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Featured Application: The design concept and analysis method can be applied to the aesthetical and mechanical design of urban landscape bridges. The first main and secondary collaborative Y-shaped steel box arch bridge under construction in China is a rarely seen innovative practice among bridges already built at home and abroad, which is an attractive engineering research topic in the field of advanced bridge design and construction, and the investigation of this bridge has made a groundbreaking contribution. The structure of unconventional thin-walled steel box arch ribs is very novel, abandoning the traditional two-dimensional arch rib structure form and adopting the new structural mode of single–double combination and joint working of main and secondary arches. However, for this innovative design, many technical difficulties including innovative design details, mechanical behavior of thin-walled structures and construction methods still need to be pioneeringly explored and thoroughly researched. In this paper, the innovative design concept of unconventional thin-walled arch ribs for spatial Y-shaped steel box arch bridges is described, and a comparative analysis with the corresponding conventional single arch rib structure is carried out. Due to the limitations of the common conventional arch bridge research methods, a combined global and local finite element method is used to analyze the static and dynamic properties of the structure, and the shear lag effect of the thin-walled steel box arch ribs is studied in a pioneering and exploratory approach. In addition, the stress distribution of the bifurcated section of the arch ribs and the configuration of the diaphragm are analyzed in detail to verify the reasonableness, advantage and applicability of the innovative design. The results show that the main and secondary arch collaboration Y-shaped steel box arch bridge has reasonable structure and superior mechanical properties and has a greater value for promotion The design concept and analysis method are worthy of use as a reference for the aesthetical and mechanical design of similar spatial Y-shaped arch bridges in the future. [ABSTRACT FROM AUTHOR]

With the increasing span of cable-stayed bridges, the towers are getting higher and higher, and the stiffening beams are becoming more and more slender. The increase in span causes the axial pressure of the beams and towers to increase rapidly, and the sag effect of the cables, geometric nonlinearity, and material nonlinear effects are significantly increased. The influence of these disadvantages greatly reduces the stability of the cable-stayed bridge, and the stability of the cable-stayed bridge becomes prominent. In this paper, the finite element method is used to analyze the first kind of stability problem and the second kind of stability problem of cable-stayed bridges. On this basis, a large-span prestressed concrete (PC) cable-stayed bridge is taken as an example to analyze and compare the two types of stability problems of the bridge during the construction phase and the operation phase. Besides, the model experimental study on the stability of the bridge during the maximum double cantilever construction period was carried out. The theoretical values and the model test results are compared to verify the correctness of the calculation method and design theory, which may provide a reference for the design, construction, and scientific research of cable-stayed bridges. [ABSTRACT FROM AUTHOR]

Many bridges would be washed away due to giant tsunamis caused by the anticipated Nankai Trough earthquake. The accelerated bridge construction (ABC) concept should be applied to temporary bridge construction to save on-site construction time and help roads reopen immediately after the event. In this paper, a temporary bridge using precast reinforced concrete (RC) blocks with connections composed of steel shear keys and carbon fiber–reinforced polymer (CFRP) sheets is proposed. The proposed bridge facilitates rapid recovery from natural disasters and accordingly enhances disaster resilience. Bending and shear tests are conducted to investigate the effects of the proposed connection on the structural performance of beams. The experimental results indicate that the connection with an adequate CFRP sheet length provides sufficient flexural capacity for temporary bridges and does not negatively affect the shear capacity. Moreover, a 3D finite-element (FE) model is applied to simulate the bending tests. The FE model provides good agreement with the experimental results and can be applied to design the structural details of full-scale RC blocks. [ABSTRACT FROM AUTHOR]

Excessive fastener spacing, which results from construction errors (the bridge construction error and the track layout error) and environment temperature, is a possible safety risk for train and track structure. To address this problem, this paper selected a CRTSIII ballastless track-bridge section as the engineering case, and established a thermal-mechanical track-bridge coupling model. The maximum fastener spacing was calculated based on the model, and the dynamic and static characteristics of train and track under the different fastener spacing were compared. The results show that under the combination of construction errors and ambient temperature, the most unfavorable fastener spacing is 755 mm; with the increase in fastener spacing, the longitudinal resistance of fasteners first reaches the limit in the static safety indexes; the rail vertical dynamic displacement first reaches the limit in the dynamic safety indexes. Therefore, maximum fastener spacing of CRTSIII ballastless track structure depends on railway operation and maintenance, train speed and local environment. [ABSTRACT FROM AUTHOR]

