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Raised bogs (peat moss-dominated wetlands) are under environmental pressure but valued for their specific biodiversity and climate-mitigating potential. Strong efforts to restore these unique ecosystems contrast with a limited focus on cultural heritage management in bogs, putting their exceptional cultural heritage at risk. We take a new perspective on cultural heritage management in bog remnants and make recommendations for measures synergetic to their natural and cultural heritage. We focus on tangible cultural remains on the surface of bog remnants and surrounding former bog areas in the Netherlands, where bogs have long been under exceptional use and environmental pressure. To reach this objective, we first (1) explore the range and diversity of tangible cultural remains on the land surface through analysis of three case studies, (2) conduct a systematic inventory of how such cultural remains are currently incorporated in land management in and around 17 bog remnants, and (3) based on that develop a range of recommendations for improved integral management. We illustrate how preserving and displaying cultural remains can be aligned with the achievement of ecological goals in bog nature reserves. [ABSTRACT FROM AUTHOR]

The safety and serviceability of long-span bridges can be significantly impacted by wind effects and therefore it is crucial to estimate them accurately during bridge design. This study develops full-scale three-dimensional computational fluid dynamics (CFD) simulation models to replicate wind conditions at the Rose Fitzgerald Kennedy Bridge in Ireland. The neglect of bridge geometries and the use of small scales in previous studies are significant limitations, and both the bridge geometry and surrounding terrain are included here at full scale. Input values for wind conditions are mapped from weather simulations that apply the weather research and forecasting model. Wind velocities at four different points calculated by CFD simulations are compared with corresponding data collected from structural health monitoring field measurements. The calculated time-averaged wind velocities at four different locations on the bridge are shown to have relative differences of less than 10% from the wind velocities measured by anemometers 90% of the time. The maximum relative difference among all comparisons was only 15%, shown to be partially due to the inclusion of the full bridge and terrain geometry. [ABSTRACT FROM AUTHOR]

Despite the significant advances in structural health monitoring (SHM) technology and the widespread use of monitoring in other industries, its use on bridges remains relatively limited. Bridge owners seem to consider that the cost and difficulty of installing and maintaining sensors and data acquisition equipment outweigh the potential benefits that might be gained. In addition, owners realise that monitoring and managing the data also requires resources. There is a difference in philosophy and approach when considering SHM on new complex bridges and on existing bridges. On new bridges, SHM can assist engineers validate design assumptions. On existing bridges, the use of SHM has typically been on a reactive, usually temporary basis, to address specific concerns. Some of the challenges surrounding the use of SHM, particularly on existing bridges, are examined in this paper and a new development in SHM that uses risk prioritisation as part of the wider asset management of bridges is described. [ABSTRACT FROM AUTHOR]

Recent failures of bridges worldwide highlight the need for robust structural health surveillance systems to provide alerts for early damage and prevent severe loss. Structural health monitoring (SHM) continues to evolve and gain wide adoption among asset managers to mitigate catastrophic failure risks of structural systems. With the prolific integration of SHM with artificial intelligence and internet of things systems becoming prevalent, several data-driven approaches have gained popularity in SHM. However, it is challenging to obtain ground-truth-labelled damage samples for supervised machine learning methods. A class of shallow machine learning methods known as unsupervised methods (e.g. the one-class support vector machine (OCSVM)), which only uses unlabelled data from a healthy state, has been shown to achieve promising results. However, shallow machine learning methods require laborious expert-crafted feature inputs for optimal performance. Inspired by the automatic feature-extraction ability of deep neural networks, unsupervised methods (deep learning models trained without supervisory ground truth labels) such as autoencoder (AE)-based methods were explored to detect structural damage. Results obtained on both real-world data from Sydney Harbour Bridge, one of Australia's iconic structures, and data collected from laboratory specimens demonstrate the effectiveness of the AE-based method over conventional shallow methods such as the OCSVM. [ABSTRACT FROM AUTHOR]

As bridge engineers, we reach conclusions about the safety of structures by relying on data from analytical models. How do we know that the assumptions these models are based on are correct? To answer this question, a monitoring programme using sensors was implemented during the structural assessment of a 287 m span steel tied-arch bridge on the Dutch highway network. During a full traffic closure, a predefined truck was driven across the bridge multiple times, while 89 gauges recorded strains at locations of interest on the structure. The recorded measurements were compared with the results derived from the analytical model used for the assessment. The model validation considered the structural health monitoring measurements and compared them with the response of the finite-element model under codified moving loads. The measured structural behaviour was used to calibrate the model, which ensured that the analysis and safety assessment of the bridge were based on a validated model. The use of monitoring programmes on existing structures enables the engineering community to work towards a method to capture structural behaviour more accurately without excessive effort and overly complex models. [ABSTRACT FROM AUTHOR]

Track irregularity is an important factor affecting the train-track-bridge system interaction, and for the seismic design of the track-bridge system, the study of the law of the influence of track irregularity on the train dynamic effect is of great theoretical significance. Based on this, the finite element models of China railway track structure (CRTS) II plate high-speed railway simple-supported girder bridge and CRH2C high-speed train model are developed and compared with the shaking table test results to verify their validity. Considering track irregularity and earthquake randomness, a sample library of the train dynamic effect of the track-bridge system under earthquake is established, the probabilistic statistical characteristics of the train dynamic effect are analyzed, and the influence level of track irregularity on the train dynamic effect of the track-bridge system under earthquake is studied, and the standard value of track irregularity influence coefficient of train dynamic effect based on probability guarantee rate is proposed. The results indicate that: the influence of track irregularity on the seismic response of bridge structure is slight, with their greatest impact not exceeding 1%. However, it has a significant impact on the seismic response of track structures. The standard values of the sliding and mortar layers' track irregularity influence coefficients are 1.49 and 1.71, respectively, at 0.1 g. Under various peak ground acceleration (PGA) settings, the fasteners' standard values for the track irregularity influence coefficient are less than 1.1. Additionally, the degree of influence of track irregularity on the seismic response of track structure decreases significantly as the PGA increases. [ABSTRACT FROM AUTHOR]

