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Using 3D models in the design phase of bridges helps the engineer to verify the bridge's geometry and to analyse its aesthetic qualities. When these models are parameterized, the whole design process becomes more dynamic and standardized, which is very attractive to the infrastructure area of bridge engineering. This work presents a technique for automated generation of box girder bridge models, in which the geometric parameters are defined based on current design standards and criteria. Fast generation of a bridge's model allows the engineer to make quicker decisions about the adopted structural solution, which expedites bridge design. Two case studies are chosen to present more details and validate the proposed technique: an existing overpass located in an urban area, and a fictitious bridge connecting two coastal cities. [ABSTRACT FROM AUTHOR]

Cable supported bridges are typically part of community-critical infrastructure and therefore the consequences arising from extensive structural damage due to a fire and the subsequent operational discontinuity could be significant beyond the damage to the bridge itself and the cost of repairs. Bridge design standards generally do not provide guidance and hence fire resistance requirements are often informed by first principles assessments of the thermal and structural response of the structure to proposed fire scenarios. A deterministic assessment can provide a reasonable worst-case scenario but it does not allow bridge stakeholders to make informed decisions with regards to uncertainty and the low likelihood of fires occurring to identify the benefits of investments in structural fire protection. This is because the target reliability required for each bridge may be different depending on its characteristics, and the expected fire severity has a probabilistic nature. This research aims to fill this gap by undertaking a reliability-based analysis to assess the probability of structural failure by considering the probability of a fire of a given size occurring and the uncertainty in the incident location and wind. The methodology is demonstrated through the case study of an operational 450 m long cable supported bridge section and a fire scenario based on a liquid fuel tanker. Liquid tankers can result into two type of fire scenario: first, a fire being contained within the tanker; and secondly, a fire due to a pool on the deck. Both fire scenarios have been characterised and it was determined that the contained tanker scenario presents a more onerous design case owing to its more prolonged duration. A Monte Carlo analysis was undertaken for a total of 10,000 independent trials of the combination of the location of the fire and the wind direction. The frequency of the fire was also examined to establish the probability of structural failure of a cable. It was established that the inclusion of wind can sometimes reduce the estimated height at which cables may experience temperatures with the potential to cause cable failure. However, for a number of the cases, the estimated height can remain broadly similar (i.e. within a couple metres difference) to the worst-case calculated value. Based on this analysis, the influence of the required level of reliability as well the fire protection duration specification agreed with bridge stakeholders can be used to determine the height at which cable fire protection is necessary to reduce the probability of structural failure to a level acceptable to the stakeholders. This approach allows bridge designers and stakeholders to make informed decisions with regards to provision and extent of fire preventive/protective measures for cable supported bridges. [ABSTRACT FROM AUTHOR]

Aerodynamic stability and buffeting response due to turbulent wind have a fundamental importance for long-span bridge design. However, there are no benchmark cases that can be used as a reference estimate for an independent validation of the numerical methods and theoretical approximations. Therefore, the IABSE Task Group 3.1 proposal is to fill this gap by defining a reasonably well predicted set case for the response to wind of long-span bridges, both in terms of aerodynamic stability and buffeting. Specifically, a statistical analysis was performed on the numerical results collected by the task group participants, who used their own methodology and tools (either in time domain and/or frequency domain) to predict the bridge stability to flutter and buffeting response to wind, sharing the same input data (wind conditions, bridge structural properties, and deck aerodynamic coefficients). The benchmark results presented in this paper can be used as a point of reference for other numerical codes, and they include the onset of flutter speed, damping ratio variation with mean wind speed and the root mean square of the displacements as a function of mean wind speed, power spectral density values, and time histories of displacements. [ABSTRACT FROM AUTHOR]

The flutter stability problem is addressed based on a realistic case study, namely the Julsundet Fjord Crossing, having a main span slightly longer than 1600 m. Both the service configuration and two different construction sequences are investigated. An aerodynamically efficient closed-box stiffening girder is chosen, and the preliminary design of the structure is carried out accounting for the available global and local loads as well as for the actual project constraints. In the construction phase, the evolution of the dynamical properties of the bridge that are relevant for the flutter stability assessment is closely inspected. The flutter results reveal that a multimodal approach is mandatory for an accurate prediction of the critical wind speed for this type of bridges. Indeed, bimodal calculations lead to nonconservative flutter estimates, and the work clarifies the reason for that. Although the study is limited to a null wind angle of attack, the required high safety factor against flutter instability is just barely guaranteed in service, while it is not during construction if the common strategy of deck erection proceeding symmetrically from midspan towards the pylons is followed. [ABSTRACT FROM AUTHOR]

The construction process of Longyan Bridge was constrained by the conditions at the construction site. At the site, the operation of multiple urban arteries (one river, two railways and two highways) cannot be interrupted. Additionally, this single-pylon asymmetric cable-stayed bridge is located in a karst area. To accelerate the construction of the bridge, a swivel construction method was adopted for minimal disturbance to the traffic and environment. It was decided to launch the steel box-girder through the cast-in-situ pylon without intersecting with the traffic lines and to rotate the asymmetric superstructure by 21° via a spherical swivel system. This method allows construction preparation and implementation in the most efficient way within the available time. This paper elaborates the swivel construction of the bridge where the swivel weight is heaviest (i.e. 2.36×107 kg) in a karst area. The design method for the spherical hinge is presented as an example and validated, in which a simplified method and engineering practice are integrated. Additionally, monitoring and control measures during the rotation process and weighing test are conducted to achieve the stability and safety of the construction. Useful reference describing the swivel construction is provided that can be particularly instructive for future accelerated bridge construction. [ABSTRACT FROM AUTHOR]