With the increase of bridge-required demolition/dismantling for reconstruction or modification, the early warning of construction emergencies is greatly needed for monitoring the structural safety of bridges under construction. In this paper, based on the multi-source data of nearby construction and demolition construction of a large-span RC arch bridge in China, the Analytic Hierarchy Process (AHP) method is adopted to analyze the multi-source data and set the early warning threshold for bridge safety in construction. According to the analytical results, a reasonable evaluation of AHP factors can improve the accuracy and timeliness of safety early warning in the structural safety monitoring of bridges during the construction process. The weight of the monitoring data in AHP should be assigned according to its reliability, stability, and importance. Bridge safety assessment of nearby construction having harmful vibration should prioritize dynamic bridge monitoring by cooperating with multi-source data, including stress, and deformation monitoring of the bridge is necessary. The assessment results proved that multi-source data, including but not limited to structural stress and deformation monitoring data, vibration data, theoretical prediction data, environment data such as temperature data, and construction/maintenance history data, are necessary for safety monitoring and early warning of construction with specifications related to bridge construction. The early warnings triggered by the evaluation results successfully ensure the safety status of the bridge during nearby construction and demolition construction, which shows the proposed method can provide a guideline for comprehensively evaluating and early warning of the status of bridge construction. [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]

To ensure the safe construction of bridge pile foundation in karst area, it is necessary to accurately detect the unfavorable geological conditions such as karst cave and soft layer before excavation. In this paper, the transient electromagnetic method is used to probe the geological conditions near the pile Y1 of an interworking main bridge in China's Hunan Province. By arranging 5 measuring lines at the pile Y1, the voltage variation laws of 21 monitoring points on each measuring line are obtained, and the resistivity variation cloud maps at the measuring line positions are inversed. The results show that the voltage signals at line 1 and line 5 are obviously abnormal, and the resistivity varies greatly within 50 m underground depth, which indicates that there may be adverse geological conditions such as karst cave and carbonaceous limestone interlayer. Further, through on-site hole digging and sampling, it is found that the slag sample in the area above 50 m of the stratum of pile Y1 is wet, and the slag sample below 50 m is dry without argillaceous interlayer, which verifies the effectiveness of transient electromagnetic detection method. Because the transient electromagnetic detection technology does not need drilling and the detection process is convenient, it may provide a new means for quickly detecting the integrity of the bearing layer of bored cast-in-place pile in bridge construction. [ABSTRACT FROM AUTHOR]

In highway design, inverted-T bridge caps (ITBCs) have been extensively used in the United States. Depending on the project requirements, some ITBCs need to be skewed. In Texas, the traditional method of flaring the transverse reinforcement out is used to design the skewed ITBCs, as stated in the Texas Department of Transportation (TxDOT) Bridge Design Manual. However, this method has significant drawbacks in terms of design and construction. To solve the complexities of the traditional method, the skewed reinforcing method is proposed to TxDOT. In this paper, to enlarge the knowledge of the structural behavior and the economic impact of skew reinforcing in ITBCs, the nonlinear finite-element (FE) simulation and cost–benefit analysis of 96 full-scale skewed ITBC models are performed. The structural and economic performance of the specimens are investigated and compared according to the following design variables: (1) skew angle; (2) transverse reinforcement detailing; (3) amount of the transverse reinforcement; (4) presence of the end reinforcement; (5) size of the diagonal end reinforcement; and (6) the concrete strength. The finite-element analysis shows that skew reinforcing can achieve better structural performance than the traditional method in terms of stiffness, crack width, and the ultimate capacity. Moreover, the skew transverse reinforcement method considerably reduces the design and construction costs. [ABSTRACT FROM AUTHOR]

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The article presents summaries of papers related to bridge construction, published in other parts of the "ICE Proceedings" during 2003. The paper "Strengthening of London's Lambeth Bridge," summarizes the findings of the principal inspection and load assessment of Lambeth Bridge, which had identified a structural deficiency in the original construction of the arched steel ribs of the bridge. The paper "Shear strengthening of existing concrete bridges," deals with a new type of shear strengthening for existing concrete bridges. The paper "Thermal actions on a steel box girder bridge," focuses on steel box girder bridges.