Concrete bridge decks are critical transportation infrastructure components where deterioration can compromise structural integrity and public safety. This study develops machine learning (ML) models using the National Bridge Inventory (NBI) to classify deck conditions and predict deterioration trajectories. Models were tested and trained on inspection records from over 28,786 bridges in Michigan over 23 years, from 1992 to 2015. Eleven approaches were evaluated after hyperparameter optimization, based on 10-fold cross-validation, including logistic regression, gradient boosting, AdaBoost, random forest, extra trees, K-nearest neighbors, naive Bayes, decision tree, LightGBM, CatBoost, and bagging. Model effectiveness was assessed using accuracy, recall, F1-score, and area under the curve. Results indicate the optimized CatBoost classifier achieved 96.66% testing accuracy in rating deck conditions. The incorporation of hyperparameter optimization has significantly enhanced the overall predictive performance of the models, ensuring robust and reliable deterioration forecasting. The research sheds light on crucial factors such as deck age, area, and average daily traffic, contributing to a more comprehensive understanding of the factors influencing bridge deck condition ratings. These insights inform preventative maintenance planning to extend service life. This work pioneers a data-driven framework to forecast concrete deterioration, empowering officials with precise predictions to optimize infrastructure management under budget constraints. The approach provides a promising decision-support tool for sustainable infrastructure. This paper explores the use of machine learning techniques for the deterioration prediction of concrete bridge decks to estimate the remaining service life of bridges. These models will contribute to the safety, efficiency, and sustainability of bridge infrastructure by providing timely information and evidence-based decision making for bridge maintenance and management. Such prediction models have several practical applications such as (1) predicting when maintenance or repairs are likely to be needed; (2) assessing the risk of failure or deterioration of different components of a bridge; (3) effectively managing the bridge life cycle by providing insights into the aging process and helping authorities plan for rehabilitation or replacement strategies; (4) enabling ongoing monitoring of the performance of a bridge under various conditions such as heavy traffic loads, environmental factors, and seismic events; and (5) assisting in effective asset management by allowing for the prioritization of investments, the efficient allocation of budgets, and the planning for the long-term sustainability of the bridge infrastructure. [ABSTRACT FROM AUTHOR]

Uncoated weathering steel (UWS) is used for bridges to minimize maintenance costs incurred due to possible steel corrosion. State highway departments often use weathering steel for bridges with the expectation that the weathering steel structure will not corrode. Weathering steel has improved corrosion-resistant behavior over conventional steel; however, weathering steel is not maintenance free and will corrode if not used in correct ambient conditions and properly maintained. Consequently, weathering steel retards corrosion but may require future restoration through cleaning and/or applying surface coatings. The Arkansas Department of Transportation (ARDOT) bridge inspection inventory includes 859 UWS bridges. Approximately 11% of these bridges have some level of oxide film degradation, AASHTO defect code 3430. These bridges are located throughout the state. Other states have also experienced this condition, resulting in state highway departments facing the dilemma of how to restore weathering steel sections that have experienced corrosion. This article reviews the extensiveness and severity of oxide film degradation at UWS bridges in Arkansas, the prevalence of UWS oxide film corrosion in other states, how oxide film corrosion progresses as a function of time, and remediation measures. [ABSTRACT FROM AUTHOR]

The assessment of existing reinforced concrete (RC) structures, especially, bridges and viaducts, nowadays is one of the most relevant aspects for infrastructural engineers. Due to the old age of a large part of the railways and roadways assets, their safety, especially, with respect to the Ultimate Limit States (ULS) may result compromised. Safety assessment can be performed following different approaches as well as the most sophisticated methodologies based on the application of safety formats for non‐linear finite element (FE) analyses. This study presents the safety assessment at the ULS of existing prestressed RC bridge decks regarding bending moment and axial force failure mechanism adopting different methodologies. Specifically, the safety assessment will be performed through five different approaches (i.e., Courbon theory, elastic FE analysis, and NLFEAs according to the three global safety formats). The decks are modeled using, first, Courbon theory and then, girder FE model composed only of beam elements. The safety assessment is performed by comparing the design resisting moment and design acting moment in the section of interest, therefore, through a local approach. Within the local approach, design values are calculated using the partial safety factors. Afterwards, the decks are modeled with a 3D non‐linear FE model. Three different global safety formats are implemented within a global approach. The application of the different approaches leads to significantly different conclusions about the safety assessment. The two local approaches are the most conservative, therefore, lead to a lower safety margin. The application of global approaches based on global safety formats leads to a safety margin gain compared to local approaches, with significant variability in terms of safety margin gain depending on the specific global safety format. [ABSTRACT FROM AUTHOR]

A lot of bridges are aging and reaching the anticipated service life. To gain insight in their remaining resistance, inspections and measurements can be performed. The resulting information and data can be used to update variables in the degradation models of these bridges. To account for spatial variation, degradation variables can be modeled with random fields. The random fields of the degradation variables are updated based on a Bayesian inference procedure, where different types of heterogenous and indirect data are accounted for. Nevertheless, in this procedure, various assumptions need to be made, such as the quantification of measurement uncertainty, the structural and degradation model to be used, the prior distributions of the variables of interest, and so forth. These assumptions can influence the results of the Bayesian inference. Hence, in this work, it will be investigated what the influence is of different assumptions and how they affect the localization and quantification of damage. This will be done by application to a reinforced concrete girder bridge. The main conclusions are that the model used in the Bayesian inference procedure should resemble the actual structure as good as possible and that simplifications that are allowed in the design can lead to posterior distributions deviating a lot from the actual situation. Moreover, it is illustrated how information from visual observations can be included in the definition of the prior distributions and how this has a beneficial effect on the posterior predictions. [ABSTRACT FROM AUTHOR]

