Durable highway bridges are required to achieve long service lives with minimal maintenance, particularly where access for inspection and repair is difficult or disruptive. While previous life-cycle cost (LCC) studies indicate that stainless steel can provide long-term economic benefits, the influence of bridge location, maintenance constraints and extended service lives remains insufficiently defined. This paper presents a comparative LCC assessment of a typical highway bridge with main girders fabricated in painted carbon steel, weathering steel and duplex stainless steel. Construction and maintenance costs are evaluated over service lives of 60 years and 120 years for four representative locations using updated UK-based cost and deterioration data. The results show that although duplex stainless steel bridges have higher initial construction costs, these can be offset over the service life by eliminating periodic steelwork repainting. This is particularly the case for bridges spanning over a railway, for which the cost associated with having to close the rail network for maintenance is particularly high. Weathering steel was found to be the most cost-effective solution where environmental conditions permit; however, its use is generally considered unsuitable for coastal environments or where exposure to de-icing salts occurs.
Existing approaches for analysing vehicle-modulus bridge expansion joint () systems either neglect bidirectional interaction or incur high computational costs, thus limiting their application in practical engineering. To address these limitations, a novel iterative framework was developed to decouple the system. Based on the geometric characteristics of the MBEJ, a road roughness profile was generated as input for vehicle dynamic analysis. The resulting vehicle responses were then applied to the system to determine the centre beam vibrations, which were iteratively superimposed onto the road profile until convergence. The proposed framework was validated, and the results demonstrate that, for the 33 t three-axle heavy-duty truck analysed, rear axles induce significantly larger beam vibrations than front axles, with outer-lane vehicles causing greater vibrations than inner-lane ones. Beam vibrations are strongly influenced by vehicle speed and axle configuration and exhibit an inverse correlation with joint gap width. The dynamic amplification factor for rear axles exceeds that of front axles, decreasing with speed but increasing with gap width. By efficiently capturing bidirectional interactions, this framework offers a practical tool for optimising and bridge design.
Magnetic levitation (maglev) track plays an important role in the breakthrough of superhigh-speed transportation, but it requires extremely high track smoothness. In the long-term operation of the maglev track-bridge system, pier settlement is inevitable, causing track deformations and even leading to damage problems. In this work, a simplified model is constructed to characterise the interaction between F-rail, I-shaped steel sleeper, track bearing and U-shaped beam in a maglev track-bridge system, where the Bernoulli-Euler beam and double-beam elements with coordinate transformations are applied and springs are used to depict the substructural element coupling. A static mapping analysis method is presented to clarify the influence of pier settlement on track deformation, strain, substructural interaction forces and so on. The correctness of this model is validated by comparing it to a solid model created using Abaqus software. The influence of pier settlement, stiffness degradation and bolt fracture on track-bridge deformation and interaction is analysed in detail.
The use of segment transition in bridges (e.g. link slab bridge) is common bridge construction practice. However, state-of-the-art researches concerning link slab bridges are somewhat inconsistent. This may stem from the fact that these analyses primarily rely on the conventional finite-element method (), which is based on continuum mechanics. Continuum mechanics is known to have deficiency in handling problems with cracking and fracture phenomena; cracking is common in the case of link slab bridges. This calls for a more advanced simulation method for the link slab bridge. The applied element method () is an ideal candidate. This paper presents an formulation with a new kinematic coupling approach. This is motivated from the observation that in link slab bridges there may be kinematic constraints for some regions. The proposed method is described in detail, including basic concepts of and modifications of the system-level stiffness matrix due to the kinematic constraint. Several validation examples are then presented. These validations demonstrate the accuracy of the proposed method. Finally, a comparison with the highlights the benefit of the proposed methodology. Hence it is expected to contribute to the analysis and design of link slab bridges.
The dynamic amplification factor (DAF) is a key parameter for evaluating the dynamic performance of bridges under vehicular loading. Although it has been extensively studied, accurately determining DAF remains challenging due to the combined influence of multiple parameters and the absence of a unified evaluation methodology. In this study, the concept of DAF is revisited, and a new definition based on dynamic displacement difference is proposed to better capture the physical mechanisms governing bridge dynamic responses. A review of existing DAF definitions, calculation methods and design code provisions is first presented. Subsequently, a vehicle-bridge interaction framework is adopted to investigate the dynamic responses of a multi-span simply supported bridge subjected to different vehicle models. Numerical simulations are conducted to evaluate the sensitivity of bridge responses and DAF values to vehicle modelling assumptions and road roughness effects. The results indicate that conventional DAF definitions may overestimate or underestimate dynamic effects under certain conditions, whereas the proposed DAF formulation provides a more consistent and physically meaningful representation of dynamic amplification. This study clarifies the effects of vehicle modelling assumptions and road roughness on DAF evaluation and provides a rational basis for improving DAF assessment in bridge design and analysis.