The Shangqiu–Hangzhou high-speed railway is 794.55 km long with a design speed of 350 km/h. The third Wuhu Yangtze River Bridge stands out as the key project of the whole railway. Restricted by the site conditions, the bridge is an asymmetrical low-pylon cable-stayed bridge with a main span of 588 m. To overcome the technical challenges of low stiffness and unfavourable axial force induced by the low pylons, a box-truss type composite section with a strong box at the lower deck and a weak truss above was creatively used in the design of the main girder. In addition, parallel steel wire cables coated with a zinc–aluminium alloy and with a tensile strength of over 2000 MPa were developed to withstand the tremendous axial force in the inclined cables. These two innovative solutions were successfully implemented in the construction of the bridge. This paper describes problem solving through creativity by addressing a few key issues faced by the designers. [ABSTRACT FROM AUTHOR]

Featured Application: The research work herein is based on the construction of the Honghe Bridge in Zhuhai City. At present, the main body and pavement of the bridge have been completed, and the design scheme of the collision avoidance device has been adopted for the construction. The collision avoidance pontoons are being manufactured in the prefabrication plant. We believe that this will accumulate more experience in the future of ship collision prevention for bridges around the world. Ship-bridge collisions are one of the most common types of accidents, and bridge anti-ship collision devices are of great importance for bridge protection. First, a new type of assembled ultra-high performance concrete (UHPC) collision avoidance is proposed in this paper. The main components of the device are double-deck, two-way, densely reinforced ultra-high performance concrete floating boxes that are connected by high-strength bolts to form the whole structure and are equipped with steel supporting elements to form a collision energy dissipation device. The device is self-floating in water, is strongly energy absorbing due to plastic deformation, has a high degree of toughness, is corrosion resistant, and so on. This device also benefits from modular manufacturing, efficient installation, and easy replacement of damaged parts. Then, in this paper, the main parameters of the new collision avoidance, such as the material of the internal supporting elements, the wall thickness of the floating box, and the reinforcement ratio of the floating box, are optimized. Finally, a performance analysis and evaluation of the UHPC collision avoidance for the Honghe Bridge in Zhuhai City are carried out by using LS-DYNA program. The numerical results show that the new collision avoidance has significant advantages in reducing the ship–bridge collision force, prolonging the ship–bridge collision time, and protecting the ship. The results show that the assembled UHPC collision avoidance system is very effective for protecting ships and bridges in the event of a ship–bridge collision. [ABSTRACT FROM AUTHOR]

There has been a considerable progress in the reliability-based code development procedures. The load and resistance factors in the AASHTO bridge design code were determined using the statistical parameters from the 1970's and early 1980's. Load and resistance factors were determined by first fixing the load factors and then calculating resistance factors. Load factors were selected so that the factored load corresponds to two standard deviations from the mean value and the resistance factors were calculated so that the reliability index is close to the target value. However, from the theoretical point of view, the load and resistance factors are to be determined as coordinates of the so-called "design point" that corresponds to less than two standard deviations from the mean. Therefore, the optimum load and resistance factors are about 10% lower than what is in the AASHTO LRFD Code. The objective of this paper is to revisit the original calibration and recalculate the load and resistance factors as coordinates of the "design point" for prestressed concrete girder bridges. The recommended new load and resistance factors provide a consistent reliability and a rational safety margin. [ABSTRACT FROM AUTHOR]

Emerging transformable lattice structures provide promising paradigms to reversibly switch lattice configurations, thereby enabling their properties to be tuned on demand. The existing transformation mechanisms are limited to nonfracture deformation, such as origami, instability, shape memory, and liquid crystallinity. In this study, we present a class of transformable lattice structures enabled by fracture and shape-memory-assisted healing. The lattice structures are additively manufactured with a molecularly designed photopolymer capable of both fracture healing and shape memory. We show that 3D-architected lattice structures with various volume fractions can heal fractures and fully restore stiffness and strength over two to ten healing cycles. In addition, coupled with the shape-memory effect, the lattice structures can recover fracture-associated distortion and then heal fracture interfaces, thereby enabling healing of lattice wing damages, mode-I fractures, dent-induced crashes, and foreign-object impacts. Moreover, by harnessing the coupling of fracture and shape-memory-assisted healing, we demonstrate reversible configuration transformations of lattice structures to enable switching among property states of different stiffnesses, vibration transmittances, and acoustic absorptions. These healable, memorizable, and transformable lattice structures may find broad applications in next-generation aircraft panels, automobile frames, body armor, impact mitigators, vibration dampers, and acoustic modulators. Structural materials: Changing shape on demand A lattice structure that switches between different arrangements when fractured and healed has been developed by scientists in the United States. A lattice structure, like a network of struts, can improve a material's strength without significantly increasing its weight. This approach is seen in the design of bridges, but lattice-based structures are also used on smaller scales, for example, in battery electrodes or biomedical scaffolds. Qiming Wang from the University of Southern California, Los Angeles, and co-workers created a material in which the lattice can be modified dynamically for specific applications through an autonomous healing process. They 3D printed a transformable lattice structure made from a polymer. By heating the structure, they could change it from a so-called kagome lattice to a triangular lattice, thereby altering physical properties such as vibration transmission and stiffness. This transformation was entirely reversible. Existing healing experiments on self-healing bulk materials typically rely on manual contact of fracture interfaces. Development of 3D-architected lattice structures that can autonomously heal fractures or damages is still an outstanding engineering challenge. This paper presents a class of additively manufactured lattice structures that can autonomously heal fractures by first aligning fracture interfaces through a shape-memory process and then repairing fracture interfaces through a fracture-healing process. Through harnessing the coupling of shape-memory and self-healing, this paper also demonstrates reversible configuration transformations of lattice structures among states of different stiffnesses, vibration transmittances, and acoustic absorptions. [ABSTRACT FROM AUTHOR]