In this study, a finite element (FE) model of an existing prestressed concrete box‐girder (PCB) bridge is developed using Abaqus/Explicit (2022), and a series of FE simulations are conducted to examine the results of composite trusses (CTs) in strengthening PCB bridges with different shapes. A concrete damage plastic model of concrete is used to predict the nonlinear behavior of concrete. Field tests and theoretical calculations are performed to verify the rationality of the model. Three CTs of different shapes, that is, a K‐shaped composite truss (KCT), an X‐shaped composite truss (XCT), and a triangle‐shaped composite truss (TCT), are used to strengthen the PCB bridge models. The deflection, load distribution, distortion, and surface connection forces under two types of lane loads (European code [EU] and Chinese code [CC]) are discussed. The results show that the CT can reduce the deflection and distortion of the PCB bridge and improve the load distribution. However, the different CT shapes offer other strengthening effects. Among them, the XCT reduces deflection the most significantly, that is, by 8.9% and 17.1% under the two load modes, separately. In addition, the XCT improves the load distribution of the PCB bridge the most significantly. The KCT reduces the distortion of the PCB bridge the most significantly and decreases the stress ratio by 75.36%. Moreover, the deflection of the PCB bridge under the EC is more significant, indicating that the lane load defined by the EC is larger than that by the CC. The maximum surface connection forces are different under the same load mode for the different CTs. However, in all the models, the bending moment at surface‐2 is insignificant. Based on the analysis results, five assumptions are introduced. Using the KCT as an example, the plane model of the reinforced section is simplified, and a canonical equation is established to calculate the load distribution factor. The 324 coefficients and 18 free terms in this canonical equation are deduced, which provides a theoretical basis for strengthening PCB bridges using CTs. [ABSTRACT FROM AUTHOR]

The long‐term behavior of slender (1/40) long‐span precast high‐strength concrete girders was experimentally investigated regarding their use as a competitive solution in relation to steel alternatives for highway overpasses. The time‐dependent effects of full‐scale girders has rarely been addressed, particularly the influence of creep and shrinkage of concrete with compressive strengths around 120 MPa. Two half‐scale girder specimens were produced using an economically optimized and high‐strength concrete mixture, nonfiber reinforced, designed only with conventional raw materials, currently available at Portuguese precast companies, and subjected to long‐term loading, with a magnitude of approximately 50% of the failure load in bending, during a period of 3.75 years. Using the same mixture, prismatic specimens were also produced and subjected to long‐term loading at 24 h and 7 days of age to assess both creep and shrinkage. Results show that the age of concrete at the loading day is of paramount importance regarding the time‐dependent effects. These are most relevant during the first days of loading and tend to stabilize from the 112th day of loading onward. The time‐dependent girder's mid‐span deflection at the end of the 3.75 years did not exceed more than 50% of the initial deformation. Comparison of results with those obtained with Model Code 2010 and the current version of Eurocode 2 shows that these underestimate strains and deflections due to creep, mostly because the short‐term development of these effects, occurring during the first days of loading, are not adequately represented. On the contrary, a sound agreement between experimental and theoretical values, both in short and long term, was obtained using the Auperin et al. approach. [ABSTRACT FROM AUTHOR]

The Isla de Arousa Bridge, 1980 m long, is the only road access to Isla de Arousa. Built in 1985, this single‐cell box girder divided into 40 spans runs entirely over the sea. In response to corrosion damage, the local government decided to make an intervention with an ambitious repair project in 2009. The repair, carried out with three different techniques, aims to collect data for future repairs. In this research the results of rehabilitation and comparison of the evolution of the repairs are described, together with the data on the progression of corrosion and its effect on the life cycle. At the moment, with data from 10 years of protection, both hybrid and galvanic anodes installation have shown effectiveness. Bridge Health index analysis shows that after reparation, the bridge presented a very good condition, and even after 10 years the condition is still good, except for some damaged bearings. [ABSTRACT FROM AUTHOR]

Several overloaded-induced overturning incidents of girder bridges with single-column piers have occurred in recent years, resulting in significant casualties and economic losses. Temperature, in addition to overloading, may also play a role in exacerbating bridge overturning. To investigate the association between temperature and bridge overturning, an explicit finite element model (EFEM) of a three-span concrete curved continuous bridge considering nonlinearities was developed to simulate overall collapse. The effects of uniform and gradient temperatures on the overall overturning stability of curved and straight bridges were evaluated based on the EFEMs. Furthermore, the temperature–bridge coupling model and temperature–vehicle–bridge coupling model were utilized to examine how gradient temperature influences bridge overturning. The results show that the overall overturning collapse of a bridge follows four stages: stabilization, transition, risk and overturning. Variations in uniform temperature from −30 °C to 60 °C had a negligible effect on the ultimate vehicle weight for bridge overturning, with a variation of less than 1%. As the gradient temperature ranged from −30 °C to 60 °C, curved bridges show less than a 2% variation in ultimate vehicle weights, compared to a range of −6.1% to 11.7% for straight bridges. The torsion caused by positive gradient temperature in curved bridges can exacerbate bridge overturning, while negative gradient temperature in straight bridges can lead the girder to 'upward warping', facilitating girder separation from bearings. Monitoring the girder rotation angle and vertical reaction force of bearings can serve as important indicators for comparing the stability of bridges. [ABSTRACT FROM AUTHOR]

Traffic load is one of the important external loads of bridges and simulating the site-specific traffic load is important for bridge condition assessment. This study proposes a new microscopic model to simulate the stochastic traffic load of any time period at bridge site based on weigh in motion (WIM) data. A model for simulating the microscopic interaction between vehicles was first proposed, by which free driving, car following and sudden braking can be reasonably simulated. Axle-weight information from the WIM data was embedded into the model to precisely simulate the vehicle load. A new vehicle sequence generation method based on WIM data was then proposed to generate the site-specific vehicle sequence of any time period with consideration of non-stationarity. Finally, a framework for simulating the site-specific stochastic traffic load is established. The proposed framework is validated through application based on realistic WIM data in traffic-flow simulation and load effect quantification. Comparisons of simulation results with the existing methods were also conducted to show the reasonability and novelty. The results indicate that the proposed framework can produce reasonable site-specific stochastic traffic load over any time period based on WIM data. [ABSTRACT FROM AUTHOR]

Bridges deteriorate due to different causes such as ageing and climatic conditions. As a consequence, repair actions are considered more expensive than maintenance. Therefore, the prediction of maintenance at the bridge network level is particularly complex due to the considerable level of heterogeneity spanning various bridge types and functions. Consequently, in this article an analytical deterioration model called 'two-step cluster analysis' is presented and applied to predict the results of a homogeneous data set. This model had been used in different fields including civil engineering but not for superstructure deterioration forecasting. Variables that interfere with the performance of the structure were considered, such as geometry, volume of traffic, among others. The results show that deterioration drop rapidly if repair treatments were not performed. Variations of up to 20.9% at 50 years between the degradation of the database and the analysis of groups, demonstrates the importance of grouping within the analysis of the database, since the late maintenance can affect the life of the bridge. Preventive actions could significantly mitigate the deterioration process. The applied methodology benefits from current bridge inspection practice and produces a probabilistic rating that is consistent with the Markov approach for model deterioration and grouping variables. [ABSTRACT FROM AUTHOR]