This paper describes traditional strengthening methods and proposes new approaches for strengthening historical steel bridges with the use of modern materials. There is a discussion of known bridge-strengthening methods, and several new ways to strengthen bridges are proposed. The first section presents the history of steel bridges, and discusses structural materials and bridge design. Types of structures and decks used for railway and roadway traffic are mentioned. This section also describes how the materials were joined, and how they were assembled by riveting. The second section lists the flaws and defects that typically occur on historical steel bridges. Each defect is described with respect to its origin, its effect on the structure and possible consequences. This section also introduces the main points that should be investigated when inspecting a steel bridge. The third section discusses ways of strengthening steel bridges. Issues to consider when choosing the most suitable strengthening method are introduced. Traditional methods are presented, followed by modern strengthening methods. The benefits and drawbacks of each method are listed. Finally, new strengthening methods with the use of modern materials such as shape memory alloys, ultra high performance concrete and carbon-fibre-reinforced polymers are proposed. [ABSTRACT FROM AUTHOR]

Nanjing Jiangxinzhou Yangtze River Bridge is located at Nanjing, People's Republic of China. The main bridge spans Yangtze River in the form of a cable-stayed bridge with three towers and two main spans, with a total length of 1796 m and a main span of 600 m. The towers and main beams of the bridge are all steel–concrete composite structures, which is the first all-steel–concrete composite structure cable-stayed bridge in the world. The bridge innovatively develops a steel shell–concrete composite structure tower, deploys coarse aggregate reactive powder concrete (CA-RPC), and applies it to the main girder of the bridge to form a lightweight and high-performance steel–concrete composite beam. Numerous innovative technologies have been achieved with new materials, new structures, new processes, and many other aspects. The unique structural concept has significantly increased the factory manufacturing speed of bridge components, which not only reduces the work and labour cost at the bridge site above the bearing platform to less than 25% but also effectively reduces the amount and loss of engineering materials during bridge construction, all of which have made outstanding contributions to the development of cable-stayed bridges. At the same time, it has also contributed a bridge of stunning appearance and unique structure to China and world bridge engineering. [ABSTRACT FROM AUTHOR]

This paper describes the design evolution and construction steps of Gravina (or "La Martella") Bridge, on S.S. 655 "Bradanica" Road, under the authority of the ANAS Department of Potenza, Italy. The final design of the bridge adopted the original solution for a "split" bowstring arch bridge first proposed by Arenas for Barqueta Bridge in 1992. Considering the cultural, historical and environmental heritage of the Gravina prestigious site, the bowstring arch type appeared to be perfectly in line with the contest of "La Martella" bridge. The bridge was re-designed later: the "as-built" solution shows some "adjustments" that were necessary to make bridge construction easier and to improve structural durability. To this end, although the original proportions were preserved, the original "split" arch was replaced by a couple of flanked and converging tubular arches, while a simpler composite deck was used instead of the original steel "boxed-reticular-open section". [ABSTRACT FROM AUTHOR]

As the frequency of thermal extremes gradually increases owing to climate change, the role of thermal loads on bridge performance increasingly becomes a concern. The purpose of this study is to investigate the suitability of AASHTO Bridge Design Specifications in quantifying with confidence the design thermal gradients that account for cold wave events. An advanced finite element platform was used to model the thermal performance of a prestressed concrete box girder and to analyse the thermal gradients that occur during cold wave events. Meteorological data on four historical cold wave events in Ontario, Canada, were used as input in the thermal models to simulate the temperature distribution within the bridge deck. The temperature–time history distributions obtained were then used as boundary conditions in a structural finite element model to simulate the structural response. The thermal results indicate that the AASHTO recommended gradients failed to capture the true thermal load distribution within the superstructure, which led to an underestimation of the resulting structural implications. [ABSTRACT FROM AUTHOR]

Compared with traditional multi-girder bridge systems, an I-girder system using two main girders simplifies the construction process and saves material consumption and is becoming a representative system used in bridge industrialization in China. However, owing to the low torsional stiffness and poor stability of the traditional I-section, more lateral connections (diaphragms or cross-frames) and stiffeners are required to form a frame to ensure safety and structural performance during the construction process. This article proposes an innovative girder system with hollow top tubular flanges to replace the top plate of the traditional I-section with a hollow rectangular tube that improves the torsional stiffness of the traditional I-section, but the bending performance is basically unchanged. In this article, the structural performance of this innovative system is studied, and compared with the traditional I-girder system. The analysis results show that the innovative bridge system using tubular flange has better performance than the traditional I-girder system, and can be applied to industrialized bridge construction. [ABSTRACT FROM AUTHOR]

