bluuebunny/crossref_metadata_2025 huggingface dataset:
Vibration-based structural health monitoring from operational long- gauge fiber optic strain data
Authors: Reynders Edwin , Anastasopoulos Dimitrios , De Roeck Guido
Published: October 2021

Vibration monitoring from strain data is a promising alternative to acceleration-based monitoring because a dense measurement grid can be achieved at a relatively low cost and because strain mode shapes are more sensitive to local stiffness changes than displacement mode shapes. However, the feasibility of monitoring strain mode shapes of full-scale civil structures, where the operational dynamic strain levels are of very low amplitude and temperature changes can influence the modal characteristics, has remained an open question. The present work provides a proof of concept in which the deck of a steel bowstring railway bridge is instrumented with 80 Fiber-optic Bragg Grating strain sensors, multiplexed in four fibers, that are interrogated with a technique that achieves high accuracy and precision. For more than a year, the natural frequencies and strain mode shapes of 10 modes have been automatically identified from operational strain time histories, with typical root- mean-square values of 0.01 microstrain, on an hourly basis. Furthermore, using these modal data, the influence of temperature fluctuations and that of a retrofitting of the hangers connecting the bridge deck and the bow, which took place during the monitoring period, are extensively investigated. Both have an influence on the overall stiffness of the bridge and therefore they result in clear changes in the natural frequencies. They do not have an influence on the local stiffness and therefore they do not influence the strain mode shapes, except when the retrofitting induces an interaction between previously well-separated modes.
Structural design criteria for road bridges made of UHPC large prefabricated parts - approaches to possible CO2 savings potential in bridge construction
Authors: Olipitz Michael
Published: October 2021

The future development of girder bridges is determined by the goals of more sustainable and more resource-efficient forms of construction, which can be achieved by optimizing material, structure and manufacture. The practice of early, costly repairs or replacement buildings, which has been common in reinforced concrete construction for decades, allows the realization to mature that the reinforced concrete material for heavily exposed structures in the infrastructure sector must be replaced by a more efficient material and its construction method. In materials research in the 21st century, the UHPC (ultra high performance concrete) has become the preferred option for constructive use in bridge construction and, when used appropriately, offers many possibilities

The UHPC combines the advantages of concrete construction with those of steel construction and is also more durable. The main focus is on the structural detailing and application of UHPC prefabricated parts appropriate to the material and the associated reduction in susceptibility to corrosion, the main disadvantage of concrete bridges.

The use of UHPC-bridgefamilyIntegral in bridge construction should, in addition to a possible longer service life, primarily enable resource savings and the associated savings in CO2 consumption compared to reinforced concrete construction. For an example of 170m long span bridge structure, the article shows a comparison between the reinforced concrete construction and the UHPC construction, both in terms of mass and energy consumption.

The structural optimization of the flat UHPC side wall is done on the one hand by adapting the panel thickness and by making targeted openings. In the following, some of the construction-specific details are presented, such as the fixture and the joint detail for decoupling the roadway plate and the longitudinal structure. The presented construction of the UHPC-bridgefamilyIntegral is intended on the one hand to show the optimization possibilities for girder bridges in the medium span range and on the other hand the advantages of UHPC in terms of sustainability and resource efficiency as well as the possibilities of an aesthetic formulation for future applications.
Control and optimization of UAV measurement parameters for alignment measurement in bridge construction
Authors: Shi Xuefei , Xu Qi , Ma Haiying , Song Jun
Published: October 2021

Alignment measurement is necessary during the process of bridge construction. However, traditional measurement methods consume a lot of time and labor, especially for long-distance measurement. UAV photogrammetry has the advantages of high manoeuvrability, low cost, and independence on labour. The application of UAV to bridge alignment measurement can improve efficiency and promote construction control automation. In this paper, the framework and control parameters of UAV photogrammetry was studied. Experimental study was conducted to investigate the effect of parameters on the measurement accuracy including flying height, angle of bundle, camera position and photo quantity. On this basis, the optimal parameters for bridge alignment photogrammetry are summarized. With the optimized measurement scheme, the coordinate measurement accuracy of each point can reach millimetre level.
Durability design of composite bridges with given life in seasonal freezing region
Authors: Shi Xuefei , Xu Qi , Ma Haiying , Liu Jian
Published: October 2021

Steel-concrete composite bridges are currently widely used in highway bridges in China. To reduce durability problems in seasonal freezing region, a design method with given service life is used. The service life is given on the basis of the environment condition and design requirements; then the structural design and safety analysis are carried out, and the durability design and analysis of the structural components are conducted. With the consideration of the mechanical performance, construction convenience and life-cycle cost, the structural scheme for bridges using twin-I girders, cross beams and precast full-width deck is recommended. Weather resistant steel is recommended to be used in nonmarine seasonal freezing regions with stabilization treatment, waterproof and drainage design, local anti-corrosion coating. Finally, a design process considering material, protective layer thickness and construction control is proposed to improve concrete deck durability.
Exploitation problems with particular road and railway composite bridges in Bulgaria
Authors: Georgiev Lazar , Ivanov Stoyan
Published: October 2021