In recent years, the transformer has gained significant popularity due to its crucial role in various fields. This paper presents a design and modeling approach for an interleaved transformer integrated into an isolated full-bridge buck converter. The characteristics of the converter are first specified, followed by a description of the transformer to determine the geometric parameters. The technical characteristics, represented by analytical expressions, are addressed in the authorized electrical model of the integrated interleaved transformer. The simulations reveal the impact of the interleaved transformer's geometric parameters on the inductance value, quality factor, and coupling coefficient. Additionally, the simulation results demonstrate that reducing the conductor width, internal diameter, and number of turns leads to a higher quality factor. To validate the proper functioning of the interleaved transformer, simulations of the isolated full-bridge buck converter are conducted. The simulations encompass both a conventional transformer and an integrated interleaved transformer, with waveforms of currents and voltages analyzed. In both cases, the simulation results exhibit strong similarities and align with the specified requirements. [ABSTRACT FROM AUTHOR]

Molecular-level liquid bridges at contact interfaces have a much more important impact on micro-/nanosystems and flexible wearable sensors. However, their dynamic behavior and mechanical properties are still vague due to the limitations of current characterization methods. Here, under the support of molecular dynamic simulations on smooth, pillared, and concave pillared plates, the heterogeneous anisotropic pressure distribution of layered liquids is found to be distinct from the isotropic pressure distribution in the macroscale liquid bridge. Oscillating interfacial contact forces appear in the period of layered liquid compression due to the oscillating system free energy, in which the peak forces greatly increase as the number of layers decreases. The layered liquids with impressively remarkable solid-like pressure-bearing capacity at the gigapascal level and exceptional fluidity along confined atomic layers can spontaneously strengthen adhesion vertically and facilitate pressure transport horizontally, respectively. The significance of layered liquids in contact systems can improve our understanding of liquid bridges at the molecular level, which is beneficial for interfacial mechanical regulation. [ABSTRACT FROM AUTHOR]

A liquid deposited on a solid surface exhibits various wetting properties, primarily influenced by solid–liquid intermolecular interactions. Achieving a well-estimation of wetting behaviors on textured surfaces remains challenging because the influence of surface textures on intermolecular interactions is unclear. Here, an equivalent surface model is proposed to unify the wettability of both plane and textured substrates through intermolecular interactions. We show that by incorporating intermolecular interactions, lattice structures, and surface topographies, the substrate wettability can be tailored in an equivalent plane with the same average Lennard–Jones potential energy field E. The wettability of one substrate (plane or patterned) is transferred from non-wetting, partial wetting to complete wetting by adjusting the potential well depth of E, εa. With enhancing εa, complete wetting is achieved under the critical potential well depth of E, εac. Before εac, the spreading radius grows as R ∼ t1/1.47 until reaches equilibrium. In this scenario, the equilibrium contact angle θ and spreading factor β are strongly dependent on εa, and cos θ is linear to εa. When exceeding εac, complete wetting is achieved, and droplets spread with a precursor film as R ∼ t1/2.3 latterly. This model builds a bridge to link intermolecular interactions and substrate wettability normalization. This strategy offers a framework for substrate surface design and wettability manipulation, catering to applications such as photoresist-drop dispensing in nanoimprint lithography, surface design for grating antifouling, and anti-icing on aircraft surfaces. [ABSTRACT FROM AUTHOR]

Combining Unmanned Aerial Vehicles (UAVs) and close-range photogrammetry has become a safer, more efficient, and cost-effective solution for bridge inspection compared to conventional methods. However, close-range bridge images captured by UAVs often suffer from severe quality issues, such as blurriness, improper exposure, limited coverage, or insufficient resolution. These issues can adversely affect subsequent damage identification and bridge condition assessment, thereby hindering the widespread application of UAVs in bridge inspection. This paper presents a novel in-flight image quality check (IIQC) framework for rapidly assessing UAV-captured images against bridge inspection requirements. This framework incorporates (1) a new coarse-to-fine image pose estimation approach for precisely estimating the relative poses of UAV images with respect to a reference model, (2) a comprehensive set of refined image quality metrics for assessing image quality across various aspects, and (3) an Image Quality Metrics (IQM)-embedded bridge representation model for visualising the evaluation results. All components within this framework have been validated through extensive simulation and real-world experiments, encompassing various bridge structures (i.e., girder, arch, and truss bridges) and different weather conditions. The results show that: (1) the average root mean square error (RMSE) of the estimated image poses by the coarse-to-fine method across multiple structures reached 0.189 m in position and 0.203° in orientation, showcasing an improvement over 50 % than the image poses retrieved from the UAV; (2) the image quality metrics offer comprehensive insights into image blurriness probability and exposure intensity at the pixel level and can effectively identifying missing and insufficient captured areas; (3) the bridge representation model is capable of delivering valuable and user-friendly feedback of the assessment results to the pilot; (4) the IIQC framework can offer a rapid and comprehensive assessment of close-range UAV images in near real-time by leveraging an existing Building Information Model (BIM) of the target bridge, serving as a novel and efficient solution to thoroughly tackle image quality issues in UAV-enabled bridge inspection. Its versatility can potentially be extended to encompass other structural types, including buildings and dams. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore the higher-order turbulence statistics of flow and turbulent length scales around a complex pier (CP) and compare the results with those for a simple pier (SP). The velocity data were recorded in a laboratory flume using particle image velocimetry (PIV). The PIV data were analysed to estimate the velocity fluctuations of third order, turbulence production and dissipation rates, turbulent length scales and the contributions of burst–sweep events to the total Reynolds shear stress around the piers mounted on a rigid flat surface. The skewness and advection coefficients indicated a more asymmetric distribution of velocity fluctuations for the SP than for the CP. Ejection and sweep events illustrated the dominance of similar strengths for an extended period, downstream of the piers. The upstream turbulent kinetic energy production was similar for both piers, while the upstream dissipation rate was higher for the CP. The length scales were greater at the upstream for the case of the SP while, downstream, they were greater for the CP. The findings of this work demonstrate the importance of a pile cap in restricting downward-moving flow by showing a lower magnitude of scour-inducing turbulence parameters for the CP as compared with the SP. [ABSTRACT FROM AUTHOR]