Since the Pelješac bridge construction project was awarded to the Chinese company China Road and Bridge Cooperation (CRBC) in January 2018, the Sino-Croatian relations reached a new high point. Since then, and contrary to Croatia's past activity and interest, Croatia not only opted to more actively participate in the "17+1" cooperation framework, but even stepped forward by hosting the latest "17+1" summit, held in April 2019. The rekindled relations have since been, on the surface, bursting with possibilities regarding investment, exchanges of personnel, and cooperation on various levels. However, years of neglect, especially on the Croatian side, had created a situation in which Croatia is critically falling behind in experts, Chinese-speaking talents, and various aspects of knowledge needed to support this level of cooperation. Furthermore, judging by the press releases and the lack of clarifications from the Croatian government regarding the short-term decisions and the long-term direction the renewed Sino-Croatian friendship is taking, general understanding of how concepts such as the "17+1" or the Belt and Road Initiative actually reflect on Croatia with regards to their influence on the wider regional and global circumstances is also lacking. This paper analyses the width of the uneven approach China and Croatia are taking in the development of their relations and will attempt to address the issues and challenges that could arise from this unevenness. [ABSTRACT FROM AUTHOR]

In the midst of the climate crisis, both in terms of ecological and social issues, creatives must seek innovative ways to trigger and support active change. Interrogating our ways of working has become essential: How can we support the whole ecosystem? How can we deeply engage people? How can we be more accountable for our actions? Responding to these concerns, this paper reflects on the benefits of applying ecoscenography in 'Glimpsing Air Pockets' creative process. It results in an immersive, multi-sensory dance theatre production which aim is collective wellbeing through active engagement and Nature connection. Original to Native American culture and recently recognized by New Zealand and India governments, I refer in my writing to terms such as Nature or Earth with a capital letter, granting them their personhood status with equal rights to human beings. Written as a deep artistic reflection, this paper demonstrates the importance of linking the Arts and Nature connection to create positive social and environmental change for a more connected and resilient future of our society and the planet. [ABSTRACT FROM AUTHOR]

The article discusses papers in the August 2012 issue of the "Practice Periodical on Structural Design and Construction" including a paper on the use of accelerated bridge construction (ABC) and prefabricated bridge elements, case studies of the optimization method for drilled shafts supporting bridge structures and a paper which proposes a seismic rehabilitation techniques for unreinforced masonry historic buildings.

The article discusses various reports published within the issue including two papers on the subject of pedestrian induced lateral vibrations of bridges, and another papers which deal on seismic issues.

The article discusses various reports about bridge testing and health monitoring published within the issue, including one about in-service evaluation of cable-stayed bridges by Armin B. Mehrabi and another about the assessment of bridge remaining fatigue life by Edward Zhou.

The article presents a list of papers of interest relating to bridge engineering, including "Characteristics of horseshoe vortex in developing scour holes at piers," by S. Dey and R.V. Raikar, and "Mineral based bonding of CFRP to strengthen concrete structures," by B. Taljsten.

A list of papers related to bridge engineering is presented. They include "Rapid bridge replacement: Processes, techniques, and needs for improvements," by Y. Bai and W. R. Burkett, "Membrane-based forms for innovative FRP bridge systems through structural optimization," by R. Burgueño and J. Wu and "Analysis and design procedure for FRP-strengthened prestressed concrete T-girders considering strength and fatigue," by H. A. Rasheed, K. H. Larson and R. J. Peterman.

Presents an introduction to the July 2003 issue of the journal "Bridge Engineering."