It is necessary to accurately analyse the deformation effects of steel tube arches under construction in Tibet's high-altitude regions, where significant diurnal temperature variations and intense solar radiation prevail. Numerical simulation analysis on the sectional temperature field of the steel tube arch is carried out based on the modified American Society of Heating, Refrigerating and Air-Conditioning Engineers model. The experimental research is conducted by arranging temperature measurement points on the section of the steel arch ribs. The research shows that the temperature distribution of steel tube arches under solar radiation exhibits distinct spatiotemporal non-linear characteristics both in the transverse and longitudinal directions of the structure. Based on experimental results and finite-element analysis, the sectional temperature gradient curve for dumbbell-shaped arch ribs in the Tibet region is obtained. The dumbbell-shaped steel tube arch exhibits a temperature distribution pattern where the temperature decreases gradually from the upper tube to the lower tube and then to the web under solar radiation. The deviation between the temperature of the steel tube arch and the environmental temperature is quantified by introducing an uneven temperature coefficient.
This study introduces a novel, modular approach for the flexural strengthening of large-span prestressed reinforced concrete (PRC) I-beams using segmented precast layers of ultra-high-performance concrete (UHPC) reinforced with glass fibre reinforced polymer (GFRP) bars. This methodology addresses key constructability challenges associated with continuous, in situ strengthening of long bridge girders. The primary aim was to evaluate the effectiveness of this segmentation by considering parameters such as layer continuity and reinforcement overlap. Experimental findings from seven PRC beams demonstrated exceptional structural performance. The external precast UHPC layers yielded a substantial enhancement in load-carrying capacity (82%–112%) and initial stiffness (49%–61%). While the introduction of a joint caused only a marginal load reduction (4%–14%), it crucially provided a mechanism for controlled failure localisation, acting effectively as a plastic hinge. Furthermore, the study confirmed excellent bond integrity between the UHPC overlay and the concrete substrate, with no observed separation. These results validate the segmented precast UHPC overlay as a highly viable, efficient, accelerated and economically advantageous solution for the rehabilitation and performance upgrade of large-span structural members.
Sustainable construction aims to reduce the impact on the environment in construction processes, and civil engineers have an important role in achieving it. A key aspect of this is reducing the embodied carbon dioxide emissions in construction. Studies have shown that structural engineers design to a maximum utilisation of 80% and an average utilisation of 60%. One of the ways bridge engineers can achieve sustainable construction is by designing bridges closer to 100% utilisation of the available design standards, which will minimise the impact on the environment by using less materials. However, this rarely happens on projects for a variety of reasons that are not solely within the control of designers, and wider collaboration across client, contractor, designer and checker is required to enable it. This paper highlights the industry-wide challenges and considerations to be accounted for when designing for high utilisations and proposes solutions. The aim is firstly to equip designers with the knowledge to eliminate or mitigate potential risks on designing 100% utilisation; and secondly, to provide a framework amending procurement processes and contracts to ensure all designers tendering for work will aim to achieve a similar level of utilisation in their designs, levelling the playing field and maximising the design value.
Fibre-reinforced polymers (FRPs) have been thoroughly researched for their effectiveness in repairing and enhancing the flexural capacity of reinforced concrete (RC) beams. This paper seeks to introduce an optimised reliability-based design of a strengthened RC beam with spiral FRP. The critical cross-section of the beam is analysed in accordance with British Standard 8110 to satisfy the strain compatibility conditions. Based on this analysis, the relationship between the moment capacity and beam curvature is established. Furthermore, the influence of the FRP wrapping angle on the beam curvature is determined for both the horizontal and vertical faces. A parametric study is executed, considering different design parameters for the strengthened RC beam. It is concluded that the best achievable wrapping angles on the vertical and horizontal faces of the beam within the feasible design domain are 50 degrees, 48 degrees and 12 degrees and the best achievable thickness-width ratios within the feasible design domain for the FRP strip are 0.0042, 0.0022 and 0.0012 when the moduli of elasticity are 75 GPa, 138 GPa and 200 GPa, respectively.