Modal parameter estimation of a bridge with the vibration responses measured from an instrumented vehicle moving at a controlled speed is an active area of research. It is challenging to determine bridge natural frequencies and their associated mode shapes, as the measured output-only responses of an instrumented vehicle contain the desired dynamic responses of the bridge, along with the other confounding components related to vehicle dynamics, driving frequency component, and dynamics associated with the roughness profile of the road. These bridge responses are often masked by the dynamic responses associated with the vehicle, and road surface profile. Measurement noise components add to the existing problem of separating bridge frequency from various other said components. In this paper, an attempt has been made to extract bridge frequencies and mode shapes through the output-only responses collected from a traversing vehicle and using singular value decomposition (SVD) combined with the Teager-Kaiser energy operator (TKEO). Numerical investigations are made on the proposed SVD-TKEO-based modal identification technique in the presence of measurement noise. Parametric studies are conducted to investigate the influence of vehicle speed and road surface roughness on the quality of the identified bridge modal parameters using the proposed technique Numerical simulations carried out, show that the proposed SVD-TKEO-based algorithm performs well in identifying bridge mode shapes, even with relatively higher vehicle traveling speed, and handles even roughness of the road surface profile reasonably well. Lab-level experimental studies using vehicle bridge interaction setup, are also carried out using the SVD-based modal parameter estimation technique to explore its practical use. [ABSTRACT FROM AUTHOR]

Bridges may undergo structural vibration responses when exposed to seismic waves. An analysis of structural vibration characteristics is essential for evaluating the safety and stability of a bridge. In this paper, a signal time-frequency feature extraction method (NTFT-ESVD) integrating standard time-frequency transformation, singular value decomposition, and information entropy is proposed to analyze the vibration characteristics of structures under seismic excitation. First, the experiment simulates the response signal of the structure when exposed to seismic waves. The results of the time-frequency analysis indicate a maximum relative error of only 1% in frequency detection, and the maximum relative errors in amplitude and time parameters are 5.9% and 6%, respectively. These simulation results demonstrate the reliability of the NTFT-ESVD method in extracting the time-frequency characteristics of the signal and its suitability for analyzing the seismic response of the structure. Then, a real seismic wave event of the Su-Tong Yangtze River Bridge during the Hengchun earthquake in Taiwan (2006) is analyzed. The results show that the seismic waves only have a short-term impact on the bridge, with the maximum amplitude of the vibration response no greater than 1 cm, and the maximum vibration frequency no greater than 0.2 Hz in the three-dimensional direction, indicating that the earthquake in Hengchun will not have any serious impact on the stability and security of the Su-Tong Yangtze River Bridge. Additionally, the reliability of determining the arrival time of seismic waves by extracting the time-frequency information from structural vibration response signals is validated by comparing it with results from seismic stations (SSE/WHN/QZN) at similar epicenter distances published by the USGS. The results of the case study show that the combination of dynamic GNSS monitoring technology and time-frequency analysis can be used to analyze the impact of seismic waves on the bridge, which is of great help to the manager in assessing structural seismic damage. [ABSTRACT FROM AUTHOR]

The mountain area is faced with complex coJdjtions sucn as vertical and horizontal valleys, complex geologd topography, Vmny earthquake fault zones, high seismic intensityfriBk ecologyBkcriangeable climate. The traditional concrete bridgee heavy weilrhigh consumption of sand and gravel materials, large structural dimensions of steel box composite bridges, high steel consumption, and poor overall horizontal performance of steel plate composite beams, which are not suitable for mountain construction conditions. Thejefore, based onthe construction environment and application requirements of highway bridges in mountainous areas, the structural scheme of steeHX-steel pete composite beam is put forward in this paper, and the design 50 m landaTa-span steel box-steel plate composite beam is studied. Jrfl®iesu[ts show that the steel box-steel plate composite beam structure scheme is adopted, which has excellent mechanical characteristics of steel box girder and k simple structure of steel plate girder. It has the mechanical characteristics of balancidtransverse force and excellent longitudinal force", so it is a reasonable choice for small radius curved beam bridge in a mountainous area, so it is a reasonable choice for small radius curved beam bridge in a mountainous area. The steel box-steel plate composite beam adopts the integrated technology of manufacture, transportation and installation, which can better meet the road transport conditions in the mountain area. The longitudinal assembly of the manufacturing unit as the installation unit can ensure the rapid and high-precision installation of the construction site, and the assembly construction of the bridge in the mountain area has been realized. The technical and economic comparison shows that the mechanical performance of steel box-steel plate composite beam is similar to that of steel box beam and obviously better than that of steel plate girder. The steel consumption and construction period of steel box- steel plate composite beam are similar to that of steel plate girder, and are significantly less than that of the steel box girder. Therefore, the steel box- steel plate composite beam is a good choice for mountain bridge construction. [ABSTRACT FROM AUTHOR]

Information access has been one of the main concerns of lexicography since the first dictionaries were compiled. This paper draws an explicit link between the proposals made from the fields of applied linguistics and website accessibility to enhance the users' experience in consulting online dictionaries. The paper starts with a reflection on two intertwined notions that are relevant for the discussion: Access and accessibility. After that, it focuses on elements connected to two Web Content Accessibility Guidelines principles, namely perceivability and understandability. It reflects on real practices regarding the way in which information is structured in today's dictionaries, the use of text alternatives, typographic choice, the writing of definitions, and the use of abbreviations, and proposes measures to tackle the identified challenges. The implementation of easy-to-understand language is highlighted as a relevant resource for prospective lexicographic projects. [ABSTRACT FROM AUTHOR]