Composite steel-concrete bridges are having wide implementation in the present bridge practice due to their advantages. On the other hand, composite bridges have complex time dependent behaviour due to long term processes in concrete – creep and shrinkage. Stress strain state is a function of the sequence of their construction. In general, building an effective composite bridge needs relatively higher level of knowledge, precision and responsibility from designers, contractors, and relevant authorities. Implementation of composite bridge superstructures in Bulgaria is discussed in this paper. The influence of some problems related with design and construction of particular road and railway bridges on their behaviour during exploitation are analysed. Exploitation problems of three bridges are discussed. Conclusions for reasons leading to these problems and variants for avoiding them in future projects are analysed.
Addressing society’s various needs in the selection and use of key bridge components
Authors: Meng Niculin , Moor Gianni , Fanselow Michael
Published: October 2021

Key bridge components – taken here to include bearings, expansion joints, dampers, shock transmission units, seismic isolators and structural health monitoring (SHM) systems, in particular – play a key role in addressing one of society’s greatest needs: facilitating transportation where obstacles exist, by enabling bridges to function safely and efficiently. But society has further needs that must not be neglected in the selection and use of such components – most significantly in relation to their maintenance throughout their service lives and their replacement when this becomes necessary (from traffic disruption and environmental perspectives in particular), but also with respect to issues such as noise and comfort. This topic, and a number of examples indicating the wide range of possible solutions to the challenges presented, are discussed.
City of Ghent – adapting infrastructure to societal needs
Authors: Coene Renaat , Thielemans Jonas
Published: October 2021

Ghent has a history of building infrastructure for transport and mobility. In the first chapter, an overview of this history and the accompanying societal needs is presented. Next, this continuing story is set to the present day, where focus lies on sustainable means of transport. The last chapter gives an insight into what we believe to be the challenges for infrastructure in the coming years, and how this is already tangible in present-day projects.
The impact of heavy vehicle platoons on bridge traffic loads
Authors: Sjaarda Matthew , Nussbaumer Alain
Published: October 2021

Traffic experts expect that interconnected autonomous vehicles will be implemented on roads in the near future to reduce emissions and to increase safety on roads [1], [2]. Since the navigation of vehicles in platoons is highly time synchronized, current inter-vehicle distances will decrease. Simulations have been conducted to measure the effect of platoons on bridge traffic loads in this study. Information regarding vehicle characteristics in current traffic is gathered using weigh-in- motion (WIM) technology so that synthetic traffic may be generated. Platoons are created through a “swapping” algorithm; the result is a traffic stream with platoons, and an otherwise equivalent basic traffic stream. A library of bridge influence lines is then subjected to each traffic stream to observe the effects of platoons on maximum load effects. The goal is to provide policy-makers and bridge authorities with the knowledge to make wise decisions during this transportation revolution.
Eldvatn bridge – Iceland´s first network arch bridge
Authors: Óskarsson Kristján Uni , Arason Magnús , Einarsson Baldvin , Valur Guðmundsson Guðmundur
Published: October 2021

Following an enormous flooding event in the Skaftá glacial river in the south of Iceland in 2015, which severely damaged the existing bridge, a new network arch bridge has been designed, constructed and opened in 2019 to restore a much-needed road connection across the river adjoining the Main Ring Road [1]. The 79 m long bridge, designed by EFLA in cooperation with the Icelandic Road and Coastal Administration, is the first network arch bridge in Iceland.
Framework for investigating the effect of different design lives on the design of bridges
Authors: Svechnikov Egor , Maljaars Johan , Snijder Bert , de Boon Johan , Drenth Eize
Published: October 2021

Many developed countries have a national road network including a significant number of bridges in need of renovation or replacement in the coming years. The reason for this is their technical and functional capacity becoming insufficient due to aging and changes in societal demands. Therefore, these bridges need to be adjusted or replaced. National authorities in The Netherlands currently require a design life of 100 years for new bridges, however nowadays it seems reasonable to have a certain flexibility for this parameter. Since the selected design life has its implications on structural solutions and choice of materials, the identification of the optimal design life for bridges seems necessary. This paper gives a summary on the issue regarding the optimum design life of bridges and it highlights the framework of the upcoming research activities.
Development of a traffic load model for bridge structures within an urban subway system
Authors: Tepho Thibault , Nowak Marcel , Fischer Oliver , Tamm Philipp , Schöning Markus
Published: October 2021

