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Standards for the design of bridges, buildings and other infrastructure specify design loads for climatic hazards such as temperature, snow, wind, and floods based on return periods presented in maps or tables that account for regional differences. These design loads were developed from statistical analyses of historical hazard data under the assumption that the past is representative of the future. Climate change may affect the frequencies and intensities of environmental hazards which, depending on regional variations, raises questions as to whether structures designed to current specifications will meet minimum safety standards over their future service lives. This paper critically appraises issues related to using historical hazard data for future designs. It reviews basic principles of uniform reliability, that modern design codes use as the basis for ensuring minimum levels of safety, describing the relationship between hazard return periods, structural reliability, risk and the maximum loads expected within a structure's service life. Simple examples involving wind effects on structures demonstrate how to calibrate structural design hazard maps for climate-related extreme events to meet the minimum standards of safety implied in current specifications. The paper also introduces a possible practical approach to account for climate change when designing new structures and assessing the safety of existing facilities. [ABSTRACT FROM AUTHOR]

The LT‐bridge construction method for the material‐saving and fast construction of post‐tensioned concrete bridges Owners of infrastructure buildings will face enormous challenges in the coming years. Many engineering structures, especially bridges, need to be renovated or rebuilt. They are either no longer able to withstand the current loads or have developed durability problems. Discussions with owners have shown that rapid construction progress is crucial for bridge replacements. The construction sites should disrupt the normal flow of traffic as little as possible. As a result, a new, resource‐saving, and fast construction method for bridges has been developed. Innovative prefabricated elements for the longitudinal girders and the deck slab were developed to fulfill these requirements. The prefabricated elements are connected by reinforcement and an in‐situ concrete layer at the construction site. A comparison of the environmental impact based on the construction materials (life cycle phases A1–A3) between a construction section of an LT‐bridge and a typical German motorway bridge shows a lower global warming potential for the new bridge construction method due to the savings in construction materials. The feasibility of this new construction method was demonstrated by a pilot project in Austria. [ABSTRACT FROM AUTHOR]

Experimental investigation on the fatigue behavior of spot‐welded reinforcement – Applications of semi‐precast elements in bridge construction In recent years, various applications for semi‐precast elements in bridge construction have been developed at the Institute for Structural Engineering at TU Wien. As in most cases spot‐welded reinforcement is used within the elements and special attention must be paid to material fatigue in bridge construction, an investigation thereof is of highest importance. After a brief overview of the possible implementations of the elements as well as standards regarding material fatigue, the experimental investigations on the fatigue behavior are presented. The experimental program consists of the testing of 18 axial‐loaded reinforcement bars with spot‐welded transverse elements as well as 12 large‐scale cycling bending tests. The findings confirm the existence of a residual phase in the realistic large‐scale system, resulting in a time period between the first rupture of a reinforcement bar and the total collapse of the system. This behavior is seen as advantageous for the application in practice, as it results in an additional reaction time for possible construction measures. [ABSTRACT FROM AUTHOR]

The article provides information on the availability of the fib Bulletin 109, which focuses on the management, testing, and monitoring of existing concrete structures. It emphasizes the importance of maintaining aging infrastructure to ensure safety and functionality. The bulletin offers guidelines for data acquisition, condition assessment, performance prediction, and decision-making for existing structures. The article also mentions the upcoming fib Bulletin 110, which will address the management of post-tensioned bridges. It highlights the fib Symposium in Christchurch, New Zealand, which will showcase resilience to natural hazards and sustainable design in concrete structures. The article concludes with details about the fib PhD Symposium in Budapest and the International Conference on Concrete Sustainability in Guimarães, Portugal. It briefly introduces Aurelio Muttoni, a civil engineer with expertise in structural concrete and bridge design, who has made significant contributions to the field and received multiple awards. [Extracted from the article]