Studies on the central and bilateral bridges of interior permanent magnet (IPM) motors often focus on individual mechanical strength or electromagnetic performance, lacking comparative studies on the electromagnetic performance of motors with different central and bilateral bridges under the same mechanical strength. This paper designs three rotors with different central and bilateral bridges and compares the electromagnetic performance of the three motors. First, to ensure the safe operation of the three rotors at high speeds, the mechanical stress of each rotor has been analyzed using the finite-element method (FEM). Subsequently, the major electromagnetic performances of the three motors are analyzed and compared, including the air-gap flux density, back electromotive force (back-EMF), inductance, salience, torque, power, loss, efficiency, and demagnetization. The results indicate that the rotor without central bridges has the largest leakage flux and the lowest torque but exhibits minimal torque ripple. The rotor with narrower bilateral bridges has the highest torque and maximum torque ripple. The torque performance of the rotor with wider bilateral bridges lies between the two aforementioned motors, and it possesses the highest efficiency. In the end, by adjusting the dimensions of the permanent magnets, the torque of all three models increases, but the motor with narrower bilateral bridges still has the largest torque. These findings provide valuable references for rotor design. [ABSTRACT FROM AUTHOR]

Integration of HGIS (Historical Geographic Information Systems) and HBIM (Heritage Building Information Modelling) constitutes a high-precision, efficient, and sustainable method for conserving cultural heritage (CH), particularly in instances characterized by large-scale distribution and spanning multiple historical periods, with extensive archival material. HBIM not only aids in the preservation of remaining structures but also facilitates the revelation and reconstruction of invisible elements. The Chinese Eastern Railway (CER), a key industrial and linear cultural heritage site in northeast China, has a variety of metal bridge heritage, many of which are documented and seen solely in historical archives until now. These bridges, designed and constructed by Russians at the outset of the 20th century, serve as crucial components of the CH along the CER while also showcasing the technological advancements and application developments in metal structures along the railway. We propose a method of integrating HGIS/HBIM to conserve the integrity of the heritage and this methodology has been validated through two case studies. A historical database was established for collection and exhibition archives in QGIS®. Concurrently, Autodesk® Revit was employed to reconstruct bridge models, incorporating material information and GPS coordinates based on the Industry Foundation Classes (IFC). Subsequently, we utilized FME® Workbench to bridge the gap between BIM and GIS. This approach promises to enhance the richness and integrity of the CH along the CER, offering a sustainable solution for its preservation and management. [ABSTRACT FROM AUTHOR]

Bridges are a critical element of the transport network. In case of neglected maintenance, war conflict or natural disaster, they may be damaged or destroyed. An alternative solution in the form of a detour is mostly feasible only in the case of ground communication. But even in this case, it can be a very difficult and lengthy solution. Therefore, temporary bridges are often used to replace the permanent bridge structure for a certain time. The history of temporary bridges is essentially as old as that of permanent bridges. The first patented temporary bridge was the Eifel Bridge, which had a span of up to 60.0 m in 1888. Before the Second World War, the most widespread structures were the German S-bridge with spans of up to 15.0 m, Herbert-brücke with a span of up to 25.0 m and the English Bailey bridge system. In the post-war era, the ŽM 60 temporary bridge was designed as a universal bridge structure, which was to serve to temporarily bridge obstacles of medium and long spans. As standard, it was to serve as a railway bridge with a span of up to 60.0 m and as a road bridge with a span of 84.0 m. The task of the study published in this paper is to approach the possibilities of deploying the ŽM 60 bridge at present in compliance with the requirements arising from currently applicable standards and regulations. [ABSTRACT FROM AUTHOR]

In this article, the authors explore examples of preserved cultural heritage related to traffic structures, focusing on the world's oldest bridges in Europe and Slovakia, as well as the oldest preserved roadways. They delve into the detailed history of Marians Square in Žilina, particularly its surface treatment, drawing from credible historical sources. The article also presents comparisons of elasticity modules and deformations of the roadway, based on measurements taken in 1966 and the last reconstruction from 1995 to 1997, which cost SK 64.5 million (equivalent to EUR 6.9 million in 2024). Through an evaluation of mechanical characteristics and environmental criteria, the authors conclude that the reconstructed road, even in 2024, effectively protects against frost damage, minimizes particulate matter and noise pollution (excluded motor traffic), and adheres to principles of contextual design for pavements. [ABSTRACT FROM AUTHOR]

This study emphasizes the significance of people management and strategic human resource management (SHRM) in shaping dynamic capabilities to promote organizational performance and sustained competitive advantage. Data for this research were gathered from 548 respondents from the banking sector in India. Covariance-based structural equation modeling was utilized for hypotheses testing. This study contributes to bridging the "black box" between high-performance work system (HPWS) and its outcomes. The research utilizes the ability–motivation–opportunity framework to formulate the HPWS bundle and confirms that HPWS is a crucial enabler of organizational agility, allowing banking organizations to adjust quickly to market needs. By using the dynamic capability view, this research considers organizational agility as a critical dynamic capability to elucidate the mechanism by which HPWS is linked to organizational performance. Furthermore, this work attempts to bring management and leadership literature closer by investigating the moderation effect of transformational leadership. The findings indicate that a higher degree of transformational leadership is essential to promote the positive association between HPWS and organizational agility. Transformational leadership can help in implementing HPWS to manage workforce adaptability, which enables the workforce to react according to the dynamic environment. Additionally, the study empirically validates that in the presence of a greater level of HR flexibility, HPWS is significantly effective in promoting agility in banking firms. [ABSTRACT FROM AUTHOR]

Scour around bridges present a severe threat to the stability of railroad and highway bridges. Scour needs to be monitored to prevent the bridges from becoming damaged. This research studies the feasibility of using green laser for monitoring the scour around candidate railroad and highway bridges. The laboratory experiments that provided the basis for using green laser for underwater mapping are also discussed. The results of the laboratory and field experiments demonstrate the feasibility of using green laser for underwater infrastructure monitoring with limitations on the turbidity of water that affects the penetrability of the laser. This method can be used for scour monitoring around offshore structures in shallow water as well as corrosion monitoring of bridges. [ABSTRACT FROM AUTHOR]