Studies have shown that in structures isolated with spherical sliding bearings, the seismic base shear increases when the vertical component of ground shaking is explicitly considered, since the dynamic variation of bearing axial force is passed on to the base shear due to the friction mechanism. In this paper, the effect of vertical shaking is systematically investigated in multi‐span concrete box‐girder highway bridges isolated with triple pendulum bearings. Grounded in the theory of bearing mechanics, a simplified method to predict the amplification of base shear with vertical ground shaking intensity in such bridges is developed and evaluated. The simplified approach is potentially applicable for bridge design based on equivalent static analysis. At low to moderate vertical intensities, the simplified method can capture the observed variation in the base‐shear coefficient with isolation system parameters. The differences in base‐shear amplification for bridge superstructure parameter variations are insignificant, and thus the method is widely applicable. At high intensity vertical ground shaking, the base shear coefficient can be affected by an uplift and impact phenomenon. Thus, application of the simplified method should be limited to motions with peak vertical acceleration up to 1 g; simulation with 3D motions is recommended for intensities beyond 1 g. [ABSTRACT FROM AUTHOR]

Use case‐based utility analysis of acquisition technologies in bridge construction BIM‐based project management is currently still under development in infrastructure and engineering, especially in bridge construction. Particularly in the execution phase, only research has been done on how information may be acquired digitally and automatically at the construction site. Automated data acquisition may greatly facilitate the acquisition of relevant data and information during the construction phase, it may increase safety and make more efficient use of personnel at a construction site, reduce workloads and ensure a short‐cycle information provision, thus optimizing costs. Basically, each data acquisition should serve a specific use case and be triggered according to the lean philosophy and the pull principle. So far, there is no standard or recommendation for the decision‐making process, which acquisition technology should be used for which use case in order to generate the greatest benefit. In this paper, a use case based utility analysis for data acquisition technologies in bridge construction is presented. Blind spots of previous research are addressed to ensure a structured and transparent decision‐making process. [ABSTRACT FROM AUTHOR]

UHPFRC Precast Segments for Sustainable and Resource‐Efficient Concrete Bridge Construction Many of the concrete bridges currently in use in Germany are in a deficient condition due to their age or design. However, increased traffic loads also highly contribute to the fact that many of the existing bridges will have to be replaced in the medium term. Due to the many advantages of concrete structures, it can be assumed that concrete bridges will continue to be designed and built in the future. In the light of the increasing consequences of climate change and the pressing need to reduce CO2 emissions also in the building industry as well, there is an urgent need for research into climate‐ and resource‐friendly as well as sustainable but also economical concrete construction methods. A promising approach to fast, effective and resource‐optimized as well as CO2‐efficient construction is the use of high‐performance materials such as UHPFRC in combination with precast segmental construction. In this paper, starting from a monolithic box girder bridge made of normal strength concrete, numerical calculations are used to investigate how much material can be saved in segmented box girder bridges by varying the concrete compressive strength (normal and high‐strength concrete as well as UHPFRC). The life cycle assessment subsequently carried out on this basis for life cycle phases A1 to A3 showed that, when the material is fully utilized, the use of UHPFRC leads to very resource‐efficient and sustainable structures compared with normal‐ and high‐strength concretes. [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]

ÖBB trough bridges with UHPFRC‐composite slab In the railway system of the Austrian Railway Association there are a lot of single span steel bridges with short span (<20 m) and without ballast bed. One of these bridges was the Auenbachbrücke, situated on the railway track Zeltweg–St. Paul in the Lavanttal (Kärnten, Austria), which should be replaced by a modern bridge structure with ballast bed. The main task in the design of the bridge construction was to maintain the existing top of the rails as well as the bottom height of the construction due to flood prevention issues. This task could be solved by using a steel trough bridge with transversal orientated UHPFRC‐composite slab, as shear connection crown dowels were used. In the present paper, the bridge construction is presented and the statically calculation as well as the corresponding testing are introduced. [ABSTRACT FROM AUTHOR]

In the process of cradle construction for high-pier, long-span, continuous, rigid-frame (HLCR) bridges, the strength failure and instability damage of the main pier will directly affect the bridge construction safety. Therefore, it is necessary to study the reliability of the main pier during the construction of HLCR bridges. This paper starts from the factors that easily affect the stability of the main pier during HLCR bridge cradle construction, establishes the resistance and load probability model of the main pier during the maximum cantilever stage and the maximum unbalanced load of the continuous, rigid-frame bridge's hanging cradles, fully considers the influence of random factors on the reliability of the pier, and calculates and analyzes the reliability index β through calculation examples. The results show that the changes of various random factors during the construction process have different degrees of influence on the reliability of the bridge pier. Our work provides a basis for the safe control of hanging cradles in the construction of HLCR bridges. [ABSTRACT FROM AUTHOR]