Various random factors in the bridge construction process directly affect the safety of the bridge life cycle. The existing theories on the reliability of bridge structure mainly focus on the reliability of components and the reliability of the bridge structure system in the completion and operation stages, while the research on the reliability of the structure system in the construction stage is relatively lacking. Therefore, this paper proposed using the Copula function to calculate the reliability index of the bridge structure construction process system. The basic theory of the Copula function was introduced in detail, and the formula was improved according to the actual situation of bridge construction. Finally, the sensitivity analysis of bridge system reliability was carried out. The research results showed that the method proposed in this paper based on Copula theory to calculate the reliability index of the bridge structure construction process system has strong applicability, simple calculation, and can be used in conjunction with the "interval estimation method", which is suitable for large and complex bridge structural engineering. At the same time, the conclusion that the influence of failure mode correlation on structural reliability should not be ignored in the actual engineering construction process is confirmed. [ABSTRACT FROM AUTHOR]

Many small-scale experimental, field, and empirical studies on bridge scour are available, however a large-scale study on local scour at a complex pier with wide variation in design parameters is still lacking. In this study, a country-wide assessment of local scour at complex piers of 239 bridges in Bangladesh is made. The hydrologic, hydraulic, and sediment data required in the assessment are obtained from secondary sources, primary measurements and samples, and numerical model simulations. An incredible number of 239 field visits are made, 1434 km of bathymetric surveys are carried out, and 478 samples of bed soils are collected and analyzed. The local scour depth is estimated using a complex pier configuration with pier, pile, and pile cap dimensions selected in consultation with structural and geotechnical engineers of bridge design. Flood frequency analysis and the HEC-RAS model simulation are used to estimate the hydrologic and hydrodynamic parameters needed in the assessment. A number of empirical formulations are used to estimate and compare the design local scours. The formulae of Melville and Coleman, Jain and Fischer, and Richardson are found to be dominant when deciding the design local scour depth at the bridge piers. Suggestions are provided to include a few additional equations in scour estimation and to develop a unified Bangladesh standard for scour depth estimation. The findings and recommendations of the study would be useful in planning and designing bridges in alluvial deltaic settings, particularly in the selection of empirical methods and mainstreaming of complex pier configuration in bridge scour assessment. [ABSTRACT FROM AUTHOR]

As structures crossing waterways, bridges are obstacles to vessels. Vessel-bridge collisions are inevitable. They not only involve the safety of vessel passage but also seriously affect the safe operation of bridges. Vessel-bridge collisions cause not only huge economic losses and casualties but also severe political and environmental losses. Vessel collision safety of existing and new bridges is one of the key technical problems that engineers and bridge managers must solve. Comprehensive consideration of vessel-bridge collision risk loss and structural performance in the design stage to achieve optimal cost over the life cycle is an important aspect of bridge design. Based on the current life-cycle design theory of engineering structures, this paper proposes a theoretical framework for vessel-bridge collision optimization design based on the life cycle, which includes three parts: vessel-bridge collision probability analysis, vessel-bridge collision vulnerability analysis, and vessel-bridge collision hazard. Taking the minimum cost of the bridge structure in the design service life period as the objective function, the optimization design model and design process of vessel-bridge collision based on whole life are established, and the key problems to be solved in each part are expounded. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shenzhen University Science & Engineering is the property of Editorial Department of Journal of Shenzhen University Science & Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The editorial discusses a themed issue on "Multi-Hazard Effects on Engineering Structures" in the Proceedings of the Institution of Civil Engineers journal. The issue aims to showcase recent research developments in understanding the behavior of structures subjected to multiple hazards, the performance of structural response modification devices, developments in codes and standards, probabilistic multi-hazard structural engineering, and measurement and tracking of condition and performance over the lifespan of structures. The editorial emphasizes the importance of studying and addressing the physical and socioeconomic losses caused by multiple hazards and their impact on society. It also highlights the need for scenario-based and site-specific designs and performance assessment for built infrastructure. [Extracted from the article]

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]

