bluuebunny/crossref_metadata_2025_split huggingface dataset:
16.13: Queensferry crossing cable‐stayed composite bridge
Authors: Kærn Jens Christian , Hansen John Elnegaard 
Published: September 2017

ABSTRACTThe Queensferry Crossing near Edinburgh is a road bridge which is constructed as a composite cable‐stayed bridge with two main spans of 650 m and two approach bridges. The main bridge has a width of 40 m and has two skew cable planes with spacing of 16.4 m. The composite deck comprises a single open steel box with a concrete slab on the top.The bridge is designed in accordance with the Eurocodes design standards. The general design approach for the steel deck is based on the Reduced Stress Method in accordance with Eurocode 3 together with finite element (FE) shell method calculations for individual plates and for whole plate panels. The FE shell methods are in accordance with [7] Annex C model 5, which means that the calculation is based on nonlinear material properties and non‐linear geometric behaviour and finally includes plate imperfections.The typical steel deck box is stiffened with longitudinal trough stiffeners and cross bracing frames at a spacing of 4.05 m. Special details are made around the three Towers and the Transition zone between the single steel box in the cable‐stayed span and separated twin boxes on the approach viaducts.The steel structure for the cable‐stayed bridge was fabricated in China and steel segments with a length of 16.2 m were transported to Scotland, where the concrete deck was cast. Afterwards the segments were transported by sea to the bridge site, lifted to their final position and the two segment cables were installed and anchored to the deck and the towers.The Queensferry Crossing is the UK's tallest bridge and has been recognised in the 2016 Guinness World Records for the world's largest freestanding balanced cantilever. The north and south approach bridges were launched with a maximum cantilever span of 104 m.
16.22: Remarks on the material testing of historical railway bridges: Steelworks built from 1873 to 1950
Authors: Hołowaty Janusz , Wichtowski Bernard 
Published: September 2017

ABSTRACTA decisive role regarding the durability of historical railway bridges is played by degradation processes, which can only be resisted to a limited extent. Since the structural resistance of old bridges decreases naturally, devising design criteria for the assessment of their residual resistance would appear to be unnecessary. In many cases, existing steel bridges which do not obey design code requirements may safely carry current service loads. New methods for the structural capacity assessment of historic bridges have been designed in many countries, which take into account existing loads as well as those expected during the residual working life, along with the material properties of the bridges.The testing of material samples from 21 historic railway bridges allowed information on the mechanical properties of the steel along with the structures’ response to hitherto existing loads to be gathered. The chemical composition, steel static tension, hardness and toughness, and weldability assessment by factors are verified. All the tested bridges were built from early structural steels. In some bridges, early structural steel of higher strength has also been found in steel manufactured in 1875. The results of the old railway bridge steel tests given in this paper may be utilised in forecasting the further durability of similar structures.
17.04: Design of offshore wind turbine jacket foundations: On the influence of subsequent modifications on fatigue performance
Authors: Augustyn Dawid , Nielsen Martin Bjerre , Pedersen Ronnie Refstrup 
Published: September 2017

ABSTRACTThe design of jacket foundations for offshore wind turbine typically relies on design loads from an integrated aero‐elastic model of the full turbine structure and a reduced (superelement) representation of the foundation. In this paper the influence of introducing subsequent design changes to the foundation that potentially invalidate the design loads is studied based on a generic jacket foundation subject to combined wind and wave loading. The fatigue performance is considered for the reference case as well as a number of structurally modified configurations covering changes in braces, legs, soil conditions and footprint. The modified jackets are examined for both inconsistent design loads based on the reference geometry and updated loads associated with a consistent, aero‐elastic load iteration with the updated geometry and/or soil conditions. Ratios between the fatigue lives based on the inconsistent and the updated forces are presented, indicating whether an additional load iteration is essential or not. By having an overall understanding of allowable structural modifications a foundation designer is able to provide a more efficient jacket design by independently optimizing the structure in the post‐processing stage.It is shown that the subsequent jacket modifications may significantly affect the quality of the fatigue results. Some modifications, especially the ones associated with the boundary conditions, e.g. soil modifications significantly modify the global dynamic behaviour, thus indisputably require an additional aero‐elastic load iteration. On the other hand, modifications resulting solely in local changes such as minor brace or leg size modifications, especially when increasing the stiffness, may be allowed in the post‐processing phase without committing a significant error.
17.06: Characterization of accidental scenarios for offshore structures
Authors: Čekerevac Damjan , Rigueiro Constança , Pereira Eduardo 
Published: September 2017