As the pedestrian bridge is in a period of rapid development, many issues such as design defects, lagging construction techniques and uncoordinated environmental boundaries have been exposed in the process of construction and maintenance. This article studies the conceptual design of the pedestrian bridge from the viewpoint of holistic engineering construction. By sorting out the developing context of existing pedestrian bridges at home and abroad, it analyzes the existing problems of pedestrian bridges and tracks their root causes. On this basis, combined with excellent international examples of pedestrian bridges, the developing trend of pedestrian bridges is summarized and fundamental design considerations for contemporary pedestrian bridges are proposed centering on the design concept, structural modeling and environmental landscape innovation. Based on design considerations for pedestrian bridges and the application of cutting-edge technologies such as new bridge materials, construction processes and innovative structures, conceptual design strategies for pedestrian bridges are approached by integrated assembling, digitizing, intelligentizing and humanizing design. The article also explores the feasibility of interdisciplinary and cross-cultural inspiration in the application of pedestrian bridge structures. This study attempts to develop a framework for integrating analytic process strategies, and the research content of this article can provide some reference for pedestrian bridge design. [ABSTRACT FROM AUTHOR]

An alternative mix design using polypropylene fiber-reinforced high early strength concrete was proposed by the Idaho Transportation Department for the longitudinal connections between deck bulb-T precast bridge girders in accelerated bridge construction. In this paper, finite element models of the pullout behavior of headed reinforcing bars in the closure pour and bending tests of beams representing a 30 cm strip of the bridge deck were developed. The smeared crack model was used for concrete, while cohesive zone modeling showed good results in representing the interface between the closure pour and precast concrete. Steel-concrete bond-slip behavior was observed to be one of the most significant factors affecting the results. A scheme to simulate this behavior using zero-length nonlinear spring elements was designed. The finite element models were able to produce results similar to the experimental findings. [ABSTRACT FROM AUTHOR]

The article announces the call for entry submissions for the annual IABSE Awards and Gala Dinner in Zurich, Switzerland. The awards aim to recognize outstanding achievements in structural engineering worldwide. The awards are divided into two categories: the IABSE People and Paper Awards and the IABSE Projects and Technology Awards. The article provides detailed information about the award categories, eligibility criteria, entry requirements, and where to submit entries for the Project and Technology Award category. The submission deadline is two years after the completion of the project. The judging criteria for the awards include sustainability, creative innovation, elegant solutions, and structural excellence. More information can be found on the IABSE Awards website. [Extracted from the article]

The Wufengshan Yangtze River Bridge, a thousand-meter scale high-speed railway suspension bridge, is located in Zhenjiang, Jiangsu Province, China. The construction of the bridge surpasses the technological limits of the thousand-meter scale railway bridge. To accomplish this feat, a new type of plate-truss steel beam was adopted for the first time, along with a full penetration welding method employed between the U-rib and the top deck. These innovative methods fill the gaps in high-speed railway suspension bridge construction technology in China and the world. This paper describes the design method, calculation theory, and the corresponding technical standards of high-speed railway suspension bridges in China, which together provide the information necessary for the construction of the subsequent bridges. [ABSTRACT FROM AUTHOR]

This paper describes the principles, analysis and capacities of the axial-deck method developed in research on the optimization of the curved bridges directrices takin place at the UPM university in Madrid. The axial-deck method focuses on the two main structural challenges of curved cable-stayed bridges: the horizontal component of the load introduced by the stay cables on the deck; and the big torsion forces in the deck due to the unbalanced cable-stayed system. Hitherto, these problems have been addressed, either by optimizing the position of the tower and its geometric characteristics, or by modifying the morphology of the stay-cable system. Very little has been written about the possibilities of linking the structural behaviour to the deck directrix. This paper starts by describing the ideal solution equations, without considering the structure as statically indeterminate. Then, based on these equations, it follows the evolution of the method to a nonlinear iterative system. This evolution allows designs to be developed that consider the flexibility relation of all the structural systems involved in the problems. Finally, the method is validated with the redesign of two existing curved pedestrian bridges from prestigious engineering firms and the paper concludes with a structural behaviour analysis of all designs. [ABSTRACT FROM AUTHOR]

This article discusses the elements for a good design, including the importance of beauty and context sensitiveness, to achieve design excellence. A good bridge is more than an economical, safe, and functional structure with an attractive appearance; it should contribute to the overall quality of its urban context or the natural landscape's beauty. A good bridge design must also embrace sustainability practices as part of collective action to reduce global warming and natural resources. No definitive guidelines to the design process exist. Therefore, bridge design is an art that uses scientific methods to solve the technical aspects. As each bridge has a specific purpose, agents, consequences and context, there are countless responses based on the engineer's knowledge, creativity and ethics. The critical idea reviewed in this article is how to improve the design practices to increase our bridges' quality and contribute to a better world. "Less and better" is to be read "do better with less", incorporating the sustainability principle of "doing more with less" and the fundamental principles to achieve design excellence in bridge design "do better". [ABSTRACT FROM AUTHOR]

The article proposes three essential elements in the bridge design process: site, type and drawing. The site defines the problem. The type relates to structural history. The study of alternatives constantly turns to the open catalogue of types for support. Drawing is the conceptual synthesis that builds on the two previous elements. Bridge design entails drawing as much as analysis and sometimes it is even more about geometry than about engineering. To design is to draw. A discussion of the proposed key design components is followed by a description of several bridges and footbridges designed by the authors: a competition proposal in the United Kingdom, two competition-winning footbridges—over the Drava river in Maribor, Slovenia, and over the Miño river between Spain and Portugal—and two urban bridges built in Riyadh. The presentation of the projects is structured according to the three essential elements proposed (site, type and drawing) and highlights the main characteristics of each project and the key aspects of their design processes. In conclusion, the article proposes several actions to be considered as open instructions or recommendations for bridge design with the aim of being both a design method and a manifesto to encourage creative structural engineering. [ABSTRACT FROM AUTHOR]