Prestressed concrete box girders with web tendons and unbonded transverse prestressing With the introduction of regulations and guidelines for the design of civil engineering structures (BEM‐Ing) especially for the calculation and design of concrete bridges (part 1, section 2), road bridge construction using prestressed concrete will change. For the first time since 1999 the arrangement of internal tendons in webs of box girders, it is permitted again. However, in order to avoid the shortcomings observed in some road bridges, which result, among other things, from a insufficient compaction of the concrete in the webs, stricter boundary conditions for the use of the bridge tendons in road bridge construction will be anchored in the future, while their possible applications in railway bridge construction will remain unchanged. In addition, it is strongly recommended to design road slabs of large width with transverse prestressing. For the deflection limitation of transversely prestressed road slabs, the maximum prestress force is limited in BEM‐Ing, which can be used to determine the required plate thickness by controlling of the concrete tension stresses. This article provides hints on the design and construction of prestressed concrete box bridges according to the new BEM‐Ing and shows which component dimensions result from the new rules. [ABSTRACT FROM AUTHOR]

On the introduction of post‐tensioning forces into thin‐walled box girder cross‐sections In the course of a research project currently being conducted at the Institute for Structural Engineering at the TU Wien, box girder cross‐sections consisting of thin‐walled semi‐precast concrete elements are being investigated for their use in bridge construction. The box girder cross‐sections are assembled segment by segment on the construction site and tensioned together with external post‐tensioning to form a self‐supporting bridge girder. Subsequently, the web, floor and deck slabs are completed with in‐situ concrete, thus producing a monolithic structure without joints. The post‐tensioning of the thin‐walled box girder cross‐section poses a particular challenge. In this paper, a new approach to the introduction of post‐tensioning forces in thin‐walled box‐girder cross‐sections is presented, based on experimental investigations carried out and their analysis with a nonlinear FE calculation. Two different manufacturing methods of the blisters were investigated, on the one hand a prefabricated construction method and on the other hand a cast‐in‐place method. It has been shown that the production of blisters as precast elements is preferable for the introduction of post‐tensioning forces into thin‐walled box girder cross‐sections due to the shear joint created by the in‐situ concrete construction method. [ABSTRACT FROM AUTHOR]

The structural development in bridge engineering along with efficiency have got much attention in few decades. Leading to the development, Optimization of structure established on mathematical analysis emerged mostly employed strategies for productive and sustainable design in the bridge engineering. Despite the widespread knowledge, there has yet to be a rigorous examination of recent structural optimization exploration development. Thus, the primary objectives of this paper are to critically review previous structural optimization research, provide a detailed examination of optimization goals and outline recent research field limitations and provide guidelines for future research proposal in the field of bridge engineering structural optimization. This article begins by outlining the relevance of efficiency and sustainability in the bridge construction, aswell as the work done required for this review. Suitable papers are gathered and followed by a statistical analysis of the selected publications. Following that, the selected papers are evaluated in terms of the optimization targets as well as their spatial patterns. Structure's optimization four key steps, includingmodeling, optimization techniques, formulation of optimizationconcernsandcomputational tools, are also researchedandexaminedindepth. Finally, researchgaps in contemporary works are identified, as well as suggested guidance for future works. [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 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]

Technologies and developments in precast segmental bridge construction Since the beginning of the European post‐war era, prestressed concrete bridges have been constructed from fully prefabricated superstructure segments without additional in‐situ concrete connections. This construction method, commonly known as precast segmental bridge construction, enables extremely economical and fast construction methods due to the minimisation of production steps on the construction site and is therefore now being used worldwide with increasing tendency. This article first examines the development and worldwide usage of precast segmental bridges based on an evaluation of an international database for engineering structures. Subsequently, certain key technologies in the production of precast segments, the structural design of joints and tendons, as well as erection methods of precast segmental bridges according to the current state of the art are presented. With a look at some recent research activities, the application of innovative construction materials such as high‐performance concrete and carbon fibre reinforced polymers in precast segmental construction and the resulting design possibilities are discussed. Finally, an outlook into a possible future of precast concrete construction in a digitalised construction industry is given on the basis of several approaches of the currently ongoing research programme SPP 2187. [ABSTRACT FROM AUTHOR]