Sensor layout must be evaluated to enable the capture of adequate information for integrity analysis, while keeping sensor numbers as small as possible. The research challenge of this case study of two long-span cable-stayed bridges is to optimise monitored sections, sensor placement, sampling frequency and type selection. The structural features and their structural health monitoring (SHM) systems are introduced for the two bridges. Next, the critical sections (i.e., maximum sagging, hogging girder and tower sections) are determined through finite-element modelling. Data features and patterns of thermal sensors, anemometers and deflection sensors are analysed to give feedback to the SHM design. The novel contribution of this study includes various findings: monitoring temperature gradients along the thickness of girder soffits, deck chords, girder bottom chords and cable sections is a low priority as they are small in magnitude. For temperature data, 10 min readings to obtain a datum are adequate for further analysis. Anemometers with a minimum frequency of 10 Hz are recommended at two critical locations: deck level and tower top level. Global positioning is advised to monitor large girder deflections with a minimum frequency of 1 Hz. The connected pipe system is recommended for those bridges with relatively small deflection amplitudes.
The effect that a splitter plate placed in the wake behind a bluff body has on the vortex-induced vibrations (VIV) is well recognised in the literature. This study explores whether similar effects are caused by long cantilevered extensions found on some bridge decks. The analysis employs two-dimensional Reynolds-averaged Navier-Stokes equations, prescribed motion computational fluid dynamics simulations coupled with the energy balance approach to investigate the VIV response of a set of bridge decks with varying overhang lengths. It was found that with increasing overhang length, the displacement amplitude due to vortex shedding drastically decreased. The studied deck sections exhibited a reduction of 75% in the maximum displacement amplitude when compared to the section without the overhang. A similar decrease was observed in the lock-in region width. For the sections with longer overhangs, oscillations in the wake characteristic of motion-induced vortices have been observed. These oscillations occurred at larger displacement amplitudes than those related to Karman vortex shedding by a factor of 4.5 and occurred only after an initial sustained perturbation in the displacement amplitude. Finally, the sections with longer overhangs displayed higher susceptibility to the changing Scruton number, highlighting the importance of modelling the correct damping level when committing to wind tunnel tests.
Predictive maintenance is a strategy aimed at anticipating asset deterioration by forecasting future condition, enabling proactive maintenance scheduling. Advanced analytics and machine learning allow for the identification of patterns in historical data, leading to more accurate forecasts and better-informed maintenance planning. In civil engineering, this approach is particularly relevant for managing complex assets such as bridge structures. This article presents a study on 24 517 bridges in Spain's national highway network, managed by the Directorate-General for Highways under the Ministry of Transport and Sustainable Mobility. The objective was to model the evolution of the condition index (CI) over time. Historical inspection data were combined with traffic volumes, climate variables and geotechnical characteristics. Due to the absence of key variables such as the year of construction and maintenance history, the deterioration rate between inspections was modelled first and subsequently used to forecast future CI values. An iterative process was used to develop a predictive model with gradient boosting algorithms. The model improved the error metric by 40% compared to a na & iuml;ve baseline and provided a continuous estimate of structural condition. This data-driven approach supports more efficient bridge management by optimising maintenance planning and identifying anomalies in inspection data.
The travelling wave effect has a significant impact on the seismic performance of long-span bridges. For investigation of the travelling wave impact on the seismic response of simply supported girder bridges, a five-span girder bridge with friction pendulum systems (FPS) was used as a study case. Finite-element analysis was carried out to account for the collision effect of the main girder and the dynamic response of the bridge structure. Effects of the travelling wave of seismic excitations were simulated through the absolute displacement input method. Simulation results show that the effect of travelling waves is more pronounced than those of uniform excitations on the bridge main girder and the bottom of the pier. The collision force between main beams significantly increases when the travelling wave effect was considered, and the collision force needs to be fully considered for the seismic design of large-span simply supported girder bridges. As the wave velocity increases, the beam displacement, the shear force at the pier bottom and the bending moment also increase. The overall response amplitude gradually converges to that of a uniform seismic excitation, whereas the pier top displacement and the inter-girder collision force show a declining or gradually shifting pattern.
In bridge dynamics the current practice is time domain analyses; consequently, there are specific requirements on load model formulation as well as computational intensity. This paper explores a spectral approach to evaluate bridge deck acceleration using an envelope spectrum as a moving correlated load, allowing evaluation for an ensemble of model trains rather than the traditional individual ones. Effects of bridge deck load distribution and of track defects and vehicle imperfections are included. Two loads are used as examples, the existing Eurocode high speed load model (HSLM)-A model load as well as a broad-band load in terms of a white noise. The method is applied on two bridge types, simply supported structures and short-span integral portal frames where the effect of soil–structure interaction is included. The results demonstrate that using an envelope load spectrum has potential to estimate the bridge deck acceleration levels of ordinary structures using a reduced number of simulations. In addition, it offers a potential to use spectral densities in model load development and use of measured data from real traffic. Further simplification shows that for ordinary short-span bridges, at a given damping ratio and at a given acceleration level, an approximate modal mass can be estimated.