Subway systems are a key component of today’s urban infrastructure. However, current engineering standards such as the Eurocode only give few indications regarding the modelling of traffic loads for subway trains. For this reason, a traffic load model is developed based on load model LM71 from Eurocode 1 - Part 2, the standard load model for rail bridges. The aim is to scale this load model so that it is able to cover the extreme load effects resulting from actual subway trains within the subway network. Within the scope of these investigations, different structural systems and load effects are studied, as well as different strategies for modifying LM71 and its scaling factor α. Additionally, the results obtained for simplified beam systems are validated on real structures to account for effects like two-dimensional bearing capacity for the determination of the scaling factor α. These investigations are performed for the subway system of the city of Munich.
Updating bridge axle loads using WIM in Switzerland
Authors: Sjaarda Matthew , Nussbaumer Alain , Papastergiou Dimitrios
Published: October 2021

The Eurocode LM1 for traffic loads on bridges features side-by-side tandem axles, as well as uniformly distributed lane loads. This LM is mirrored in the Swiss code SIA 261, for new structures, as well as SIA 269, for existing structures, where updating is permitted based on existing traffic in the form of updated alpha factors, αQ1 and αQ2. The research herein uses an extensive WIM database to update alpha factors for Swiss traffic. For the first (slow) lane, this is done using simple block maxima of tandem axle statistics (daily, weekly, and yearly block maxima results are compared) with log-normal fitting to the extreme value statistic. For the second lane, a novel approach is used which reconstructs real multiple-presence scenarios from the WIM data to predict the total joint load across both lanes. The result of the single lane and joint analyses are recommended updated alpha factors reduced by a factor of one third as compared to those mandated for new construction.
Elaboration of a rapid assessment method for masonry arches
Authors: Haslbeck Matthias , Vallée Hendrik , Braml Thomas
Published: October 2021

Reassessment of masonry arches necessitates feasible methods for analysing the static behaviour of the persisting structure. In this paper, a method is presented that gives an approximation of the load bearing capacity using only very few geometrical dimensions. Unlike other commercial software kits, the methodology is not tailored to do an exact structural analysis using as-built drawings and documentations, but it is made for a rapid classification of civil engineering structures in the field. Characteristics of the proposed methodology are the analysis using thrust lines and the minimized time consumption for the exploration of the structural properties, which makes the approach the first choice for rapid classification tasks within the German Armed Forces. The application that will be delivered as an App for tablets and other mobile devices shall be used for rapid classification of masonry arches with regard to the crossing of military vehicles, but can easily be adapted for civil applications. For a worked example on the presented methodology, see [25].
Resistance of prestressed bridge girders to diagonal tension cracking
Authors: Roosen Marco A. , Hendriks Max A. N. , Yang Yuguang , van der Veen Cor , Schaafsma Dick
Published: October 2021

Diagonal tension cracking is the governing failure mode for bridge girders with a thin web that are highly prestressed and contain little shear reinforcement. When assessing existing bridge girders using the Eurocode 2 [1], it often turns out that it is not possible to demonstrate sufficient resistance to diagonal tension cracking. This paper evaluates the method to determine the maximum principal tensile stresses as used in the Eurocode 2 [1] and investigates how flexural cracks affect the principle tensile stresses in the regions without flexural cracks. This paper also investigates how the tensile strength of the web is affected by the presence of compressive stresses and by the size of the area subjected to high tensile stresses. Based on the results of these investigations, an improved model is proposed to determine the resistance to diagonal tension cracking.
Optimization in a realistic structural engineering context: redesign of the Market Hall in Ghent
Authors: Dillen Wouter , Lombaert Geert , Mertens Ruben , Van Beurden Hanne , Jaspaert Dirk
Published: October 2021

Numerical optimization has a large potential in the context of structural design, but practical applications remain scarce. Even metaheuristic algorithms, which are easy to use, are rarely adopted in practice. Possible explanations are the fact that for problems with many design variables, metaheuristic algorithms converge slowly, and that structural optimization often leads to very complex structures, resulting in a high construction cost. The aim of this paper is to illustrate the potential of numerical optimization in a realistic design context. The focus is on the steel structure of the Ghent Market Hall, which is redesigned using a genetic algorithm. The structural member groups from the original design are maintained, such that the number of design variables is sufficiently low, and that the complexity of the design remains limited. Using this approach, a design is obtained that consumes 15 % less material than the original design.
Application potential of textile reinforcement in concrete construction for infrastructure buildings: environmental performance and availability
Authors: Reichenbach Sara , Kromoser Benjamin , Preinstorfer Philipp , Huber Tobias
Published: October 2021