Steel-concrete composite beams find extensive application in bridge construction, offering adaptability to complex terrains and structural advantages. Nevertheless, a persistent challenge lies in local instability, especially in steel beams with large aspect ratios. This study proposes stirrup-confined concrete-filled steel tube (CFST) composite beams as a solution to enhance structural performance by mitigating local instability. The research comprises comparative tests, numerical simulations, and theoretical examinations of rectangular CFST composite beams. Results demonstrate a significant improvement, with a 40% increase in flexural stiffness and a 10% increase in ultimate bearing capacity compared to traditional composite beams. Stirrup confinement effectively limits cross-section slip between the steel tube and infilled concrete, resulting in slip measurements of 0.72 mm at the end of loading. Examination of aspect ratios reveals substantial enhancements, showing a 65.6% increase in flexural stiffness and a 54.7% increase in ultimate bearing capacity as aspect ratios increase. Concrete strength grade exhibits minor effects, with slight improvements as the grade increases. Steel yield strength significantly influences ultimate bearing capacity, with a maximum 24.4% increase in higher-strength steel. Moreover, the steel content ratio enhances both flexural stiffness (up to 40.2%) and ultimate bearing capacity (up to 34.6%) with an increased steel ratio. Increased concrete slab thickness leads to improvements of up to 18.3% in flexural stiffness and up to 10.1% in ultimate bearing capacity. Formulas for predicting the flexural stiffness and bearing capacity of rectangular CFST composite T-beams are developed, offering practical guidance for optimizing their performance in structural engineering applications. • Comparative analysis shows CFST beams outperform traditional ones in stiffness and capacity. • Stirrups in CFST beams enhance steel-concrete bond, improving structural integrity. • Steel ratio and tube aspect are key in CFST beams' stiffness and capacity; other factors are less influential. • Formulas for calculating the flexural stiffness and bearing capacity of rectangular CFST composite T-beams are proposed. [ABSTRACT FROM AUTHOR]

The anthropogenic activities affect the river channel as well as the whole system in different magnitudes and dimensions. Barakar River, the main tributary to the Damodar River in eastern India, is modified by several engineering structures. Hydrological parameters, such as monthly discharge, peak flow discharge and geomorphological factors, such as gradient, width–depth ratio, grain size, braid–channel ratio, sinuosity ratio, riffle-pool sequence, and stream power are taken into consideration to highlight the significant alterations of the river due to dam and bridge construction. The alterations are assessed with the help of hydrological data, satellite images, and digital elevation data along with field survey. The downstream section of the dams, the river is characterised by high braiding, sinuous, total and unit stream power along with the presence of a box-shaped bedrock channel, high gradient, bed coarsening and armouring due to the release of high-velocity sediment-free 'hungry water'. In the upstream reach, the grain size decreases towards the dam, and it increases suddenly with poor sorting at the immediate downstream regime of the dam. The effects of bridges on the Barakar river morphology include an increase of gradient, width and depth of the river channel at the downstream of the bridges. The construction of bridges influences riffle-pool sequences. Thereby, the pool depth spacing is greater than the riffle crest spacing. However, the integration of natural as well as human-induced factors can be the best approach to understand the anthropogenic alteration of the river. Moreover, construction of some check dams at the upper section of the tributaries of the Barakar River can be very effective for morphological stability. [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]

The conceptual design hither to has been an individualistic approach practiced over a long period of time and not taught in universities. However, the conceptual design approach is very important to produce sound and sustainable structures. Engineers like Robert Maillart, Alexandre Sarrasin, Eugéne Freyssinet, Joerg Schlaich and Christian Menn significantly contributed to the evolution of today's international state‐of‐art technology and the cultural value of modern engineering structures. Billington called efficiency, economy, and elegance as common denominator for conceptualization of bridge design to counter countless anonymous, frequent utility structures based on mere technical and economic criteria. Many iterations of the design process are required at this stage to refine the concept for design and construction to adhere to functional, sustainability, financial and other constraints like right of way, etc. The tools used for analysis for investigations and iterations of the options may not necessarily be refined ones during conceptual design stage. The designer should have developed creative skills having a bent of mind for architecture and an architect having a broad insight in to structural engineering to render the best of the concept designs. While the structural designer must have a profound knowledge of engineering and available technologies, the architect can contribute in developing broad culture in many and important contextual aspects. [ABSTRACT FROM AUTHOR]

