This experimental and numerical paper presents a modified version of the conventional steel plate-rubber pad device to replicate tyre-load contact pressure distributions (CPDs) on fibre reinforced polymer (FRP) bridge decks, as required by CEN/TS 19101. The steel plate remains, but underneath, the single continuous rubber-only pad of the conventional approach is replaced by strips that in plan match the tyre tread contact patches, each strip comprising stacked cork and rubber layers. The plate is indeterminate owing to these multiple strip supports underneath. Hence, the load applied to the plate is distributed between and along strips according to the strips’ stiffness profiles, which in turn are manipulated by tuning the thicknesses and stacking sequences of the cork/rubber layers. It is shown experimentally that both n and M CPDs from lorry and van tyres are successfully replicated via this approach. Test-verified finite element analysis reveals that suitably designed bi-material strips correctly mimic local tyre load effects across the deck, but that the conventional continuous mono-material pad either significantly over-emphasises or conversely runs the risk of significantly under-emphasising these local effects in some parts of the deck, and so could either trigger damage sites within the deck that are non-existent under tyre loading or can conceal damage sites that are induced by this tyre loading. Bi-material strips beneficially retain the simplicity of conventional plate-pad systems, while closely mimicking tyre CPDs. • Tests on application of narrow van tyre concentrated loads to cellular FRP decks. • Sensors used to log action (contact pressures) and deck’s local response (strains). • Devised bi-material cork-rubber strips under steel plate to mimic tyre tread loads. • Both n-shaped and M-shaped contact pressure distributions are reproduced by strips. • Mono-material pads can strongly exceed tyre effects to cause spurious damage sites

Steel Thin-walled Beams with restrained flanges are commonly used in structural systems where partial or full lateral and rotational restraints may occur, such as in steel–concrete composite beams used in slabs and in highway bridge decks. While these restraints enhance global stability, they can also trigger complex buckling behaviours. One such mode is lateral-distortional buckling (LDB), which arises when the tension flange is restrained against both lateral translation and rotation, leading to web distortion and twisting of the compression flange during buckling. Numerous studies have shown that existing empirical methods for predicting the elastic critical moment of LDB lack sufficient accuracy. This paper presents a numerical approach for estimating the elastic lateral and distortional buckling capacity of thin-walled I-beams under uniformly distributed loading. The developed method, referred to as Distortional Beam Formulations (DBF13), offers an efficient and practical modeling framework that incorporates second-order shell kinematics to accurately capture LDB behaviour. To validate the proposed formulation, Shell-element models were used in case studies and compared against existing experimental and analytical data. A total of 3540 analyses were conducted on doubly-symmetric and mono-symmetric I-section models under various boundary conditions to evaluate DBF13 across different buckling scenarios. Additionally, the effects of the cross-section classification, beam span, flange and web slenderness ratios were examined. The case study results underscore the reliability of DBF13 in predicting the Lateral Torsional Buckling as well as the Lateral Distortional Buckling behaviour. In the eigenvalue predictions, DBF13 has shown an average difference of less than 11% compared to shell model results.

Experimental and numerical studies on Longitudinal flexural performance of thin UHPC bridge deck with cavities

Path-dependent M-integral analysis of double fatigue crack interactions in orthotropic steel bridge decks

Bending-tensile behavior of composite twin I-girders using UHPC-NC hybrid bridge decks: Experimental and numerical analysis

Identification of the aerodynamic coefficients and forces of vortex-induced vibration of bridge decks based on the particle filter algorithm

Integrated ultrasonic testing and numerical simulation for damage detection in steel bridge deck pavements

Fatigue cracking and stiffness degradation remain critical challenges for concrete flexural members used in bridge decks, crane beams, pavements, and other structures subjected to repeated loading. Layered beams that combine normal concrete in the compression zone with steel-fiber concrete in the tension zone offer a promising route to reduce self-weight while retaining crack resistance and ductility. However, the coupled influence of layer depth and fiber dosage on the flexural fatigue response of such members is still insufficiently quantified for reliable engineering design. Unlike previous studies that mainly focused on homogeneous SFRC members, UHPC-based members, or layered beams under static loading, the present study addresses a more practice-oriented but less explored problem, namely the flexural-fatigue behavior of cast-in-place layered beams composed of normal concrete in compression and steel-fiber concrete in tension. More importantly, the study does not examine fiber effect or layer geometry separately, but quantifies within one unified framework how lower-layer height ratio and fiber dosage jointly govern fatigue life, stiffness retention, crack development, and failure transition. A calibrated nonlinear finite-element model with damage-plasticity constitutive laws and cycle-block degradation was further established to reproduce the experiments and to conduct a broader parametric study. The results show that no horizontal crack formed at the cast interface and that the strain-deflection response preserved the typical three-stage fatigue evolution. Increasing either the steel-fiber volume fraction from 0.8% to 1.6% or the lower-layer height ratio from 0.5 to 0.7 markedly prolonged fatigue life and improved crack control. A practical fatigue-life relation, a stiffness-degradation law, and a numerical response surface are proposed, indicating that a height ratio of 0.6–0.7 combined with a fiber dosage of 1.2%–1.6% provides the best balance between fatigue durability, stiffness retention, and failure ductility.