In bridge planning, the successful translation of the many conditioning factors into a solution that meets all safety requirements while also addressing considerations such as economy and elegance is essentially a matter of conceptual design. Despite the utmost importance of that stage, which in addition to an intuitive understanding of load-bearing mechanisms calls for imagination and a sense of form and beauty, creative conceptual thinking is systematically underestimated both in engineering training and everyday practice. The resulting impoverishment of the profession stems not only from growing, need-driven and hardly reversible specialisation, but also from inexorably extensive and opaque standardisation and control. The rules for ensuring robustness reflect the increasing complexity and opacity characterising structural design codes. While the practical importance of designing and building robust structures is universally acknowledged, the codes presently in place are often vague or confusing. Cross-referencing, in turn, may lead to loops around rules that, confounding engineers, are counterproductive. At the same time, however, that lack of clarity may afford opportunities for innovative solutions by building items that ensure robustness into the conceptual design of a structure. This paper proposes an operational design process that deals appropriately with all factors of structural performance, including robustness, without compromising bridge economy or elegance. That process, which combines a number of robustness strategies, including risk-based considerations, is illustrated with a case study of a proposal submitted to a design competition for a viaduct. [ABSTRACT FROM AUTHOR]

Bridges are a paradigmatic case of human transformation of nature, and their design should always aspire to improve the quality of the built world. Even in the early stages of their history, bridges transcended their mere functional role to become objects with aesthetic ambitions. Nowadays, however, the disappearance of technical calculation limitations has made possible, in the opinion of the author, to deliver the information needed to build a bridge with almost no emotional engagement in the process. Also, education at universities rarely aims for a well-rounded set of skills that allows to simultaneously master the technical challenges of bridge design, while understanding how the users and perceivers will experience them. The objective of this article is to contribute to fill this gap by trying to understand how human beings perceive and feel the world around them, what makes parts of this world attractive for them, and how this can be consciously used as a key part of the bridge design process to conceive long-lasting valuable pieces of the built environment. [ABSTRACT FROM AUTHOR]

Hålogaland Bridge in Arctic Norway has been recognized for its elegance and respectful integration within a majestic landscape. The location north of the Arctic Circle means that the bridge must sustain extreme environmental loading, and this has called for a number of innovative design solutions. Using the setting and functional requirements in a creative manner as a basis for the design process, the team of bridge engineers and architects worked actively within these constraints as a unique opportunity to obtain a distinctive and immediately recognizable design, making a difference for local society and raising the profile of a remote area. The combination of a narrow bridge deck and high pylons provided the possibility of designing structurally efficient and elegantly pointed pylons that complement the pointed peaks of the surrounding landscape and especially the neighboring peak, the "Sleeping Queen" which is an important part of local history and storytelling. This paper describes the work methods, process and design criteria adopted by the design team and how aesthetic considerations and functional requirements went hand-in-hand to produce one of the most stunning bridges in the world. [ABSTRACT FROM AUTHOR]

In the realm of bridge construction, outstanding results that convince both engineering specialists as well as the general public are mostly the outcome of intense cooperation between clients, structural engineers and often architects. Particularly in the field of densely populated areas such as inner cities, urban planners as well as future users must be involved in the decision-making process. Kienlesberg Bridge is a successful example of this, from competition to commissioning. The multi-award-winning bridge for trams, pedestrians and cyclists crosses a broad rail area of Deutsche Bahn (German railway) at Ulm's central railway station. After a competition announcement in 2011, the bridge was developed in close cooperation between architects and structural engineers and built parallel to an underlying Deutsche Bahn construction site leading to its inauguration in 2018. The competition design already referred directly to the urban development situation. The elegant wave form results naturally from the interplay between the alignment, the force flow and the severe limits on possible pillar positions due to the complex construction site. In addition to its crossing function, the bridge offers a high quality of user environment thanks to its materials, lighting and equipment concepts. This creates a new urban space in inhospitable surroundings. [ABSTRACT FROM AUTHOR]

The concept of a design process imbibing motivation from a given context dates back to ancient Greek architecture in 525 BC. The structural forms used were lintels, columns and walls and they were conscious attempts to make structures aesthetically appealing. The Roman Architectural Revolution gave rise to new structural forms like arches, domes and vaults. The invention of these structural forms culminated in sturdy aqueducts and bridges and, as they did to their other structures, the Romans decorated their bridges with embellishments. Form finding and aesthetics have always been an integral part of conceptual design, although there has been no evidence of proceduralising the process of conceptual design consciously. Even to date, conceptual design is not always taught in universities, as evidenced by countless anonymous, frequent utility structures that can be seen everywhere. Engineers like Thomas Telford, Gustave Eiffel, Jhon A. Roebling, Robert Maillart, Eugene Fressinet, Jörg Schlaich and Christian Menn are responsible for the state-of-the-art design and technology of bridges and their cultural value. David Billington called efficiency, economy and elegance common denominators for the conceptualisation of bridge design. In this article, after deliberating upon form finding and aesthetics aspects, the author has attempted to delineate the process of conceptualisation with illustrations. [ABSTRACT FROM AUTHOR]