The Bridges Conference has been running on an annual basis since 1998 and is the foremost international conference dedicated to connections between mathematics and the arts, design and culture. In 2023, Bridges took place at Dalhousie University in Halifax, Nova Scotia, Canada. The conference ran from July 27 to 31, and was packed with a wide variety of plenary and contributed lectures, workshops, exhibitions, performances and public events. This article reports on the scientific, artistic and cultural programme and experience, from the viewpoint of a participant who is an academic mathematician based in Ireland. [ABSTRACT FROM AUTHOR]

The reasonable expression of live load and its accuracy are important to the safety and design rationality of highway bridge structures. In this study, the optimization issue of the traffic load model for the suspenders of large-scale suspension bridges is studied. Taking a 2300-m main span suspension bridge as an example, a method for suspender classification based on the geometric feature of the influence lines is proposed, and the extreme traffic load effect scenarios are analyzed and used as an optimization reference. Multi-objective optimization based on a genetic algorithm is used to explore the improvement of the traffic load model of the suspender. The traffic load model of the suspender is optimized with three objectives, i.e., accuracy, convenience, and improvement, and the optimization results regarding the load value and loading length are obtained. The value of the uniformly distributed load of the optimized model ranges from 6.4 kN/m to 8.9 kN/m, and the maximum value of the concentrated force could reach 1433 kN. By comparing the obtained optimized model with the current specification model and the extreme load effect scenario model, the improved applicability of the optimized model in the analysis of the load effect of the suspender can be verified. The optimized method and relevant conclusions can provide useful references for the improved design and operation management of similar bridge structures. [ABSTRACT FROM AUTHOR]

Bridge cable is an important force transmission component of bridge, but it is easy to be damaged during service, such as fatigue damage and corrosion damage, which seriously threatens the safety of bridge structure. Therefore, it is necessary to identify damage of cable force. Generally, the damage of cable force can be identified by the change of cable frequency. This paper establishes a cable force damage identification model based on Bayesian inference and uses Metropolis‐Hastings (MH) algorithm to solve the posterior probability function of unknown parameter. In the Bayesian inference model, the influence of the priori function of unknown parameters on the posterior probability distribution model is discussed. In the MH algorithm, the influence of different proposed distributions (Normal distribution, Gamma distribution and Weibull distribution) on the sampling results is discussed based on three numerical simulation studies, and the influence of burned sample proportion on the establishment of a posteriori distribution function is analyzed. Furthermore, the influence of monitoring noise data and missing data on cable force damage identification is considered, and the robustness of the proposed method is analyzed. [ABSTRACT FROM AUTHOR]

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Modern bridge construction towards a higher degree of low carbonization and assembly has been the general trend, while developing and broadening the low-carbon and assembled-oriented Accelerated Bridge Construction (ABC) technology can better realize the trade-offs between construction quality, efficiency, cost and sustainability. In the current mainstream ABC technologies such as precast-assembled concrete bridge and assembled steel bridge schemes, it is difficult to achieve an excellent balance between the above multicriterion trade-offs. To this end, this paper proposes a novel low-carbon and assembled composite bridge scheme as an innovative case of ABC technology based on a 26.7 km-length urban viaduct project in China with urgent environmental protection and assembly demands. Construction sustainability, the comprehensive economy and low-carbon performance are well balanced by the collaborative application of new steel–concrete composite structures, the rapid assembly interface design and low-carbon material technologies. The proposed scheme has been applied to a completed real-scale bridge, and the whole construction process only experienced 105 days of effective time, accompanied with slight environmental interference and construction noise and a small amount of labor and equipment input. In addition, the safety of the bridge, the rationality of the design concept and the calculation method have been verified by the static and dynamic loading tests of the real-scale bridge. [ABSTRACT FROM AUTHOR]

Bridges are one of the most critical and costly structures on road networks. Thus, their integrity and operation must be preserved to prevent safety concerns and connectivity losses after seismic events. Recent large-magnitude earthquakes have revealed a series of vulnerabilities in multi-span highway bridges. In particular, skewed bridges have been severely damaged due to their susceptibility to developing excessive in-plane deck rotations and span unseating. Although seismic design codes have been updated to prescribe larger seating lengths and have incorporated unseating prevention devices, such as shear keys and cable restrainers, research on the seismic performance of skewed bridges with passive energy-dissipation devices is still limited. Therefore, this study focuses on assessing the effectiveness of implementing hysteretic dampers on skewed bridges. With that aim, dampers with and without recentering capabilities are designed and incorporated in representative Chilean skewed bridges to assess their contribution to seismic performance. Three-dimensional nonlinear finite element models, multiple-stripe analysis, and fragility curves are utilized to achieve this objective. The results show that incorporating bidirectional dampers can effectively improve the seismic performance of skewed bridges at different hazard levels by limiting in-plane deck rotations independently of their skew angle. Additionally, the influence of external shear keys and damper hysteretic behavior is analyzed, showing that these parameters have a low influence on bridge performance when bidirectional dampers are incorporated. [ABSTRACT FROM AUTHOR]

A novel approach for analyzing coupled vibrations between vehicles and bridges is presented, taking into account spatiotemporal effects and mechanical phenomena resulting fromvehicle braking. Efficient modeling and solution of bridge vibrations induced by vehicle deceleration are realized using this method. The method's validity and reliability are substantiated through numerical examples. A simply supported beam bridge with a corrugated steel web is taken as an example and the effects of parameters such as the initial vehicle speed, braking acceleration, braking location, and road surface roughness on the mid-span displacement and impact factor of the bridge are analyzed. The results show that vehicle braking significantly amplifies mid-span displacement and impact factor responses in comparison to uniform vehicular motion across the bridge. Notably, the influence of wheel-to-bridge friction forces is of particular significance and cannot be overlooked. When the vehicle initiates braking near the middle of the span, both the mid-span displacement and impact factor of the bridge exhibit substantial increases, further escalating with higher braking acceleration. Under favorable road surface conditions, the midspan displacement and the impact factor during vehicle braking may exceed the design values stipulated by codes. It is important to note that road surface roughness exerts a more pronounced effect on the impact factor of the bridge in comparison to the effects of vehicle braking. [ABSTRACT FROM AUTHOR]