With the building industry being one of the main sources of carbon dioxide emission worldwide and concrete being the main construction material, new strategies have to be developed to reduce the carbon footprint thereof. The use of high-performance materials in structural concrete, as for example textile-reinforced concrete (TRC), seems to allow for a reduction of the resource consumption and the carbon emissions. The present paper addresses potential applications of TRC examining the global warming potential (GWP) of a rail platform barrier. The resource consumption is depicted in a parametrical study in terms of the necessary component height and reinforcement area considering both the serviceability limit state (SLS) as well as the ultimate limit state (ULS). The results clearly indicate an achievable reduction of the GWP during construction when using textile reinforcement made of high-performance fibres. Furthermore, an analysis of the European market was conducted to prove the availability of this new reinforcement type.
Large-scale load carrying capacity test of curved steel box girders with/without horizontal stiffeners subjected to bending
Authors: Adachi Junichi , Yamaguchi Takashi , Arai Shintaro , Takao Michiaki
Published: October 2021

Due to the girder curvature, automatic welding robots cannot be applied to welding of horizontal stiffeners to the girder web in the fabrication of curved steel box girder bridges, which increases the manufacturing costs. Therefore, elimination or reduction of the number of horizontal stiffeners without increasing the web thickness is desirable. In the present study, ultimate load carrying capacity test has been carried out and the failure process was verified in order to evaluate the mechanical effects of horizontal stiffeners on the ultimate load carrying capacity. From the experimental results, it was found that, even in case the horizontal stiffeners are eliminated, the ultimate load carrying capacity decrease is much smaller than the decrease of the bending buckling strength of the web panel specified in the general design code. Furthermore, it was concluded that the compression flange of box girders restrains bending buckling of the web panel.
Parametric bridge design – reinforcement design
Authors: Navrátil Jaroslav , Ševčík Petr , Stampler Johann , Strekelj Gregor
Published: October 2021

Using BIM technology for the design process in the construction industry has become somewhat of a standard approach. For bridge design, various solutions offering geometric design functionality and data management facilities are available on the market. However, integrated solutions for seamlessly supporting the whole planning process are still a scarce commodity. The solution presented integrates architectural modeling, structural analysis, and sophisticated proof checking functionality in one package, where, based on a 4D architectural model, an analysis model is automatically derived, allowing for simulating the erection process in detail and investigating all relevant stress states. The focus of the paper is the reinforcement design of prestressed concrete sections, which is one of the most challenging tasks among the various requirements arising in the design process.
Parametric study of orthotropic steel decks with open ribs using FEA
Authors: Fang Heng , Van Staen Gilles , De Backer Hans
Published: October 2021

For orthotropic steel deck (OSD) bridges, the open ribs are less used because of their relatively lower torsional stiffness. However, with the design focus of OSD shifts from strength design to fatigue design, the system of open ribs shows the potential to be more considered for future projects. In this paper, a newly built OSD bridge is investigated focusing on the rib-to-crossbeam joint. Based on the in-situ measurements of the existing bridge, the numerical modeling of the whole bridge is finished. Furthermore, a simplified local model is developed focusing on the rib-to-crossbeam joint. Then, the influences of design parameters i.e. the crossbeam span and the spacing between ribs are investigated. Research results reveal that the global behavior of the bridge can be modeled. However, calculation results of points close to the connecting weld and the cope hole do not fit well with the measurements. In this case, increasing the crossbeam span will decrease the stresses of points close to the weld toe of the connecting weld. Increasing the spacing between ribs is more effective to reduce the tangent stress around the cope hole. The most unfavorable load position does not change with these two parameters.
Analysis for optimization of spiral reinforcement in pre-fabricated bridge columns
Authors: Rehounek Lubos , Cervenka Jan , Pukl Radomír
Published: October 2021

Savings and optimization in the use of steel and concrete can significantly contribute to the reduction of CO2 emission and energy consumption, promoting a greener environment for the place we live. It has been shown that the use of multi-spiral reinforcement (MSR) in square or rectangular columns can significantly save the amount of steel for transverse reinforcement and yet can still achieve a higher structural performance than conventional tie reinforcement. The paper presents a validation of a numerical model for nonlinear analysis of novel multi-spiral reinforcement in prefabricated columns. The validated model will be used for the subsequent studies and optimization of the spiral reinforcement location, diameter and pitch. Selected arrangements of the multi-spiral reinforcements have been analysed to demonstrate their effectiveness in static and cyclic response.
A multi-objective genetic algorithm for optimal design of cable networks with external dampers and cross-ties
Authors: Di Fangdian , Chen Lin , Sun Limin
Published: October 2021

A hybrid technique combining cross-ties and external dampers has been successfully applied in several cable-stayed bridges. However, there is a lack of optimization design method in practical design of the hybrid system. Therefore, this study proposes an optimal design method to optimize the parameters of the cross-ties and external dampers for the cable vibration mitigation, using multi-objective genetic algorithm (MOGA). A two-cable hybrid system is studied in this paper and its characteristic equation is derived by using the complex modal analysis method. The optimal design method is introduced and its feasibility is demonstrated by analyzing a simple cable-damper system. Subsequently, the proposed method is used for optimal design of the cross-tie and external dampers of a two-cable hybrid system. The results indicate that the proposed method can be used for performance optimization of hybrid cable networks system in practice.
Design and analysis of the Wing-spread Bridge: a pedestrian bridge in the Binjiang Avenue, Shanghai
Authors: Luo Lanxin , Wang Ao , Liu Zhanhang , Xia Ye , Sun Limin
Published: October 2021