To investigate the fatigue performance of a novel green low-carbon steel–AAUHPC (Alkali Activated Ultra-high Performance Concrete, AAUHPC) composite bridge deck and achieve its structural optimization, this paper proposes a steel–AAUHPC composite bridge deck structure featuring double-sided welding of U-shaped ribs. Firstly, the numerical model of a symmetrical composite bridge deck is established by ABAQUS finite element software. The stress response of key fatigue structural details is analyzed, and the fatigue life is evaluated based on the S-N curve method. At the same time, the calculation results are compared with the orthotropic steel bridge deck and the steel–UHPC composite bridge deck. Secondly, the CCD method and RSM method are used to construct a mathematical regression model with the structural weight W per unit area and the fatigue stress amplitude of key details as the target. Finally, NSGA-III is used to optimize structural parameters such as AAUHPC thickness, top plate thickness, diaphragm thickness and spacing to obtain the Pareto-optimal solution set. The results show that the AAUHPC material has both environmental protection and excellent mechanical properties, and its compressive and splitting tensile strength is significantly higher than that of ordinary concrete, which is close to the UHPC level. The steel–AAUHPC composite bridge deck can significantly improve the fatigue performance of the orthotropic steel bridge deck. After laying the AAUHPC layer, the stress amplitude of each fatigue detail decreases, and the C1 detail decreases by up to 69.4%. Except for the C6 detail, the rest of the structural details meet the infinite-life design criteria, and the overall improvement effect is comparable to that of the steel–UHPC composite bridge deck. The constructed response surface model has good prediction accuracy. The optimization results show that the fatigue stress amplitude and the structural weight W are mutually restricted. Among the 15 sets of Pareto-optimal solutions obtained, solution U8 achieves weight minimization under the premise of satisfying the infinite-fatigue-life criterion. The optimal parameter combination is: AAUHPC thickness of 40 mm, top plate thickness of 10 mm, diaphragm thickness of 16 mm, and diaphragm spacing of 2400 mm. The research results can provide a theoretical basis for the fatigue design and engineering application of a new green steel–AAUHPC composite bridge deck.

Bridges are essential for national and regional connectivity, yet their deck slabs often deteriorate over time due to excessive loads, material fatigue, and environmental exposure, potentially reducing their structural safety. This study evaluates (1) the structural performance improvement of the Pute Bridge-river deck slab after strengthening with Glass Fiber Reinforced Polymer (GFRP) and (2) the cost efficiency of GFRP compared to conventional slab replacement. The methodology involved structural modeling using the SAP2000 v22, static load testing using a Deflection Multimeter (DMM), and cost analysis based on Analisa Harga Satuan Pekerjaan (AHSP) translated as Unit Price Analysis. The results indicate a 20.80% increase in load capacity (from 274 to 331 tons) and over 90% reduction in deflection at critical points, with mid-span deflection decreasing from -66.70 mm to -3.50 mm. Economically, GFRP strengthening costs 518,792,152.60 Rp, making it 28.62% more economical than slab replacement. Overall, GFRP proves both technically effective and cost-efficient, making it a significant solution for bridge deck slab rehabilitation due to its time efficiency, minimal traffic disruption, and long-term durability.

In this study, the use of simple attachments to existing guardrail members was investigated to evaluate their potential for reducing the overall drag force on long-span bridge decks. Wind tunnel testing and computational fluid dynamics (CFD) analysis were conducted to reveal the drag force reduction effect with the placement of attachments onto the rear sides of guardrails. A series of case studies of single-rail members and three-layer guardrails was performed to determine the optimal shape. A steel twin-box suspension bridge with a main span of 1545 m was selected as a prototype bridge deck, and the evaluation indicated an overall drag reduction ratio of 11.1% when an optimal attachment was applied. CFD analysis was also conducted to clarify the mechanisms responsible for the drag reduction achieved by the modified guardrails and to address Reynolds number effects. This study demonstrates the importance of optimizing the aerodynamic shape of guardrails and achieving drag force reduction by adding attachments to the rear sides of the guardrails without compromising the crash performance.