ABSTRACTOffshore structures are complex facilities whose malfunction can lead to serious impacts and losses, such as human lives, environmental disasters and the complete loss of the structure. Additionally, the cost associated to their construction and maintenance is very high, so it is crucial to keep them fully operational throughout their entire service life. Standby periods in offshore platforms generate large financial losses for their owners. The most devastating effects on offshore platforms are often the result of incidents which eventually lead to accidental actions. Hence it is very important to develop measures which limit the effects of accidental actions on the overall performance of these facilities.In this paper the most likely accidental scenarios and the strategies currently used to mitigate their devastating effects were analysed. Accidental scenarios were discussed based on the available historical data of incidents on offshore platforms, and classified according to the type of offshore platform or the type of structural elements affected. Furthermore, the most frequent hazards were used to introduce specific accidental actions which will then be the subject of a study for comparing the approaches proposed by different technical standards. The strategies currently used for mitigating the effect of accidental actions, both non‐structural and structural, were classified according to the materials used and the structural typology adopted.The objective of this study was to identify new opportunities for the development of innovative mitigation strategies for the devastating effects associated to accidental actions in offshore platforms, considering the most recent developments in terms of innovative materials and of structural analysis approaches. In this context, this paper discusses the current trends in research and the future challenges related to this issue. This will serve to identify the possible methods for improvement of the existing structural mitigation measures.
01.05: Experimental and theoretical study of large capacity extended end‐plate moment connection
Authors: Samaan Rimon A. , El‐Serwi Ahmed A. I. , El‐Hadary Riham A. 
Published: September 2017

ABSTRACTOver the years, bolted end‐plate moment connections have been very popular due to the ease of fabrication and erection. The need for large capacity connections with four bolts in one row had become mandatory as a reason of recent complicated structures with large spans and limited available depths. The current research includes an extensive parametric study for the extended large capacity bolted moment connections. For this purpose, three‐dimensional finite element models are prepared using the non‐linear, multi‐purpose, finite element compute package, ANSYS‐11.0. In order to validate the developed finite element model, an experimental program containing five full‐scale flushed and extended, end‐plate connections subjected to bending moment and shear force is performed. The finite element model used throughout the parametric study is verified by comparing its results with the results of the performed experimental study in addition to experimental results recorded by other researchers showing good agreement. The effect of end‐plate thickness, bolt diameter as well as adding horizontal stiffener at two different positions on the connection moment capacity and tension bolt force distribution is studied. Several curves are plotted to show the relation between connection ultimate moments and end plate thickness for different connection configurations. Regression analysis is performed for results and design equations were proposed for each connection configuration.
21.04: Vibration characteristics of an existing high‐rise building in Montreal and the effects of retrofit
Authors: Manolache Laura , Wang Yudong , Tirca Lucia , Bagchi Ashutosh 
Published: September 2017

ABSTRACTThe study described in this paper refers to seismic assessment and retrofit of an existing 10‐storey reinforced concrete office building designed and built at the beginning of the 20 century. When this building with a height of 38.95 m was completed it was the highest in downtown Montreal. According to FEMA 547 classification, the typology of this building structure is associated to model building type “C3”. Consequently, this type of non‐ductile frame building with an insignificant amount of masonry walls is relatively weak and unable to carry the seismic forces when subjected to ground motions from a potential earthquake magnitude. The main deficiencies of this structural system are: poor lateral confinement and shear resistance of columns, the location of lap splices and the number of reinforcing bars often inadequate, the lack of confinement and shear reinforcement in joints, poor anchorage of longitudinal reinforcement of beams into joints and shear resistance of beams. Due to lack of seismic detailing, the common retrofit measure recommended in ASCE/SEI 41–13 for this building is to add new lateral force‐resisting systems designed according to current code and standard provisions. Hence, in this case, the most cost‐effective retrofit solution is to add a steel structure designed to withstand seismic forces while responding to serviceability criteria required to preserve the non‐reinforced masonry facades facing the main streets and the facades ornaments.
21.12: Behaviour of CFS strengthened hot‐rolled structural steel beams under flexure
Authors: Selvaraj Sivaganesh , Madhavan Mahendrakumar , Gopalan Anadh Gopal Venu , Jayabalan Aswin Kumar , Arumugam Pavan Kumar 
Published: September 2017