The increasing demand for new bridges highlights the need to digitalise bridge design and construction. In addition to the fragmented nature of the detailed design stage, where separate workflows are done for geometric modelling and finite-element analysis, the existing methods often require recreating complex bridge components from scratch due to limited interoperability and a lack of reusable parametric templates. This study presents a streamlined workflow that incorporates existing software tools such as Rhino.Inside.Revit and the SOFiSTiK–Rhinoceros interface. The proposed workflow uses Revit families of bridge components as input to simultaneously create geometric and analytical models, while maintaining the parametric control within the Revit environment. A comparative analysis with other parametric cross-section modelling methods, such as Grasshopper scripting and JavaScript object notation (JSON)-based definition, shows that only the proposed workflow supports parametricity within building information modelling (BIM) and allows for multiple configurations with lower technical barriers for use. While offering a methodological advancement for researchers by bridging parametric modelling and structural analysis within a BIM environment, the proposed workflow offers practical benefits to the practitioners, including enhanced efficiency, design reuse and improved coordination during detailed design. This approach aligns with the broader goals of digital transformation in infrastructure.
Bridges are one of the key components of the transportation network infrastructure. Constructing bridges requires a large investment. To this end, identification of effective parameters in urban bridge maintenance plays an important role. Hence, the present study aims to prioritise these parameters in metropolitan Tehran, Iran. For this purpose, fuzzy decision making methods were used in the following phases: (i) data analysis to evaluate research indicators; (ii) evaluation of descriptive statistics parameters in factors analysis; (iii) monitoring and screening factors; and (iv) prioritising factors. The statistical population was estimated to be 200 people and Morgan's table was used to determine the sample size; the minimum sample size was calculated to be 127 (S = 127) and questionnaires were given to 127 experts. The results provided six main factors: structural indicators (reliability = 0.84, validity = 0.64), climate and hydrology (reliability = 0.89, validity = 0.51), safety (reliability = 0.94, validity = 0.62), strategic (regional) importance (reliability = 0.62, validity = 0.94), budget (reliability = 0.88, validity = 0.66) and traffic and paving (reliability = 0.87, validity = 0.52). Based on the results, three factors with a higher rank related to each of the main indicators were prioritised. The results can be used to determine the status of the existing bridges in a transportation network based on the damage observed.
The temperature effect is one of the main causes of structural cracks and other damage in bridges. There are no temperature gradient patterns and recommended values for bridges in different regions. The temperature gradient model and its recommended value in China's General Specifications for Design of Highway Bridges and Culverts (which references the American Association of State Highway and Transportation Officials' LFRD Bridge Design Specifications) are not divided by geographic location. Based on field temperature test data and 50 years of meteorological data from the Qiqihar tied-arch bridge, a thermal conductivity model of the temperature field is established using the finite-element analysis method. The vertical temperature gradient model and its recommended value for a 100-year service life in alpine regions are determined. The model parameters are rigorously grounded in the statistical range of observed regional climate data, ensuring the fundamental validity and local representativeness of the model. The rationality of the findings is verified by comparing with the specifications of China, the United States and Japan, providing a technical support for engineering applications in alpine regions.
This study proposes a novel framework for optimising bridge construction investments by integrating time-dependent reliability (TDR) with financial profitability metrics. Using stochastic modelling of resistance degradation and traffic load dynamics, a dual-objective optimisation model is developed that (1) maximises transportation profit under fixed budgets and (2) minimises initial costs while preserving profit targets. A case study of 20 bridges demonstrates a 2.97% profit increase and 5.054% cost reduction by using mixed-integer linear programming. Key innovations include the 'investment factor' (k(in)) linking initial resistance design to life-cycle profitability and Pareto-optimised resource allocation. The framework bridges gaps between theoretical TDR advancements and practical engineering economics, offering actionable insights for infrastructure planners.
Bridges and viaducts are primary assets on transport infrastructure systems. The recent failures of the Francis Scott Key Bridge and the Polcevera Viaduct have highlighted the need to regularly reconsider the resilience of bridges. The disruption to railways and seaways below these bridges has highlighted the need to consider all uses of the bridge, not just those on the structure. This paper outlines a new method to estimate the resilience, using data on the use of the bridge based on the number of road lanes, rail lines, footways or navigable waterways on or under the bridge as the measure of performance or functionality. The data for ten bridge collapses, with use functionality data and dates from which the restoration times are derived, are used to determine resilience. The results of the study show a correlation of increased resilience index with increasing restoration time. There is less correlation of resilience with bridge size based on number of lanes or lines. The consideration of all uses of the bridge (both over and under) can affect the calculated resilience index.