The origin of any bridge or footbridge project arises from a need to unite two realities that are separated by an existing physical barrier. It has a beginning and an end, and the path in the air that unites them can be solved by an infinite number of solutions. In each project, starting with a blank sheet, a journey takes place that goes through a creative process, a continuous back and forth from idea to detail, from the general to the particular, in an exciting game in search of a solution, in search of beauty. This process is subtle, yet has the power to excite and move us, an apparently simple harmony, behind which lies great complexity. Everything has to converge, and the forms and nuances should be balanced in a such a way that everything appears just as it should be nothing missing, yet nothing superfluous, the perfect balance of form and function. [ABSTRACT FROM AUTHOR]

The conceptual design of bridges is a critical task with the need to assess feasible schemes, not to hinder creative work, but to avoid appealing aesthetic concepts outside feasibility constraints. Ongoing bridge failures, often during the construction of innovative designs, underscore the need to re-emphasise safety and design fundamentals when pursuing aesthetic designs. The inability to provide timely reasonable cost estimates likewise leads to later embarrassing surprises. Public confidence in the bridge engineering profession suffers. This paper is not about the numerous aids to facilitate aesthetic concept development. It attempts to promote bridge conceptual design that is amenable to control. Well-reported historic failures, focusing on pioneering bridges and novel and elegant designs, are reviewed for retrospective insight and current relevance. The repeated findings of loss of control in the design and/or construction process suggest the benefit of forward risk assessment, value engineering and constructability analysis, at concept, for both structure soundness and cost estimation, especially for major signature structures. The necessity for critical independent review is accentuated. The conceptual and aesthetic design of evolving bridges demand excellent multidisciplinary engineering capability and foresight. [ABSTRACT FROM AUTHOR]

In recent years, the requirement for landscaping has become increasingly stringent as large-scale bridge construction continues in China, and a conventional bridge scheme creation process has the disadvantage of having too many factors to consider and being difficult to coordinate and inefficient to collaborate. Faced by the current situation of short scheme creating period, bridge engineers should strengthen their role as designers and be able to perform scheme creation and design independently and efficiently. Building Information Modeling (BIM) technology can provide bridge engineers with advanced technical means and design process. This paper mainly studies how to apply BIM technology to improve the efficiency, cost control and quality of bridge scheme creation, using the Minjiang Bridge in Meishan City, Sichuan Province as an example. From the discussion it can be seen that: (1) the efficiency of scheme creation, presentation and scheme selection can be improved with the aid of the new process and approach together with the Parameterized Scheme Library; (2) the all-in-one process of scheme creation and design led by the bridge designer effectively simplifies communication and iteration; (3) compared with the conventional approach, the new method greatly improves the efficiency and quality of scheme creation. [ABSTRACT FROM AUTHOR]

The objective of a bridge design is to produce a safe bridge that satisfies all functional requirements with a cost that is acceptable by the owners. However, with accelerated development of people's aesthetic awareness, the design of urban bridges is gradually developing towards novelty, harmony, and customization. The most critical issue in constructing an aesthetically pleasing bridge is that there is no such rule to conceive of the most perfect or elegant design. In recent decades, a large number of bridges have been built on the Haihe River in Tianjin, China. This paper focuses on the introduction and implementation of innovative aesthetics design for urban bridges in this city. The design of new bridges on the Haihe River adheres to the people-oriented conception, and to the successful combination of aesthetics and functional design specifications. Complementary scientific strategies are implemented during the reconstruction of old bridges on the river to protect the cultural relics and preserve the history. The overall design conception in this paper is the harmony of mechanics and aesthetics as well as the harmony of bridges and its surrounding environment. Also, the designers and constructors follow the rules of inheriting historical emotions and human emotions. Several novel bridge cases are employed in the paper to demonstrate the design conception. [ABSTRACT FROM AUTHOR]

The first bio-based composite movable bridge has been built in Ritsumasyl, The Netherlands (Fig. 1). This paper describes the material research conducted, and takes a further look at the design of the bridge and its monitoring system. The entire bridge has an overall length of 66 m. The first half is fixed and the second consists of an asymmetrical movable swing part with a free main span of 22 m and a counterweight section of 12 m. The bridge deck is made of 85% bio-based material. In collaboration with universities, research institutes and suppliers, tests and the design of components and materials are performed. The tests are carried out in accordance with guidelines and standards, whereby the outcome is analysed and used as input parameters for the design. Due to a tight schedule for the construction of the bridge, the tests have not been scientifically analysed in detail. The project team succeeded in building a bridge from Bcomp® flax fibres, balsa and a bio-based Epoxy resin—1800 ECO + 1804 ECO made by Resoltech—which serves as an example for building the first green bridge—"green" in the sense that no synthetic chemicals and only natural fibres are used, a completely circular alternative material as one of the many possible alternative answers to tackling climate change. The bridge is equipped with an advanced monitoring system that has been built into the design. The monitoring system collects data on the behaviour of the bio-based deck for most circumstances, such as deformations, moisture content, loads and temperature. The bridge is equipped with optical fibres, with a total of 184 Fibre Bragg Grating (FBG) sensors, installed by Com&Sens. [ABSTRACT FROM AUTHOR]

Structurally this bridge was very advanced, being at its time one of the few single-cell box-girder bridges combining its large width with a long span, a tight curvature and a considerable height. The combination of the span-by-span method with the balanced cantilever method was also used by Rito on bridges where the lateral spans recommended higher span lengths, thus its deck cross-section is a box-girder along the full length. Cable-stayed Bridges Where local constraints advised medium/large to reasonably large spans or for landmark bridges, Armando Rito always tried to propose cable-stayed bridges as the best option. 17: PS031 Overpass - Portugal (2012) Rito also designed many bridges using hybrid steel and concrete solutions, either for new bridges or for the widening of existing ones. [Extracted from the article]

