitted from the slab into the beam through shear studs. Shear strength degradation of the studs due to cyclic loading results into the loss of the load transfer mechanism and composite action. To date, several low‐cyclic, high‐amplitude push‐out tests have been conducted to characterize the shear stud hysteretic behaviour. These isolated tests showed considerable degradation in the shear stud resistance; nevertheless, they do not simulate the actual hysteretic behaviour of shear studs within a composite steel beam. To elaborate, conventional cyclic push‐out tests do not replicate the actual stress state in the concrete slab, nor do they account for the force redistribution between the shear studs. This paper investigates the hysteretic behaviour of shear studs in steel MRFs with composite floor slabs. The load‐slip hysteretic behaviour of the shear studs is examined through continuum finite element (CFE) models of 2‐bay sub‐systems and their corresponding cruciform subassemblies. Moreover, shear force and interlayer slip envelopes are obtained along the composite steel beams. Results of the CFE models are used to propose new design recommendations for shear studs in composite‐steel MRFs.
Testing a Prefabricated Ultra‐Shallow Composite Flooring System with Lightweight Concrete and Shear Studs
Authors: Ahmed Inas M. , Tsavdaridis Konstantinos Daniel 
Published: September 2021

AbstractThis paper presents an experimental investigation on a recently developed prefabricated shallow steel‐concrete composite flooring system composed with lightweight concretes. The novel flooring system is consisted of two main structural components: two C‐channel steel beams and a partially encased concrete floor. The concrete floor, which is in the form of T‐ribbed slab sections, was constructed using three types of concrete (reinforced normal concrete, reinforced lightweight aggregate concrete, and reinforced ultra‐lightweight aggregate concrete), and the steel edge beams which partially encase the floor slab and provide clear and straight finish edges. Three full‐scale push‐out tests were conducted to investigate the effect of the lightweight concrete on the longitudinal shear behaviour of the new shear connection system, made of web‐welded shear stud connectors. It was observed that specimens with lightweight concretes demonstrated additional ductility when compared with specimen using normal concrete, and the failure mode of the shear studs alters. It is confirmed that the specimen with normal concrete has reached a higher failure shear load.