The assessment of bridge settlements is a challenging and significant problem. Moreover, aging of highway bridges is a growing concern in the US, especially when continuous monitoring is lacking. To facilitate expedient monitoring of bridges, this paper presents a projected laser system (PLS) method for monitoring that can autonomously measure and remotely report relative vertical settlements of bridges. The method uses a vision-based measurement system involving the projection of a laser pattern from a laser unit to a target unit. A cost-effective prototype implementing the PLS method was built using low-cost electronic hardware parts. The prototype of the proposed embedded system design was shown to have sub-millimeter accuracy in a laboratory experiment, and was deployed in the field to monitor a pedestrian–vehicle bridge to evaluate its overall performance. [ABSTRACT FROM AUTHOR]

This paper includes a review of the several calculation methods available to calculate the modal damping ratio from dynamic events obtained in structural health monitoring of bridges. A comparative analysis among methods involving the logarithmic decrement, bandwidth applied over the spectrum, adjustment to the theoretical curve and random decrement technique is included. Additionally, an alternative calculation method based on signal spectra reduction has been formulated, whose main advantage lies in the fact that it directly allows the study of multiple-degrees-of-freedom systems, which describe typical structures, without the need for applying filters; this method gives extremely precise values despite simplification of the calculations. First, a comparative analysis is carried out on a set of theoretically simulated waves. In these cases, although there are differences in detail, the obtained results are reasonably close to the theoretical values. Second, an analysis of the registered accelerograms during a test campaign of a real structure, the viaduct "The Arches of Alconétar", is performed. It has been observed that in this case, unlike what happens with the theoretical simulations, the obtained results significantly vary depending on the selected calculation method. For this reason, it is important to know which method has been used to calculate the modal damping ratio in structural health monitoring systems, as well as to be cautious in setting thresholds. [ABSTRACT FROM AUTHOR]

A significant number of wind bracings in existing railway transom top bridges are numerically assessed deficient against the assessment nosing load recommended by the AS5100, where in almost all cases, there is no observed evidence of wind bracings being overloaded. This paper estimates the nosing load applied by various trains to a couple of random spans of an existing railway transom top bridge. Firstly, field testing of this bridge is conducted and the measured stresses at the mid-center of girders and wind bracings are collected during various normal train operations to validate the developed Finite Element (FE) models of this bridge. Then, the nosing loads due to different trains are estimated using the validated FE model through a two-staged validation approach, including automatic FE stress intensity optimization and rigorous manual FE model sensitivity analysis while transoms in various conditions are also incorporated in the FE model. Results demonstrate that the nosing load is significantly less than the required load in the AS5100 with magnitudes ranging between 8.6% to 9.4% of the maximum vertical axle load of the passed trains; suggesting that the AS5100 assessment nosing load should be revised to avoid unnecessary expensive upgrades of numerically assessed deficient wind bracings. [ABSTRACT FROM AUTHOR]

Owing to undesired hydraulic effects, bridge collapse accidents have become increasingly frequent during the flooding season. Considering hydraulic effects in bridge design is paramount to controlling and mitigating hydrological damage. Despite the efforts in previous studies on bridges under floods, a proper partial factor of hydraulic effects considering foundation scour is still lacking for bridge design against floods. To bridge the gap, this study proposed an inverse reliability analysis framework to generate a proper partial factor of hydraulic effects and a corresponding partial factor of resistance. First, failure modes of typical short- to medium-span bridges were summarized to construct limit state functions. Then, an inverse reliability analysis framework considering hydraulic effects was proposed. The optimum partial factors of hydraulic effects and corresponding partial factors of resistance were calculated for various design specifications. Finally, a classification early warning system of foundation scour was built to forecast hydraulic failure accurately. This paper reveals the necessity of considering the hydraulic effects of floods in bridge design. The proposed framework and warning system can effectively enhance bridge safety against floods. [ABSTRACT FROM AUTHOR]

This study proposes an efficient biobjective cable force optimization strategy for concrete cable-stayed bridges aiming to maximize the safety of the structure under both the serviceability and ultimate limit state required by the design specifications. The multitude of potential load cases within limit states renders cable force optimization approaches challenged to fully satisfy code requirements, leading to encumbered complexity and computational expense. The proposed method utilized a load decoupling approach to separate the effects induced by the cable forces from other load effects to overcome this shortcoming. Furthermore, the relationship between the structural responses and cable forces was established explicitly using the influence matrix method, which aims to eliminate the finite-element method-based structural analysis in the iterations. A practical concrete cable-stayed bridge was utilized to examine the performance of the proposed method. The Pareto optimal fronts yielded by four different multiobjective optimization algorithms show a good agreement with each other, and all the computational time costs by them are less than 50 s for each run. The comparative analysis of different cable stretching plans demonstrates that optimizing the initial stretching cable forces and the final cable forces under the bridge finished state simultaneously can significantly improve the safety of cable-stayed bridges. The results also illustrate that the proposed strategy is a high-efficiency and specification-oriented cable force optimization solution for short-to-medium concrete cable-stayed bridges. [ABSTRACT FROM AUTHOR]

The experimental performance and numerical analysis of a hybrid two-column bridge bent was examined to evaluate its ability to self-center and dissipate hysteretic energy during earthquakes. The experiment was conducted using quasi-static cyclic loads on a scaled specimen with posttensioning bars for self-centering and stretch length anchors for hysteretic energy dissipation. Posttensioning bars were used to connect the cap beam, columns, and footings without any mild steel reinforcing bars crossing the cap beam-to-column and column-to-footing interfaces. The number of posttensioning bars and initial posttensioning forces and the number of stretch length anchors were determined using mechanics and equivalent design of reinforced concrete columns. No yielding of posttensioning bars, mild steel reinforcing bars, or steel spirals was observed up to a 3.5% drift ratio; yielding occurred only in the stretch length anchors that are replaceable after an earthquake. Several stretch length anchors experienced tensile elongation, which exceeded their diameter. The residual drift of the hybrid bridge bent remained below 0.5% at the maximum applied 3.5% drift ratio without any visible damage to the concrete, steel collars, or steel chairs. A nonlinear numerical model was developed to represent the hysteretic response of the rocking bridge bent and was compared with the experimental results showing acceptable global and local response. The experiment and the nonlinear numerical model demonstrate that the bridge bent remains serviceable after significant drift cycles without any damage requiring repairs, which improves seismic resilience. [ABSTRACT FROM AUTHOR]