Featured Application: The conclusions of this paper could be useful for practicing structural engineers, mainly in the first stages of the conceptual design of arch bridges. In tied-arch bridges with a single arch, the deck is usually suspended from the arch by means of a single set of cables, pinned at both ends and anchored to the centerline, using either vertical or Nielsen-type hanger arrangements. When properly designed, this layout can significantly reduce forces and deflections under loads that are symmetrical with respect to the plane of the arch. However, it does not contribute to the support of nonsymmetrical loads, such as eccentric loads distributions or wind loading, and does not reduce the sensibility of the arch to out-of-plane buckling. Thus, this paper studies how a cable arrangement composed of two sets of lateral hangers, attached to both edges of a deck, can be very suitable to address these problems. Firstly, it is demonstrated that the structural behavior under symmetrical loads improves with respect to the bridge with centered hangers. Secondly, it is shown how nonsymmetric loads are partially carried by structural systems (such as the transversal stiffness both of the arch and the deck) that would remain inactive for tied-arch bridges with centered hangers, leading to a general reduction in the forces and the deflections of the bridge and in the critical buckling load of the arch. [ABSTRACT FROM AUTHOR]

Two examples from practice for shear capacity of textile‐reinforced bridge decks Textile‐reinforced concrete (TRC) for new constructions combines high‐performance textiles with a new generation of high‐strength concretes. Due to the corrosion resistance of the non‐metallic reinforcement, the use of TRC for exterior applications is promising, especially with freeze‐thaw and de‐icing salt exposition. The concrete cover and dead loads can be reduced and the production of slender structural elements as well as thin slabs without additional waterproofing or protective decking becomes possible. During the design of several bridges in Remstal and in Ottenhöfen, theoretical models and experiences from previous research projects were used to apply TRC slabs without shear reinforcement. Accompanying the production and construction works, experimental investigations of shear capacity were carried out for quality control of the execution and for validation of assumptions. The present article shows the application potentials and challenges for the use of TRC in civil engineering structures. [ABSTRACT FROM AUTHOR]

In this paper, the significance of application-oriented fundamental research on concrete and reinforced concrete structures for progress regarding practical applications to structural design is addressed based on four examples. They were treated in a joint research project of Vienna University of Technology and Tongji University. The first topic refers to sudden heating or cooling of concrete structures, the second one to high-dynamic strength of specimens made of cementitious materials, the third one to structural analysis of segmental tunnel rings used in mechanized tunneling, and the fourth one to serviceability and ultimate limit states of concrete hinges used in integral bridge construction. The first two topics deal with exceptional load cases. Results from the fundamental research call for improvements of state-of-the-art simulation approaches used in civil engineering design. The last two topics refer to reinforced concrete hinges used in mechanized tunneling and integral bridge construction, respectively. Integrative research has led to progress regarding the verification of serviceability and ultimate limit states. In all four examples, results from fundamental research are used to scrutinize state-of-the-art approaches used in practical structural design of civil engineering structures. This allows for identifying interesting directions for the future development of design guidelines and standards. [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]

Copyright of Tyragetia is the property of National Museum of History of Moldova and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Modern buildings should provide some degree of safety against severe earthquakes. However, it is not economically feasible to construct buildings that withstand extreme loads without avoiding damage. In performance-based design, structural engineers and owners work together to achieve the best possible balance between construction cost and seismic performance. In this study, by employing a metaheuristic optimization, we have tried to extend the concept of performance-based design to retaining wall structures. According to the AASHTO LRFD Bridge Design Specifications, permanent displacement of retaining structures are tolerable, as long as the movement does not lead to unacceptable damage to the structure or facilities located in or near the moving earth. The decision on performance expectations needs to be made by owners with structural engineers providing a realistic assessment of the cost of designing to avoid the movement. To make this assessment possible, we developed a multi-objective optimization framework for simultaneous minimization of the construction cost and the permanent displacement of cantilever retaining walls. The effectiveness of the proposed framework was evaluated in the design of a typical cantilever retaining wall of 8 meters in height, once with both a toe and heel slab and once with either of them. The results indicated that obtaining the Pareto front of optimal solutions for these objectives, provides useful information that helps owners to select a solution that is the most economical in a trade-off between the construction cost and performance expectation. [ABSTRACT FROM AUTHOR]