Experimental study on the interfacial shear performance of a novel steel-NC-UHPC composite bridge deck system

Large-scale testing of precast bridge deck girder repaired with shape memory alloy coupled prestressing plates

Parametric effects induced by atmospheric turbulence have emerged as an important factor influencing the aeroelastic behavior and extreme response of long-span suspension bridges. Originating from angle-of-attack fluctuations due to large-scale turbulence, these effects can significantly modify aerodynamic damping and stiffness, particularly for streamlined bridge decks. Long-term analysis, mainly adopted in the field of offshore structures, overcomes some limitations of classical Davenport theory-based approaches for calculating the dynamic response to turbulent wind of flexible structures, such as long-span suspension bridges. Among other aspects, it accounts for the influence of the statistical variability in turbulence parameters on the structural response, which is expected to impact on the actual role played by parametric effects of turbulence. However, accounting for these effects typically requires time-domain simulations, leading to prohibitive computational costs. This study introduces an efficient frequency-domain framework that incorporates the most significant parametric effect of turbulence (the so called "average parametric effect'') into the long-term evaluation of extreme response. The proposed formulation also includes static response and flutter instability, two aspects usually overlooked in previous contributions. The methodology is applied to the Halsafjorden Bridge, a planned 2000-m span suspension bridge in Norway. Three different wind scenarios, in terms of turbulence intensity and mean wind speed, are also considered. Long-term extremes are close to the results of the classical short-term approach if the mean wind speed is the only environmental random variable. In contrast, non-negligibly larger long-term responses are obtained if the randomness in turbulence intensity is also considered. Moreover, results reveal that the parametric effects of turbulence can significantly increase the long-term extreme response, particularly in torsion, where turbulence-induced damping reductions may lead to response increments of up to 41% for a return period of 100 years. Their impact is greater than in classical short-term analyses, where the average parametric effect leads to an increase in the torsional response of about 33%. This behavior is even more pronounced for higher return periods. These findings highlight that the combined influence of parametric effects of turbulence and randomness in the environmental parameters (e.g., turbulence intensity) can properly be assessed only within a long-term analysis.

Acoustic black hole structures for vibration reduction of orthotropic steel bridge decks

A machine learning and multi-source authentic data-driven framework for accurate fatigue life prediction of welds in existing steel bridge decks

This study presents a combined experimental and numerical validation of a high-resolution distributed acoustic sensing (HR-DAS) system for continuous strain monitoring in a full-scale fibre-reinforced polymer (FRP)–concrete composite bridge deck. The deck specimen, representative of a typical road bridge configuration, comprised a glass-carbon FRP trapezoidal girder integrated with a cast-in-place concrete slab. A four-point quasi-static bending test was conducted to assess the performance of HR-DAS in capturing distributed strain profiles along the girder. Five ultra-low-loss enhanced back-reflecting (ULEB) optical fibres with embedded reflectors were bonded to the girder surface and interrogated using an HR-DAS system. Conventional sensors, including strain gauges and linear variable differential transformers (LVDTs), were used in parallel for validation. A 3D finite element model (FE) was developed in ABAQUS and validated against experimental strain and deflection data. Close correlation was observed between HR-DAS measurements, strain gauges, LVDTs, and FE predictions, with strain and deflection ratios showing mean errors within 10 %. Additionally, the HR-DAS system demonstrated capability for capturing spatiotemporal strain profiles with a 1 kHz sampling rate. These results confirm the accuracy, resolution, and scalability of HR-DAS for structural health monitoring of FRP–concrete composite bridge structures, supporting its application in long-term, real-time monitoring under service conditions.

Local load-bearing stability of UHPC hollow-core bridge deck structure: Experimental and theoretical research

Study on mix design and properties of basalt fiber-reinforced concrete for bridge deck pavements in dry-cold regions with large temperature differences

This study proposes a flexible aerodynamic strategy to mitigate vortex-induced vibrations (VIVs) in Π-shaped bridge decks. The concept is based on the deformation and flapping motion of flexible plates installed along the deck edges. To evaluate the effectiveness of this approach, wind tunnel tests were conducted on a Π-shaped section with an aspect ratio of 8.35. Three types of mitigation devices, i.e., flexible L-shaped deflectors, lower central stabilizing plate, and lower edge stabilizing plates, were installed with various lengths and stiffnesses to examine their aerodynamic performance. Numerical simulations were further carried out to clarify the flow–structure interaction mechanism associated with the flexible L-shaped deflectors. The experimental results show that the flexible L-shaped deflectors demonstrate superior mitigation performance for both vertical and torsional VIV of the Π-shaped section, with improved suppression effectiveness as their height or stiffness increases. The flow mechanisms indicate that VIV suppression is primarily achieved through a combination of upstream flow deflection caused by the plate deformation and downstream vortex modulation induced by the flapping motion. This mechanism modulates the vortices at the trailing edge of the girder, reducing their characteristic size and energy and altering the spatial orientation of vortex shedding in the wake.