Along Binjiang Avenue, the landscape in Shanghai, China, a footbridge is needed to connect the two sides of the Qiantanyoucheng park. In this paper, the "Wing-spread Bridge" is designed and analyzed based on the environment and human requirements. The initial inspiration for this bridge comes from the stress ribbon structure. In the Wing-spread Bridge's structural design, the stress ribbon and arch are combined to reduce both components' horizontal force. Meanwhile, abutment, arch foot, and bridge tower are combined as one tower, and this tower is shaped like a dove according to the surrounding natural conditions. The combination and adjustment of the components make the structure beautiful and competitive in the landscape. Finally, this bridge's FE model is established, and the static is carried out based on it. The results show that the bridge can meet the specification requirements in static aspects.
Multi-level objective optimization method for high rise frame shear wall structure
Authors: Yao Jie , Zhao Xin
Published: October 2021

Automatic optimum design is the future development trend of structural design. The main purpose of this study is to propose an automatic optimum design method for building structures. Based on the Bidirectional Evolutionary Structural Optimization(BESO) method, this paper introduces the concept of multi-level objective, and proposes Multi-level objective Optimization Method(MLOOM). By reducing the constraint redundancy of structural members, this method can reduce the structural cost as much as possible and allocate the structural materials reasonably. MLOOM is close to the practical engineering experience, and improves the efficiency and effect of optimization based traditional algorithm. Taking two story and ten story steel frame shear wall structure as examples, the efficiency and economy of the optimization method are illustrated.
Correlation between the rust colour distribution rate and corroded surface characteristics of galvanized steel wires
Authors: Miyachi Kazuhiro , Kajita Atsuto
Published: October 2021

This study investigated the correlation of the rust colour distribution rate provided by using a digital image colour analysis system and the corroded surface characteristics provided by using a non- contact surface mapping technique. The ratio of zinc-specific white rust to iron-specific red rust, which characterizes the corrosion status of bridge wires, can be quantified by introducing the digital image colour analysis system. Regarding the correlation between the rust colour distribution rate and the corrosion surface characteristics, it was found that the corrosion loss rate and the pit depth increase as the white rust rate decreases.
Evaluation method of defects in concrete structures using hammer test by time-frequency analysis and neural networks
Authors: Fan Shushu , Takeya Kouichi , Sasaki Eiichi
Published: October 2021

The hammer test is generally used as one of the non-destructive methods for detecting defects such as voids and delamination in concrete structures like tunnels and bridges. It is necessary to eliminate human mistakes and improve quantitative analysis so that Impact Acoustics Method (IAM) was proposed and studied. IAM helps human decision of the defective concrete parts through comparing waveform and frequency distribution between healthy and defective parts which are taken from sensor or microphone. Hence, artificial intelligence (AI) is expected to replace or assist the human labor inspection by quantifying the defects. This research aims to inspect defects quickly and efficiently the only microphone through promoting a machine learning AI analysis system flow which mainly includes neural networks. Two experiments were held to achieve the purpose.
Fatigue assessment of a steel truss bridge based on multi-dimensional finite element modelling
Authors: Hectors Kris , De Backer Hans , Saelens Lien , De Waele Wim
Published: October 2021

This paper presents a multidimensional finite element modelling approach for the fatigue assessment of welded railway bridges based on a case study of a railway bridge in Belgium. The nominal stress approach of Eurocode 3 is compared to a hot spot stress based fatigue life calculation for the standardized fatigue load models for railway traffic. Hot spot stresses are calculated with an in-house developed framework that allows automated determination of hot spot stresses. It is discussed how this work can fit in a larger decision support system in the scope of structural health monitoring. The presented approach proves to be better for decision support compared to the conventional approach in the Eurocode.
Non-destructive and effective bridge monitoring through fast-falling weight deflectometer
Authors: Puppio Mario Lucio , Mistretta Fausto , Coni Mauro , Sassu Mauro
Published: October 2021

Recent collapses due to hydrogeological soil instability caused by extreme climate events recall the attention on a large-scale monitoring of the road infrastructures, particularly bridges and viaducts. Several studies focus the attention on both hydraulic and structural issues. In-depth systematic investigations do not suit this purpose because of time and cost investments usually carried out from local authorities. Increasing needs of available fast, low cost and reliable methods to investigate the performance of the road and bridges pushed towards new applications. The use of Fast-Falling Weight Deflectometer, conceived for airport pavements, is here applied as a non-destructive test to evaluate the stiffness of the deck and embankment of a bridge. The- Fast Falling Weight Deflectometer can produce a broadband, constant and replicable dynamic force, providing data in real time. An experimental campaign is here described on a case study of single span bridge.
Standardised bridge weigh-in-motion data and its applications in bridge engineering
Authors: Qvisen Jami , Lin Weiwei , Lilja Heikki , Tirkkonen Timo , Peltomaa Mikko , Jussila Antti
Published: October 2021