The past few decades have witnessed a rapid increase in the role of the architect in the design of the once sacrosanct area of engineering – bridge design. Reasons for this relative decline in the engineer's role are many and varied, but must include the overemphasis on detailed analysis at the expense of understanding and creative design in engineering courses and the alarming reduction in structural education from engineering courses. With software now readily available to perform detailed structural analysis there is an opportunity to rebalance engineering courses towards much greater emphasis on understanding and design involving new approaches to analysis that can directly assist rational decision making. This paper demonstrates how simple, physically based, analyses can aid rational decision making in bridge design and suggests that such approaches could play a wider role in engineering courses. By way of illustration, these approaches are applied to the iconic, much copied, gravity balanced cable-stay Alamillo Bridge designed by Calatrava. This example also demonstrates the inefficiency of this bridge form and shows how such approaches, applied at an early design stage, could help bring rational engineering judgement back into bridge design at a time when the planet can ill afford such unsustainable solutions. [ABSTRACT FROM AUTHOR]

This paper presents a new experimental-numerical simulation framework for investigating the impacts of unconventional material behaviors on the global response of structural systems. The new framework is specifically designed to address: (1) knowledge gaps related to the lack of analytical tools for predicting the behavior of materials under nontraditional loading environments, and (2) high costs associated with large-scale experimental testing. The new simulation method, named material testing integrated (MTI) simulation, incorporates physical material test data into numerical simulation of structural system or component to provide more accurate structural performance evaluation based on reliable constitutive behavior of materials. To demonstrate the new concept, this paper utilizes MTI simulation to study and compare the seismic response of reinforced concrete (RC) bridge columns rehabilitated with steel and shape memory alloy spiral reinforcement. The experimental-based MTI simulation responses of the columns are compared with that of conventional numerical simulation. The results show that the test data utilized in the MTI simulation are well reflected in the global seismic response of the RC columns. [ABSTRACT FROM AUTHOR]

The structural form of a bridge during construction is strongly affects its structural form after completion, with innovative construction processes sometimes leading to innovative bridge designs. It is thus important to consider the construction process during bridge design methods. This approach could be applied not only to new construction but also to replacements, reconstructions, or reinforcements. One of the authors has previously systematized the structural forms of bridges and clarified the principles. This study aims to extend these principles to construction systems. Changes in the structural systems of the construction processes and systematization of the relationship between a completed bridge and construction process in a design are illustrated. Three types of structural systems (suspension, beam, and arch systems) were analysed in terms of material efficiency and time efficiency for corresponding construction states of construction, completed, retrofitted, and retrofitting. Each system exhibited different levels of efficiency at different levels of efficiency at different states of construction. This systematization enables the application of a variety of conventional construction methods in a system. This would be helpful in developing new construction methods and designs for bridges. [ABSTRACT FROM AUTHOR]

This paper describes the design and construction of Ohmi–Odori Bridge in Japan, which is the world's first multi-cell extradosed prestressed composite bridge with corrugated steel webs. Structurally, the bridge combines two new technologies: a composite prestressed concrete bridge with a corrugated steel web to reduce the dead weight of the main girder and an extradosed bridge to allow a longer span length. Several innovations were used on this bridge, including a three-cell box cross-section, adopted for the first time for the main girders of a bridge using corrugated steel webs, and a steel–concrete composite structure adopted for the cable anchorages. In 2006, the bridge was honoured with the highest award for a bridge project, the Tanaka Prize awarded by the Japan Society of Civil Engineers. [ABSTRACT FROM AUTHOR]