ABSTRACTA strengthening system using cold‐formed steel (CFS) channel as an encase to inhibit the lateral‐torsional buckling (LTB) of hot rolled steel (HRS) channel is experimentally examined by conducting a four‐point bending test. An advantage of this technique is that this retrofitting method can be applied in‐situ by minimal manpower. The retrofit technique involves encasing the CFS channel to the HRS channel followed by interconnecting the two with spot welding. In general, the test results of the HRS channel retrofitted with CFS channel indicate that in addition to preventing the LTB mode of failure the moment capacity of the section increases by 60% compared to the control specimen. It was also found that the effectiveness of the retrofitting technique increases with an increase in the slenderness of the HRS channel along with an increase in the number of interconnecting spot welds. In addition, the test results indicate that the current specification for both HRS and CFS are not suitable for an HRS‐CFS built‐up section. Based on the test results a new interconnection spacing limitations to avoid the local buckling of the CFS channel is suggested.
21.15: Resource efficiency in the building sector: Application to steel buildings
Authors: Gervásio Helena , Dimova Silvia , Pinto Artur 
Published: September 2017

ABSTRACTIn light of current European guidelines towards resource efficiency in the construction sector, a performance based approach is herein introduced taking into account environmental criteria, namely the sustainable use of resources. The proposed approach for sustainable design is in line with the safety assessment criteria of the European standards for structural design. Moreover, the approach, which is based on a standardised procedure for life cycle assessment, aims to harmonize the assessment of the sustainability of buildings in Europe and to enable an easier integration of sustainability and structural criteria into the design process of buildings, following the basic requirements for construction works of the Construction Products Regulation.It is considered that resource efficient building design and construction comprehends the reduction and/or minimization of the use of resources and corresponding environmental impacts, while improving the lifetime performance of buildings through technical and functional achievements. Thus, not only the reduced use of raw materials and other natural resources but also technical and functional aspects such as building adaptability, ease disassembly and deconstruction contribute towards this goal. These are all aspects from which steel structures may benefit.Hence, the first part of this paper focusses on the presentation of the general framework for sustainable assessment of buildings. Then, in the second part, the life cycle performance of steel buildings is discussed, in light of the proposed approach, and potential aspects leading to improvements are identified. Conclusions are drawn in the end of the paper.
P05.02: Different cross‐section in lateral‐torsional buckling
Authors: Bajer Miroslav , Barnat Jan , Vild Martin , Melcher Jindřich , Karmazínová Marcela , Piják Jiri 
Published: September 2017

ABSTRACTThe goal of the research presented in this paper is the experimental and theoretical analysis of cross‐section which can be asymmetric. Particularly, there are experimental tests of several beams of selected cross‐section shapes described and analysed. The main idea of those experiments was to observe the differences in behaviour between monosymmetric cross‐section and the asymmetric one. Currently used design methods for a solution of lateral‐torsional buckling are based on critical moment approach. This solution is also implemented in design codes but it is limited for use of double and monosymmetric cross‐sections.Another part of the paper is focused on the numerical evaluation of transversally loaded beam of one monosymmetric and four asymmetric cross‐section shapes susceptible to lateral‐torsional buckling. Several analytic methods used for evaluation of the beam bending resistance in design software were evaluated.This paper presents the comparison of numerical and experimental results of transversally loaded beams with monosymmetric and asymmetric cross‐sections. Stresses in selected parts of the cross‐section are evaluated and compared together. This comparison shows that the normal stress on both (monosymmetric and asymmetric) cross sections is the subject of the same rules – a combination of stresses inflicted by bending and torsion caused by an eccentricity between the point of load application and the centre of shear.
01.14: Tests of alternately loaded single‐cut joints with blind bolts
Authors: Swierczyna Szymon , Wuwer Walter 
Published: September 2017

ABSTRACTJoints in the frames designed with the cold‐formed profiles with a thickness 4÷5 mm, formed by a lap connection of their members by means of mechanical fasteners, are characterised by a considerable degree of flexibility. In static calculations of exemplary bearing structures resistance of the joints was included on the basis of experimentally established relations: force‐deformation and moment‐rotation, that vary nonlinearly under the influence of loads. Some of this loads, e.g. wind, may change their direction. Then, the effects of the next variable load are superimposed on action of the permanent load and effects of previously existing cycles of the variable actions. In a given joint of a bar structure the directions of resultant forces acting on the individual fasteners are changing, and its behaviour is described by defined hysteresis loops. Calculations of such a structure requires i.a. incremental load‐deformation analysis. Then, internal forces in particular members and deformations in the joints may be significantly different from the case, when horizontal wind load acts only in one direction.To describe the behaviour of a bar structure with the flexible joints loaded alternately, it is necessary to develop an experimentally verified method for prediction of hysteresis loops for the joints loaded by shearing force and bending moment. Appropriate design procedures of such joints, including proper criteria of their strength and limit deformation are needed.The paper presents the preliminary results of the tests of the specimens with the alternately loaded joints, in which the cold‐formed profiles are connected by means of proper number of the blind fasteners BOM type. The alternating load of the joint in the test specimen – simultaneously by the shearing force and bending moment – change the direction of the resultant forces, acting on the individual fasteners. Values of the load and its history have been selected to correspond the situation, which may occur in the actual structure of the frame loaded simultaneously by the permanent load, snow and wind.Results of tests are presented on the diagrams of relation: force‐deformation in the axis of the individual fastener and moment‐rotation in the joint. The preliminary conclusions are formulated and program of further investigations is presented. The aim of the research is to develop the structural system of lightweight steel buildings with latticed bearing structures.
01.17: Photogrammetric analysis of thin end‐plate deformations in steel and composite joints
Authors: Barcewicz Wioleta 
Published: September 2017