This paper proposes an equivalent plane algorithm of spatial stay cables using spatial rigid arms and the stay cable corotational coordinate system. The equivalent equations for the cable displacements and force elements are established, and the equivalent plane-element stiffness matrix of the spatial-cable element and its transfer matrix are derived. The matrix is automatically transformed into the plane-cable element model with rigid arm when the cable plane of the cable-stayed bridge is parallel. The spatial characteristic parameters of the cable plane are proposed, and the spatial effect of the spatial-cable plane on the internal force and deformation of the cable-stayed bridge is also analyzed. This equivalent plane algorithm is programmed into the bridge design and construction monitoring system procedure, and a comparison analysis with MIDAS software is also conducted. The proposed method can simplify the calculation model for the entire construction process of cable-stayed bridges with spatial cables and yield a good calculation accuracy. The equivalent plane algorithm has been successfully applied to the Jiayu Yangtze River Bridge (a kilometer-scale cable-stayed bridge). The results show that the number of stay-cable elements in the calculation model is reduced by 50%. The difference between the proposed method and the calculation result of a spatial-cable plane model is very small for a cable-stayed bridge with a spatial-cable plane, whether the initial tension is used or an unstressed cable is used. The proposed method provides an efficient and reliable calculation method for the design and construction of spatial-cable-stayed bridges. [ABSTRACT FROM AUTHOR]

Bridge design values for axle load and truck volume have increased since the 1960s, following the introduction of modern vehicle configurations, such as those of permit, special hauling, and emergency vehicles. Many highway bridges in the U.S. are estimated to be structurally inadequate, especially with respect to the shear capacity of the superstructure to carry these loads, and there have been numerous efforts to consider strengthening options for such older shear-deficient bridges. Techniques for enhancing the shear capacity of concrete bridge girders range from traditional approaches using steel and concrete (e.g., bolted steel plates) to newer approaches that utilize novel concepts and advanced materials, such as fiber-reinforced polymer (FRP) composites and shape-memory alloys. This paper reviews these shear strengthening techniques from a practical application standpoint, particularly with respect to their structural efficiency and constructability. The conceptual basis of each technique is described along with a summary of the advantages and shortcomings of each technique, followed by an overview of some representative field implementations and relevant design guidelines, if available. Finally, the concept of developing an assessment rubric is introduced to aid in identifying a potential shear-strengthening scheme for a particular project. [ABSTRACT FROM AUTHOR]

Highway bridges play an important role in traffic construction; however, accidents caused by bridge construction occur frequently, resulting in significant loss of life and property. The identification of bridge construction scenes not only keeps track of the construction progress, but also enables real-time monitoring of the construction process and the timely detection of safety hazards. This paper proposes a deep learning method in artificial intelligence (AI) for identifying key construction scenes of highway bridges based on visual relationships. First, based on the analysis of bridge construction characteristics and construction process, five key construction scenes are selected. Then, by studying the underlying features of the five scenes, a construction scene identification feature information table is built, and construction scene identification rules are formulated. Afterward, a bridge key construction scene identification model (CSIN) is built; this model comprises target detection, visual relationship extraction, semantic conversion, scene information fusion, and identification results output. Finally, the effectiveness of the proposed method is verified experimentally. The results show that the proposed method can effectively identify key construction scenes for highway bridges with an accuracy rate of 94%, and enable the remote intelligent monitoring of highway bridge construction processes to ensure that projects are carried out safely. [ABSTRACT FROM AUTHOR]

Despite the numerous advantages high-strength reinforcement (HSR) and high-strength concrete (HSC) offer over conventional materials, the practical use of these materials for bridge column design in seismic zones has somewhat been limited. This is due to the insufficient research data and guidelines for the seismic design of bridges using HSC and HSR and the lack of a reliable analytical model. Therefore, to address this issue and promote the application of HSR and HSC, this paper investigates high-strength bridge columns' seismic performance experimentally and numerically. Six large-scale reinforced concrete (RC) bridge columns and one multi-column bent frame were tested under a quasi-static cyclic loading with constant axial compression. The primary design parameters were axial load ratio, longitudinal and transverse reinforcement yield strength, and transverse reinforcement spacing. The failure pattern of high-strength columns was similar to conventional RC columns and satisfied the requirements for seismic design in terms of failure mode, hysteresis behavior, ductility, and energy dissipation capacity. The experimental ductility values of the high-strength columns were satisfactory and capable of meeting the ductility demand of most codes. Furthermore, a numerical model was built using the OpenSees program to predict the seismic performance of the specimens and then verified by comparing them with the test results of 12 columns. The numerical model's results were in good agreement with the experimental results. The results suggested that numerical modeling techniques commonly used for normal strength concrete (NSC) columns can be used for HSC bridge columns by incorporating a proper material model. [ABSTRACT FROM AUTHOR]