Until 2016, the in situ, span-by-span, prestressed concrete deck construction of multi-span bridges was limited to spans up to 78 m. This construction method, in some cases, ensures verifiable advantages in terms of construction simplicity and reduction in material consumption. After scientific and technical validation of the organic prestressing technology application in movable scaffolding systems in 2005, and evaluation of its potential features, a long-term multidisciplinary research and development project was developed to evaluate the possibility of using this technology for in situ construction of multi-span decks with spans up to 90 m. In 2018, in Turkey, the first viaduct using this technology anywhere in the world was completed. In the present paper, following a presentation of prior scientific and technological achievements, the main technical data of this case study are given, highlighting its results. This technological achievement is a contribution to the state of the art of bridge engineering and to sustainability. [ABSTRACT FROM AUTHOR]

Ji'nan Huanghe rail-cum-road bridge is a continuous steel truss girder bridge with rigid suspension stiffening chords. Considering the structural characteristics and construction conditions of the huge steel truss girder, a technique of incremental launching method with suspension cable stiffening chords was used for construction of the bridge. For the design of the support structures, assembling supports were used at the side spans and pier-side brackets were used at the central spans. During construction of the horizontal launchings, vertical jack-ups and transverse offsetting rectifying devices were arranged. The functions of the incremental launching devices and support system were qualified to realize the complicated construction work. An advanced synchronous control system was applied to implement the multi-point synchronous incremental launching. The strategy of using elastic support pads was proposed to decrease the harmful influences of the height differences of the three main trusses during construction. Using the finite element analysis, the controlling values of the height differences were determined between +15 and -25 mm to ensure the safety of the construction. The technique given in this paper could provide a reference for the construction of similar long-span bridges. [ABSTRACT FROM AUTHOR]

Three continuous bridges with typical 44 m span and different lengths (156, 288 and 614 m) have been built for the railway line from Thénia to Tizi Ouzou in the north of Algeria, which is an active seismic zone. Rail–structure interaction criteria require that railway bridges should have fix points with high horizontal stiffness. Therefore, the piers and abutments of typical railway bridges in seismic zones have very large dimensions as a consequence of huge horizontal forces generated by earthquake action in these fix points. To optimize the dimensions of the infrastructure, seismic isolation techniques using hysteretic steel devices with elastoplastic behaviour have been extensively used in these bridges, transferring controlled horizontal forces between the deck and the infrastructure. Furthermore, as a compromise between mass and cost, the bridges were designed as composite steel decks. [ABSTRACT FROM AUTHOR]

Bridges of rigid girder and flexible arch have been widely used in the construction of high-speed railways in the last several decades. This bridge type is adopted for Rongjiang Bridge in Xiamen–Shenzhen railway. The main span of Rongjiang Bridge is 220 m, and it is the longest bridge of rigid girder and flexible arch in the world at present. The main structural design criteria and details of Rongjiang Bridge are introduced in this work, and the case features of this bridge are highlighted. Besides, some key issues associated with the structural design are researched, including the mechanical property of integral gusset plate, modal analysis and dynamic response of vehicle-bridge system. The multi-scale finite element modeling technique is recommended for analysis of the complex substructures, and the operating conditions of the vehicle-bridge system can be better evaluated by the co-simulation technology of multi-body dynamics and finite element method. Finally, a brief account of the construction method of this bridge type is reviewed. [ABSTRACT FROM AUTHOR]

Ballastless track has been widely used in high-speed railway in China; however, it has not yet been laid on the high-speed railway long-span cable-stayed bridges by now. Ganjiang Bridge is a high-speed railway long-span cable-stayed bridge which is designed to lay ballastless tracks. This bridge type and parts of the local structures are first applied in the high-speed railway bridges. This study highlights the case features and structural characteristics of Ganjiang Bridge. A series of structural measures have been taken to improve the feasibility of laying ballastless tracks on the long-span cable-stayed bridges. Besides, as the critical structure of a long-span cable-stayed bridge, the new type cable-girder anchorage structure in Ganjiang Bridge is safe and reliable. Multi-scale finite element modeling technique can simply and effectively realize the accurate stress analysis of the local structures like the cable-girder anchorage region in long-span cable-stayed bridges. Finally, a brief account of the construction method of this bridge type is introduced. [ABSTRACT FROM AUTHOR]

Cable-stayed bridges are often the most economical solution for spans in the range of 150 to 500 m today and have therefore found widespread application over the past decades. In the design of cable-stayed bridges, the choice of partial factors applied on the permanent loads and the cable preload has a significant effect on economy and may even affect the feasibility of a project. While different design approaches are being used today, most designers consider the uncertainties of the two actions as correlated and hence apply the same partial factor to both actions simultaneously. However, in the frame of the development of the second generation of Eurocodes currently under way, a new code clause has recently been proposed which suggests considering different partial factors. The present paper aims to provide a basis for discussion based on the findings of a case study on three existing cable-stay bridges, where the impact of the aforementioned design approaches regarding the load factors for permanent load and cable preload was investigated. Based on the findings, recommendations for the load factors are given taking into account aspects of economy and safety. [ABSTRACT FROM AUTHOR]