ABSTRACTThe subject of the paper concerns the issues related to the deformability of the semi‐rigid beam‐to‐column joints with bolted end‐plate connections. Deformations of the relatively thin end‐plates of different thickness (ranging from 40 to 60% of the bolt diameter) and height (flush and extended) are analysed in steel and composite steel‐concrete joints with varying reinforcement ratio of the composite slab. The joints were originally subjected to hogging bending in the destructive experimental tests, carried out at the Warsaw University of Technology a few years ago. The obtained results, based on the moment‐rotation relationships, were investigated and reported elsewhere.The aim of the research presented here is a determination of the distribution and the values of the maximum plastic curvatures of the deformed end‐plates by means of the photogrammetric analysis. Application of the digital photogrammetry, called stereophotogrammetry, enabled reconstruction and 3D‐modelling of deformed plate surfaces as well as a presentation of the results in graphic and numerical formats. The results of the photogrammetric analysis allow for determining the yield line patterns, which are the basis for defining the effective lengths of particular end‐plate parts, modelled as equivalent T‐stubs. Such models are used for identification of failure modes as well as a calculation of the basic joint properties by means of the component method, adopted in EN 1993‐1‐8. The examined semi‐rigid joints with the end‐plates of the thickness approximately twice smaller than the bolt diameter, demonstrated the mechanism of complete yielding of the T‐stub flange, representing the end‐plate (related to Mode 1 according to EN 1993‐1‐8). However, the intensiveness of the yield line patterns differs visibly when the same types of end‐plates were used in case of steel and composite joints. The influence of the end‐plate deformations was smaller in the composite ones and decreased with increasing reinforcement ratio.Comparison of results based on the approach used in Eurocodes and those reported on the basis of photogrammetric analysis is presented.
01.18: Optimization of the pre‐loading procedure for high‐strength bolts of FREEDAM connections
Authors: Cavallaro Giovanni Ferrante , Francavilla Antonella Bianca , Latour Massimo , Piluso Vincenzo , Rizzano Gianvittorio 
Published: September 2017

ABSTRACTA FREE from DAMage (FREEDAM) friction connection is a particular type of sliding hinge joint where in correspondence of the lower beam flange is realized a friction damper with steel angles and coated plates, pre‐stressed with high strength bolts. In order to master the resistance of a FREEDAM connection it is crucial to know accurately the value of the friction coefficient of the materials employed to realize the damper and to control the preload applied to the friction interface by means of high strength bolts.Dealing with this last topic, according to Eurocode 3 and EN 1090‐2, High Strength bolts (both of HR or HV type), when installed in friction bearing connections, must be installed based on one of four proposed procedures. The methods currently recommended are torque, combined, HRC and DTI and each of them, as already partially reported in technical literature, can lead to a different level of accuracy. Additionally, once the bolt is tightened it is well known that it undergoes to an “instantaneous” (short‐term relaxation) and to a “long‐term” loosening that, obviously, may affect the response of the FREEDAM connection which has to be designed not to slip under service loading conditions. Within this framework, the goals of the paper are multiple. First of all, by means of experimental analysis, it is wanted to assess the accuracy of some of the codified tightening methods, namely torque and combined, when applied to FREEDAM connections. Additionally, the possible bolts’ loosening occurring in short/medium periods of time (up to one month) are evaluated performing specific tightening tests. Finally, the effectiveness of Belleville spring washers in keeping the pre‐loading constant during the life‐time of the FREEDAM connection is assessed. In order to analyse all these aspects, an experimental analysis carried out at the STRENGTH laboratory of the University of Salerno, regarding 84 tightening tests performed on specimens of friction dampers is presented. All the specimens have been tested measuring with annular load cells the initial force applied to the bolts in order to evaluate the achievement of the target preload. Additionally, in some cases, the loss of pre‐load over a period of time has been monitored.