Applying actual traffic data in bridge analyses will provide more accurate results compared to the results obtained according to the Eurocode traffic load models. Bridge Weigh-in-Motion (B-WIM) measurements are an excellent tool to produce such data. Using B-WIM data as a part of the bridge design or assessment processes has a large potential, but the lack of widely adopted standardised data format hinders broader utilisation of it. This study proposes a new standardised format to present the measured B-WIM data so that in the future, developed software can directly utilise any available B-WIM data. This would make calculations with multiple different traffic compositions and types straightforward and enable the basis for further utilisation of B-WIM data in bridge design/assessment. To demonstrate the benefits, a fatigue case study of an orthotropic bridge deck was conducted, and the results were compared to ones obtained according to Eurocode FLM 4.
Multidimensional load-bearing behaviour of timber-concrete composite road bridges with consideration of flexibility of connections
Authors: Dreifke Paul , Göckel Tim , Laubach Andreas , Schaffitzel‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌ Jürgen
Published: October 2021

Timber-concrete-composite structures for road bridges could be much more often used in the field of medium-span road bridges due to their good ecological and structural performance. Therefore, an appropriate consideration of the punctual connections usually used for such bridges is necessary. Those connectors have a large load-bearing capacity and stiffness. While there are established methods for determining the stiffness and load-bearing capacity in the main longitudinal load- bearing direction, the secondary load-bearing behaviour in transverse and vertical direction is usually not determined for those bridges. By assessing test results and evaluation of FE simulations, this article presents an approach of how a calculation method can be derived that makes the structural design of timber-concrete-composite bridges safely even in more demanding application scenarios.
Butt welded connections of high strength steel
Authors: von Arnim Mareike , Spiegler Jennifer , Kuhlmann Ulrike
Published: October 2021

High-performance materials such as high strength steels allow for resource-efficient innovative structures. Therefore, economical and user-friendly design concepts for welded connections of high strength steels are required. Current design rules had been developed mainly for mild steels, e.g. requiring an overmatching of the filler metal. It is not considered, that a soft area which may form in the heat-affected zone of welded high strength steel connections may lead to an overestimation of the load-carrying capacity. Besides, mixed connections as well as under- and overmatching filler metals are not included in the current design codes. Based on a large number of experimental and numerical investigations, a design concept has been developed which takes the characteristics of butt welded high strength steel connections into account. Additionally, experimental and numerical investigations are planned to transfer the new concept of design also to mixed connections.
Timber-granite-composite structures for pedestrian and cycle path bridges
Authors: Walgenbach-Albat Florian , Göckel Tim , Laubach Andreas , Kusser Georg , Miebach Frank , Schaffitzel Jürgen
Published: October 2021

This paper presents intermediate results of a cooperative research team on feasible shear- connections for timber-granite-composite structures for pedestrian and cycle path bridges. At the beginning, feasible shear-connector concepts are presented, which are analysed in a first shear test series with regard to load-bearing capacity, stiffness, fracture behaviour, and also manufacturability and economic efficiency. Based on the shear tests, a connector is finally selected which can be used in timber-granite-composite structures and will be further investigated in the progressing research project.
Innovative TBM traffic tunnels
Authors: Pompeu-Santos Silvino
Published: October 2021

TBM tunnels, ie. tunnels made with the TBM ("Tunnel Boring Machine") technique are currently the most common in the construction of traffic infrastructure, allowing a significant reduction in costs, environmental impact and construction time. However, TBM traffic tunnels still face important challenges.

In order to overcome these challenges, innovative concepts were recently developed by the author: the TISB ("Tunnel of Improved Seismic Behaviour") concept, which allows the reliable construction of TBM tunnels on soft ground in seismic areas, and the TMG ("Tunnel Multi Gallery") and the TMF ("Tunnel Multi Floor") concepts, for rail and road tunnels respectively, allow to obtain very economical tunnels, while significantly improving safety of users during operation.

In the paper the description and justification of these new concepts are presented, as well as their application to TBM railway and road tunnels.
Reliability, sustainability and innovation in bridges and structures
Authors: Reis Antonio J. , Oliveira Pedro José J.
Published: October 2021

Structural engineers should develop new concepts for reliable structures taking into consideration sensitivity to sustainability and aesthetics as social requirements. New ideas, as part of a creative process, is a social responsibility for structural engineers. Innovative structural designs seek to answer to new challenges from architectural developments, plastic arts, and social needs.