This paper presents an overview on fire behavior of bridge girders mainly including prestressed concrete (PC) bridge girders and steel bridge girders. The typical fire accidents occurred on bridges are illustrated and, the seriousness of posing threats to bridge structures resulted from increasing traffic fires, specially intense hydrocarbon fires generated from petrol-chemicals, is highlighted. The current researches, embracing high-temperature properties of constituent materials, prestress state, measurement in fire tests, numerical methods, structural fire resistance, and so forth, taken on coping with problems existing in fire behavior and structural fire behavior in bridge girders are reviewed and discussed. Further, strategies for enhancing fire resistance of bridge girders followed with failure criterion and mode in types of bridge structures are provided. Future research area along with emerging trends in structural fire behavior of bridge girders is also recommended for mitigating fire hazards occurred on bridge girders. Herein, it can be attained a conclusion from review and discussion that prestressed concrete bridge girders with thin webs, specially T-shaped bridge girder, are prone to unstable under fire exposure conditions. High-strength concrete utilized in prestressed concrete bridge girders is vulnerable to spalling at elevated temperature. Steel-truss bridge girder present a more significant fragility to fire exposure compared than other steel bridge girders. [ABSTRACT FROM AUTHOR]

Selecting fires safety measures for road tunnels relies mainly on strict regulatory requirements. However, the choice should also be based on many different criteria and ranking of alternatives should take place. Existing methods exhibit lack in dealing rigorously with measures' selection amongst different alternatives. This paper contributes to the body of knowledge by proposing a novel method, named EVADE, which aims to incorporate diverse stakeholders' views and provide a meaningful ranking of alternatives. To do so, it estimates the tunnel level of safety taking into account only any standard measures existing. Subsequently, the performance of additional measures is examined. Then, a list of the most significant criteria that are valuable to judge the appropriateness of selected measures is introduced. The relative importance amongst the decision criteria is calculated through the Analytic Hierarchy Process, based on the expert opinion. Sensitivity analysis through Monte Carlo simulation is embedded to allow for a meaningful prioritization of the decision criteria. Thus, the alternatives’ ranking comes as a distribution instead of a single number, providing the decision-maker richer information for selecting the most suitable measure(s) according to the specific tunnel situation. At last, a typical tunnel is examined to showcase the utilization of the method. [ABSTRACT FROM AUTHOR]

Due to increased demands in transportation development, bridge construction has been extended to areas with complex wind fields. In addition to common flow features such as high wind speeds and strong turbulence intensity, in coastal areas, bridges are likely to be exposed to non-stationary and non-Gaussian high-speed wind fields during hurricane events. Bridges built in mountainous regions will experience varying wind directions, incident angles of attack (AOA), and wind speed variation due to undulating terrain. The complex wind fields are challenging to the bridge engineering community to which accurate calculation methods and suppression measures for bridge vibration are urgently required. In this paper, state-of-the-art research results are introduced through three categories: (a) the distinctive characteristics of complex wind fields in offshore and mountainous areas, (b) the categories of wind-induced vibrations for bridges, and (c) the suppression measures employed in engineering practices. Until now, the studies regarding the coupled bridge vibration in complex wind fields have made considerable progress, but a richer database of actual wind measurement results and more efficient simulation methods still need to be further established. [ABSTRACT FROM AUTHOR]

The application of the neural network method in health monitoring and structural system identification has received extensive attention. A reasonable neural network structure is very important for its performance. This paper takes the pedestrian bridge of the Xingfu intersection in Urumqi, China, as the research object and uses MIDAS/Civil to establish a finite element analysis model. Taking the natural vibration frequency obtained from the dynamic test of the actual bridge as the target, two kinds of neural networks are used to predict the structural material parameters. An appropriate bridge model correction method is selected by comparing the prediction results of the BP neural network and the GRNN. The test results show that the pedestrian bridge model based on MIDAS/Civil has a high accuracy, but it still does not meet the actual needs. The modified model based on the BP neural network is close to the actual measured results, and a more accurate finite element analysis model can be established by this method, which makes the modified model closer to the real stress state of the structure. [ABSTRACT FROM AUTHOR]

Copyright of Beton- Und Stahlbetonbau is the property of Wiley-Blackwell 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.)

Copyright of Bautechnik is the property of Wiley-Blackwell 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.)

Copyright of Bautechnik is the property of Wiley-Blackwell 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.)