A novel method for the design of variable depth single span bridges having maximum depth at the ends and minimum depth at midspan is presented. These bridges are intended to be used for long span river crossings or highway overpasses, where only a single span is required, and the vertical clearance below needs to be maximized, and/or an aesthetically pleasing graceful shape is desired. The design is made possible by "fixing" the ends to "lock-in" negative moments, so that the positive moments at midspan are greatly reduced, and a shallow section may to be used. The method is developed and presented in two parts. The first part discusses and unifies the behavior of three very famous bridges (the Luzancy Bridge in France designed by Eugène Freyssinet, the Gänstor Bridge in Germany designed by Ulrich Finsterwalder, and the Pinzano Bridge in Italy designed by Silvano Zorzi). The second part describes the method in detail by virtue of a complete design example. Application of the method to other bridges is included, and abutment treatments to enhance the visual qualities are presented. This innovative bridge type will be of interest to those looking for a practical and elegant new bridge solution for long span bridges. [ABSTRACT FROM AUTHOR]

IABSE Outstanding Structure Award Celebration for the Mukogawa Bridge Report by Akira Wada, National Group On 3 February 2020, the IABSE award celebration for the Mukogawa Bridge, which is a road bridge in Japan, was held. Sixty people attended the celebration, including Prof. Manabu Ito (Former President of IABSE), Prof. Yozo Fujino (Honorary Member of IABSE), Prof. Shunichi Nakamura (Vice-president of IABSE), Mr Toyohito Ikeda (Director-General, Road Bureau, Ministry of Land, Infrastructure, Transport and Tourism), West Nippon Expressway Company Ltd (owner), Sumitomo Mitsui Construction (designer and contractor), and bridge engineers and experts. This bridge is the first structure in the world to combine a butterfly web and an extradosed bridge. [Extracted from the article]

Past earthquakes such as the Christchurch and Kaikoura events have highlighted the difficulties in residual capacity assessment and repair of plastic hinge damage in conventional reinforced concrete bridges. Also, with growing population densities in urban centres around the world, there is substantial interest in increasing earthquake resilience and minimising the disruption caused by new bridge construction. Two areas of research that address these aspects are low damage design and accelerated bridge construction. The aims of low damage design are to significantly reduce seismically induced damage to structural members, minimise residual drifts and limit damage to specifically designed components. At the University of Canterbury, New Zealand, within the bridge engineering space over the past decade or so, particular focus has been placed on these areas of research and their combination. This paper presents an overview of the extensive experimental work undertaken at the University of Canterbury on these topics for bridges. [ABSTRACT FROM AUTHOR]

The performance assessment of four highway bridges damaged in the 2016 Kaikoura Earthquake is presented and methods adopted to repair the damage are outlined. The oldest of the four bridges was designed in 1969–70 and the newest in 2004. Although earthquake design procedures have advanced over this period, the design earthquake loadings for all four bridges were based on acceleration response spectra and the bridges detailed to have ductile failure modes in pier columns with circular sections. Levels of damage in the plastic hinges were predicted by undertaking back-analysis using static and dynamic analyses based on the ground motions recorded at strong-motion recording stations located within 1.5–7 km of the bridge sites. The response displacement of one of the bridges was considerably greater than its damage control limit state displacement. This explained the severe damage observed in the plastic hinges of this bridge. Significant plastic straining occurred in the plastic hinge reinforcement on two of the other bridges and the remaining low-cycle fatigue capacity of the column reinforcement was estimated using non-linear time history analyses. Column strengthening was required on one of these bridges and repairs without strengthening were found to be satisfactory on the other bridge. [ABSTRACT FROM AUTHOR]

Thermal actions are considered in the design of bridges, as temperature variations can lead to restraint stresses and subsequent cracking. However, load descriptions are in some cases oversimplified or incompatible with modern applications, and background studies are limited. This paper therefore aims to develop a more detailed load description for the load case describing temperature differences between structural parts in bridges, focusing on portal frame bridges. The temperature in portal frame bridges is investigated by performing long-term thermal simulations using weather data from several locations in Sweden, and thereafter performing statistical analyses of the resulting temperature variations over time. The study gives suggestions of both characteristic and quasi-permanent values to be used in design based on the statistical analyses, and also notes a gradual change in temperature between structural parts, which could be considered in the design. The resulting quasi-permanent values are significantly lower than the values given in the Eurocode for temperature differences between structural parts, which, in turn, will lead to smaller and more realistic stress values in bridge design. [ABSTRACT FROM AUTHOR]

It's like bringing owls to Athens when writing here, in our famous IABSE Journal, about design, analysis, erection and maintenance of suspension bridges. It's all known to its readers. And yet it's done, in order to shed light on the achievements of Toni Rüttimann, who together with his right-hand men and the villagers in need has built over 800 footbridges within the last 31 years in 13 countries of Latin America and Southeast Asia. And still bridge building goes on, currently in Myanmar, Indonesia and Ecuador with 40–50 bridges being built per year. [ABSTRACT FROM AUTHOR]

Worldwide, the design life of bridges can be extended by delivering repair and strengthening projects while meeting the challenge of keeping the bridge in service. Although this is a common characteristic of such international projects, there are significant differences between countries with regard to types of bridges and maintenance approaches. VSL International is active in the field of bridge repairs and strengthening in a worldwide capacity and adopts a variety of solutions to accommodate these to local conditions. This article will describe lessons learnt from a variety of projects which deal with the repair and strengthening of steel bridges, particularly cable-supported structures. Several international examples are described, in Mexico, Canada, the USA and France, where innovative solutions have been applied. These innovations focus on the unique combination of specialised temporary works, method of construction and cable technology. [ABSTRACT FROM AUTHOR]