Some “old ideas with a new twist” for new trends in bridge design are discussed. New materials (like HSS), new architecture challenges and new geometrical shapes (at structure or at cross section levels) are highlighted. Design and structural analysis issues, imposed by what may be considered as innovations, are discussed towards future social needs.
Footbridge Nelson Mandela in Béziers: a contemporary slender arch bridge in UHPFRC
Authors: Peigneux Christophe , Servais Vincent
Published: October 2021

This paper presents an innovative footbridge consisting in an arch in UHPFRC with filling in expanded clay grains crushed and spandrel walls in gabion. The analysis of Béziers’ architectural heritage leads to propose an innovative design concept: build a bridge without any dilatation joint and bearing, resort to a millenary technology but adapt it to a contemporary material, the Ultra-High- Performance Fibre-Reinforced Concrete (UHPFRC). The repetitive use of similar elements in the arch allows minimising the incidence of formwork complexity and consequently, allows respecting the maximum overall costs. The footbridge has a main span around 36 m and a 3,5 m effective width.
The Samuel De Champlain Bridge – A holistic approach to sustainability and durability
Authors: Nader Marwan , Choi Carol , Duxbury James , Mailhot Guy
Published: October 2021

The Samuel De Champlain Bridge is one of the busiest bridges in North America. With over $20 billion Canada-US trade crossings annually, it is vital to Canada’s international trade partnership.

Spanning the St. Lawrence River in Montreal, this lifeline structure faces unique hazards including extreme cold climate conditions, ice abrasion, ice-accretion on stays, de-icing salt attacks, wind, vessel collision, scour, and seismic activity, while meeting the required design life of 125 years.

This paper discusses the holistic approach adopted to achieve the project’s sustainability and durability objectives. The project started with extensive environmental assessments, implemented design strategies to minimize environmental impacts, and employed a comprehensive durability plan and a structural maintenance plan. The Samuel De Champlain Bridge received the PLATINUM ENVISION® award for Sustainable Infrastructure Project.
New concept of high voltage overhead line between Avelin and Gavrelle – structural and dynamic design
Authors: Flock Julian , de Ville de Goyet Vincent , Warnotte Viviane , Giacchetta Stephane , Havelange Charles
Published: October 2021

This paper considers a project of a new high voltage line for which the insulator chain supporting the high voltage cables is designed to remind the sail of a boat changing shape as the wind blows. Such a design with moving parts in the structure reveals new engineering challenges on how to ensure structural integrity while respecting architectural wishes. This paper presents the main structural issues of this design and how modern calculation methods allow to tackle them and prevent them.
Interaction of normal and shear loads in carbon reinforced slab segments
Authors: Becks Henrik , Bielak Jan , Hegger Josef
Published: October 2021

In recent years, textile reinforced concrete (TRC) has become increasingly important in scientific research. Thin slab segments of TRC in particular show great potential for use in secondary structural systems in bridges or high-rise buildings. However, research has not yet sufficiently investigated all load combinations and some questions remain unanswered in the design process. Especially in restrained structures the interaction of moment, shear, and normal tensile forces might govern the design. To investigate this load combination, a new test setup was developed at the Institute of Structural Concrete of the RWTH Aachen University. A numerical study complements the investigation to extend the database beyond the limited range of experimentally tested parameters. According to the results, the shear resistance decreases with increasing tensile normal force, yet separation cracks have no negative influence.
Gaining a realistic fatigue load model using sensor-based measurements
Authors: Schaller Melanie , Pelke Eberhard , Gallo Christoph
Published: October 2021

In this article, fatigue calculations based on the modified fatigue load model 4 (ELM 4) of the recalculation guideline of BASt are compared with an object-specific calculation of sensor-based measurements, using the Lichfield Bridge in Limburg an der Lahn as an example. A central part of this contribution consists of the presentation of the data evaluation, with the help of which a weight distribution and the traffic composition of the five standard trucks of the modified ELM 4 could be evaluated. Another focus lies on the evaluation of the economic consequences of these modified damage calculations.
Equivalent nosing force for a steel railway bridge based on in situ measurements
Authors: Georgiev Lazar , Zdravkov Lyubomir , Tanev Vatyu , Lepoev Milcho
Published: October 2021

The weight and design speed of the railway vehicles increases in time. As a result, the values of design loads grow up. In old Bulgarian standard [1] the equivalent nosing force is prescribed as 60kN. In the present EN1991-2 [2] this value is 100kN. Meanwhile, a significant part of the very old bridges is not designed for nosing forces. In cases of long span between cross girders of the “open type” deck and lack of nosing braces, the load bearing capacity of longitudinal girders, concerning out of plane bending moments due to nosing forces, is insufficient. To investigate the value of equivalent nosing force are provided “in situ” measurements on the longitudinal girders of “open type” deck of a steel riveted railway bridge in exploitation in the Republic of Bulgaria. The strains and horizontal linear deformations are measured in the midspan of the longitudinal beams for real trains. The equivalent nosing force is calculated using developed procedures.
Fixed link crossings: a global perspective
Authors: Collings David , Mullins Paul
Published: October 2021