This paper investigates the near-fault (NF) seismic performance of a novel isolation system, referred to as the roll-n-cage (RNC) isolator, considering the cable-stayed Bill Emerson Memorial Bridge in Missouri. The RNC isolator is designed to achieve a balance in controlling bridge displacement demands, structural accelerations, and internal forces in the tower attributable to horizontal seismic forces. It provides in a single unit all the necessary functions of rigid support, horizontal flexibility with enhanced stability, and energy-dissipation characteristics. Moreover, it has two unique features that are built-in: energy-absorbing buffer and linear recentering mechanisms. Through a nonlinear time history analysis under three recorded NF earthquakes and three synthetic ground accelerations, the results show that the RNC isolator is a convenient isolation system in protecting cable-stayed bridges against NF earthquakes. [ABSTRACT FROM AUTHOR]

Everything that a term classifies should have similar features and characteristics, yet it is observed that what have been termed white elephant projects by people have very differing characteristics. This paper aims to show that there is an error constantly made in the definition of white elephant projects. It uses a literature review to establish that there are two descriptors in the term "white elephant project", which are: (i) white elephant and (ii) project; and that for anything to qualify as a white elephant project, it must meet the descriptors (i) and (ii), that is, it must be a white elephant and must also be a project. An analysis of certain undertakings that have famously been termed white elephant projects was done. The analysis revealed that not all of them met (i) and (ii). Thus, not all of them are correctly white elephant projects. Those not meeting (i) and (ii) have erroneously been called white elephant projects. This paper then proffers a correct definition for "white elephant projects". [ABSTRACT FROM AUTHOR]

In this paper, strength reduction factors (R-factors) for performance-based seismic design of bridges in far-fault seismic regions are developed. Response spectrum analyses (RSA) and nonlinear time history analyses (NTHA) of simplified bridge models with piers of circular and rectangular sections having several substructure-superstructure connections are performed for wide ranges of design parameters and pier displacement ductilities based on target performance levels are obtained. Subsequently, a set of equations representing R-factors is proposed by performing linear regression analyses on the data obtained from the analyses. The accuracy of the proposed equations is investigated by performing error performance analyses, which indicated R-factors with mean error values close to zero. Furthermore, a simple application procedure of the proposed R-factor equations is presented and explained in detail through various sample bridges designed to achieve the performance objectives recommended by AASHTO LRFD, Eurocode, and the Canadian Highway Bridge Design Code (CSA). Eventually, a comparison between the estimated R-factors and those suggested by design codes is presented. The results showed that AASHTO LRFD recommends conservative R values for single-column bents, while it provides overestimated R values for multiple-column bents. Indeed, it is found that Eurocode recommends conservative R values for piers of limited-ductile behavior and relatively high R values for piers of ductile behavior. Therefore, it is concluded that the R-factors suggested by design codes might result in performance levels not intended in design. • Strength reduction factors (R-factors) for performance-based seismic design of RC bridges is presented. • The paper presents Six R-factor equations expressed in terms of various design parameters. • A novel performance-based seismic design procedure for RC bridges is introduced. • The paper provides an assessment of the R-factors existing in design codes by comparing them with the estimated ones. • The research provide valuable information to the bridge engineering community for improving the seismic design codes. [ABSTRACT FROM AUTHOR]

Knowledge graphs (KGs) are crucial in documenting bridge maintenance expertise. However, existing KG schemas lack integration of bridge design and practical inspection insights. Meanwhile, traditional methods for node feature initialization, relying on meticulous manual encoding or word embeddings, are inadequate for real-world maintenance textual data. To address these challenges, this paper introduces a bridge maintenance-oriented KG (BMKG) schema and approaches for graph data mining, including node-layer classification and link prediction. These methods leverage large language model (LLM)-based text encoding combined with GraphSAGE, demonstrating excellent performance in semantic enrichment and KG completion on deficient BMKGs. Additionally, ablation studies reveal the superiority of the pre-trained BERT text encoder and the L2 distance pairwise scoring calculator. Furthermore, a practical implementation framework integrating these approaches is developed for routine bridge maintenance, which can facilitate various practical applications, such as maintenance planning, and has the potential to enhance the efficiency of engineers' documentation work. • This paper introduces a hierarchical knowledge graph schema based on real-world bridge maintenance reports. • A node-layer classification approach is proposed for semantic enrichment by employing GraphSAGE and LLM-based text encoding. • A link prediction approach is proposed for graph completion by leveraging GraphSAGE and contrastive learning. • An implementation framework integrating the above schema and approaches is designed for practical bridge maintenance. [ABSTRACT FROM AUTHOR]