There is a large number of masonry arch bridges on the rail networks in Europe and other parts of the world. However, the mode of response of masonry arch structures subjected to railway loading is little understood. To address this, an experimental study involving large-scale physical models of backfilled masonry arch bridges subjected to railway loading conditions was conducted. The study explored the influence of the rail track–bed system on bridge behaviour and load-carrying capacity. The tests results indicated that the track–bed system fundamentally alters the mode of response of the bridge system and significantly increases load-carrying capacity. Using the same test facility, load tests were also used to explore and characterise the behaviour and performance of damaged arch bridges. The results obtained suggest that, although there is likely to be a reduction in overall capacity, even a significantly damaged arch bridge can still perform adequately under loading. This has important implications for bridge owners and assessment engineers. [ABSTRACT FROM AUTHOR]

Network Rail (NR) manages over 60 000 bridge spans, many of which are more than 150 years old. Having contemporary capability information for these ageing assets is vital for the safe and effective management of the rail network. NR has never before had comprehensive, contemporary capability information, and has relied on assessments up to 18 years old. In some cases, assets did not have assessments so their ongoing performance alone was relied upon. Without reliable data on the strength of these structures it would be impossible to operate the railway safely, deliver effective maintenance, decide when repair intervention is required or plan future development of the network. This paper describes the current approach to the assessment of bridges on the railway and the innovative work that has been undertaken to improve the efficiency of assessment and deliver the considerable volume of bridge assessments required to bring strength capability information to an acceptable standard. The paper will also explore the potential of consistent data collection and recording for the better management of the asset as it inevitably deteriorates. [ABSTRACT FROM AUTHOR]

The fundamental frequency of vibration of a bridge deck is a key parameter that represents the dynamic characteristics and the condition of the superstructure. This paper reviews the different empirical and/or theoretical formulae that have been proposed in the past. The classical vibration theory of beams and plates was simplified in order to clarify and review the general philosophy behind the previously proposed formulae. On the basis of the results obtained from limited dynamic tests performed by the authors on a number of reinforced concrete bridges and the results of limited tests conducted by other researchers, a formula for the first bending natural frequency of a bridge deck was derived. Moreover, as new applications, new practical formulae are introduced that can be used for estimating the initial dimensions of a deck cross-section for simple span bridges, which are particularly suited to bridge-widening projects. The first bending natural frequency/period of the bridge deck and its corresponding cross-sectional properties are considered here as functions of the bridge main span length. [ABSTRACT FROM AUTHOR]

Abstract A continuous bridge in high-speed railway is close to several known faults in China. Those faults, respectively at different distances from the bridge site, will produce different ground motions with the different ratios of vertical component to the horizontal component at the bridge site. It is necessary to identify the influence of vertical ground motions on the seismic responses and vulnerabilities of the track-bridge system. This paper solved this problem by carrying out an incremental dynamic analysis (IDA) and a further seismic fragility analysis on a widely used continuous bridge in China. The results show that the damage probabilities of most bridge and track components increase along with the increase of vertical part in ground motions. This trend is significant for the sliding layer of track part in the longitudinal direction and the piers of bridge part in any direction, however, insignificant for the bearings of bridge part in any direction. Moreover, this trend is more significant for the track part across the girder gap due to the different seismic responses of adjacent bridges. The seismic design of track-bridge system should rigorously take the vertical part of ground motions into account. Highlights • Seismic damages of track and bridge components increase with vertical ground motions. • Effects of vertical ground motions on track components between bridges are complex. • Vertical ground motions should be considered for a track-bridge seismic design. • A combination of bridge and CRTS II track is reasonable under earthquakes. [ABSTRACT FROM AUTHOR]

A light rail passenger transportation system is being built in Seattle, WA, USA, that traverses Lake Washington over an existing pontoon bridge. The water level in Lake Washington changes throughout the year. This causes rotations of the transition spans, which are needed at each end of the bridge to carry traffic between the fixed, land-based structure, and the floating structure. This paper explains a novel method, the Curved Element Supported Rail (CESuRa) system, that provides rails with the ability to undergo joint rotations at the ends of the transitions spans without risk of damage, while maintaining full vertical support of the track across the joint. The geometric characteristics on which it depends for proper operation, considerations that must be accounted for when using the system for other applications in the future, and an overview of the implementation of the system on the floating bridge are discussed. [ABSTRACT FROM AUTHOR]