This paper benchmarks the challenges involved with major sea, or fixed link, crossings from their planning to final construction. Initially it gives an overview of existing major crossings globally, including statistical information such as length and inflation adjusted project costs. Well known links such as the UK Channel Tunnel and the more recent Hong Kong Zhuhai Macau crossing have been included in the data. The paper considers the construction methods required to surmount the challenges of bridging or tunnelling such crossings. The paper presents statistics on the construction time period for these crossings and considers links between construction time and cost. Finally, the paper looks to the future: How the data can be used to better bound estimates of time and costs for fixed link projects. The paper also considers other potentially important future benchmarking data such as carbon emissions.
Verification calculation of the Cortenoeverse bridge using finite element analysis
Authors: Dai Y. , Riemens K. W.
Published: October 2021

The Cortenoeverse bridge is a multi-span pre-stressed concrete box girder bridge near Zutphen, the Netherlands. Following the discovery of certain damages at the sides of the bridge where post- tensioned tendons are stressed, several repairs have already taken place. The Dutch agency Rijkswaterstaat (RWS) still deemed it desirable to further investigate the structural safety and usability of the whole bridge during the residual service life. Subsequently. ABT was commissioned to perform a verification calculation. Finite element analysis (FEA) was applied to analyse the structural behaviour of the bridge. Compared to analytical methods, FEA can simulate the occurring forces more accurately and give more insights into the structural behaviour of the bridge. The bridge was modelled using 2.5D curved shell elements with embedded reinforcements subjected to post- tensioning loads. An overview is given for the FEM model, the calculation procedure and the results.
Challenges when enhancing the infrastructure – case studies
Authors: Hertle Robert , Hertle Thomas , Brehm Eric
Published: October 2021

The fundamental rational of the German way to ensure structural safety and to prevent the society from undue harm is independent design review and execution supervision. This paper will explain both regarding the way in which review and supervision are performed, as well as the qualification needed for the design and supervision review engineer, who acts as a trustee of the public administration. The development of the review and supervision regime and of the underlying set of technical rules and regulations will be addressed by discussing actual and historic case studies. Special emphasis will be put on the interface-problems when different parties are involved and on the necessity of good and reliable coordination mechanisms between the involved parties. As a consequence of the increasing fragmentation of the design process in combination with the use of complex software tools and inevitable time pressure often the integrated design review process is the last line of defence to avoid incidents due to minor lapses or serious misjudgements.
Fire behaviour of large scale loaded tunnel segment tests for project Rotterdamsebaan, The Netherlands
Authors: Parwani Kamakshi , Bienefelt Jos , Rakovec Tomas , Haring Frank
Published: October 2021

Assessing the performance of tunnels in fire is becoming increasingly crucial for the overall usability and durability of the structure. One of the most reliable methods for evaluating the presentation of the concrete during fire in tunnels is by testing. In this work, the fire tests performed on the Victory Boogie Woogietunnel, project Rotterdamsebaan (The Hague, the Netherlands) are discussed. The study aims to assess the fire performance of the cut and cover concrete section when subjected to a tunnel fire curve. A series of 6 fire tests were performed on concrete slabs of the size 5,0 m x 2,4 m x 0,4 m when exposed to Rijkswaterstaat (RWS) fire curve for 120 minutes. Based on the work, one of the main conclusions drawn were that it is necessary to test a large-scale specimen to judge the performance of a protection system accurately. Another important conclusion is that the test specimen should have the concrete mixture which accurately represents the tunnel concrete to avoid uncertainty in the fire induced spalling behaviour of concrete.
Investigation of hybrid multi-core buckling-restrained brace components
Authors: Thibault Pierre , Annan Charles-Darwin , Dey Pampa
Published: October 2021

Contemporary seismic-resistant design of steel braced frames is based on dissipating seismic energy through significant inelastic axial deformation in brace components. Buckling-restrained braced (BRB) frames are a type of concentrically braced frame (CBF) characterised by braces that yield both in tension and in compression. These braces therefore exhibit superior cyclic performance compared with traditional CBFs. However, buckling-restrained braces commonly display a low post- yield stiffness, causing substantial interstory drifts and large residual drifts after seismic events. Moreover, yielding of the core is often only tied to a single performance objective, thus making its performance at other levels of seismicity largely unknown. One promising solution is the use of a hybrid BRB, where multiple cores made from different metals are connected in parallel to work together and complement each other. This research is geared towards first evaluating the potential of different combinations of core materials, followed by the design of a hybrid BRB system that can accommodate multiple core plates. Results show that the post-yield behaviour of hybrid BRBs is improved by employing a combination of 350WT carbon steel and another metal with low-yield and high strain-hardening behaviour, such as stainless steels, aluminium alloys, or other grades of carbon steels. Finally, a detailed overview of one hybrid BRB solution is proposed.