PHOTO (COLOR): Webinar from Spain Costa Rica The recently formed Costa Rican group has been actively promoting IABSE and regularly hosting webinars. PHOTO (COLOR): South African NG Webinars Denmark On 24 February 2021, the Danish group of IABSE organised a webinar on the topic: I Køge Nord Station (TP49) - From Design Competition to Traffic Hub in Operation i . PHOTO (COLOR): Austrian NG Webinar South Africa On 9 April and 30 April 2021, the South African Group of IABSE conducted their first two webinars for IABSE. [Extracted from the article]

Highlights from the article: On 4 May 2019, the Philippine Group of IABSE celebrated IABSE's 90th anniversary by conducting an Information Forum on " I IABSE's Outstanding Structure (OStrA) Awardees and Finalists i ", with highlights on the innovations and significance of each bridge and building structure, with members and non-members. Rey Singh and Wennie Oclarino presented an overview of post-tensioning, post-tensioned flat slabs, transfer plates, post-tensioned mat foundations and prefabricated prefinished volumetric construction (PPVC) technologies to illustrate different technologies and construction schemes for high-rise buildings. In the two days of the Conference, 13 main lectures were given by prominent Brazilian and foreign specialists in the field of construction and design of bridges and other structures. Those members with particular knowledge of the bridges and some of the notable buildings on each side were available to provide commentary for those who wanted to know more about their design and construction, but as so often on these occasions it was the social and professional networking and camaraderie that proved more stimulating for most.

Highlights from the article: Young engineers need basic knowledge of structural engineering, whereas advanced engineers want to know new technologies or in-depth knowledge. Japan, China, and Korea initiated IABSE Young Engineer Colloquium in East Asia as a regional activity. PHOTO (COLOR): Fig. 9: Young Engineers Colloquium 2018 East Asia, Shunichi in front row, extreme right with participants and organisers As for IABSE activities, I would advise you to attend IABSE Congresses and Symposiums, make a presentation and share their ideas, discuss and network, join Task Groups and work together with international experts.

The old Songpu Bridge is a railway-highway combined steel truss bridge. Due to the continuously increased traffic pressure during the past decades, the Songpu Bridge needs to be widened and strengthened urgently. This paper presents key issues in the widening and reconstruction design of the old Songpu Bridge, including reinforcement of the truss, structural design of the upper and lower decks, connection details of the superstructure, transverse anti-overturning design, connecting methods between the renovated approach bridge and the old bridge and the seismic design of the renovated bridge as well. The experience and engineering practice will provide valuable references for other similar old bridges that also need retrofit and reconstruction. [ABSTRACT FROM AUTHOR]

South Africa's bridge design code, TMH7, was first introduced in 1981. In deriving the code a fully probabilistic approach was not possible due to insufficient data at the time. Various studies have shown that the code underestimates measured values in hogging, sagging and shear. A new load model, based on seven years of Weigh in Motion (WIM) data, is developed in this contribution. The Weibull distribution offers the best solution to the statistical extrapolation of load effects. A return period of 975 years is used to obtain static characteristic values for the required internal forces. As a result, the most appropriate load model for South African traffic consists of either tridem or quad axle group with an extrapolated axle weight of 160 kN and an appropriate constant UDL loading as specified in this paper. It is shown that TMH7 NA loading produces significantly smaller values than the measured WIM data for all load effects. This serves as motivation to urgently revise TMH7 loading. [ABSTRACT FROM AUTHOR]

On 14 August 2018 at 11:35 AM, a relevant portion (about 243 m) of the viaduct over the Polcevera river in Genoa collapsed, killing 43 people. The bridge was designed in the early 1960s by Riccardo Morandi, a well-known Italian engineer, and opened to the public in 1967. The collapsed part of the bridge essentially comprised an individual self-standing structure spanning 171 m and two simply-supported connecting Gerber beam systems, each spanning 36 m from the self-standing structure to the adjacent portions of the bridge. This paper aims to reminisce the complete story of the bridge, from the Italian construction boom in the 1960s to some of the issues that soon arose thereafter: the strengthening intervention in the 1990s, the subsequent structural monitoring and, finally, the strengthening project never brought to fruition. Potential reasons for the collapse are discussed, together with some of the possible inadequacies of the bridge, its maintenance and loading history based on critical reflection, comparison with specific features of bridge construction practice today and results obtained using numerical models with different levels of refinement. Since the entire matter (specifically the debris) was considered classified by the investigating magistrate in the immediate aftermath of the bridge collapse, this work is based entirely on publicly available material. [ABSTRACT FROM AUTHOR]

To solve the traffic problem over the Gan river connecting the two core regions in Nanchang City, a number of rapid traffic channels have been built in recent years. Among them, Chaoyang Bridge is very famous for its innovative structure and aesthetic appearance, which is regarded as a landmark in the city. The design conception of Chaoyang Bridge finally picked the six-tower single plane cable-stayed composite bridge after the study of many alternative designs. High standards and many key technologies were adopted in this project to ensure the success of the bridge. This paper introduces the general background, technical standards, bridge design, landscape design, bridge construction and research on some key issues of Chaoyang Bridge. The experience obtained in this project can serve as a source of reference for the construction of similar bridges in the future. [ABSTRACT FROM AUTHOR]