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This study investigates the wind‐induced flutter phenomenon of long‐span suspension bridges. A mathematical model is established using the energy method, considering the nonlinear aeroelastic behavior of a bridge deck constrained by vertical suspenders under cubic nonlinear damping. The aerodynamic self‐excited force is obtained using the Scanlan flutter theory. The critical state of flutter and the relationship between the amplitude and parameters of the limit cycle oscillation (LCO) are obtained by solving the nonlinear flutter equation using the average perturbation method. The Hopf bifurcation is confirmed to occur in the critical state of the nonlinear motion model using the Jacobian matrix. The results are verified using the Runge–Kutta numerical method, and it is found that the nonlinear response of the flutter LCO is in general agreement with the numerical solution. The study also shows that the degenerate Hopf bifurcation appears at the critical state under the condition of lower cubic damping coefficient, and the nonlinear flutter bifurcation changes from a degenerate Hopf bifurcation to a supercritical Hopf bifurcation as the cubic damping coefficient grows. [ABSTRACT FROM AUTHOR]

The design of suspension bridges predominantly emphasizes wind and earthquake loads, frequently overlooking the consideration of extreme events in the design stage, thus posing a threat to bridge safety. The purpose of this research is to spread awareness among engineers for identifying weak zones in a bridge and to provide a new insight into how much damaging the blast loading could be for the long-span suspension bridges if not designed properly under the blast loads. The current dynamic analysis procedures for bridges under blast loads are complex and computationally expensive, making them unsuitable, especially for long-span bridges. To address this, a simplified dynamic analysis approach is proposed to assess the structural response and extreme limit state of suspension bridges exposed to blast loads. The method involves a bilayer solution: blast loading is modeled as nodal loads, and the structural aspect is represented by a three-dimensional (3D) fishbone skeleton finite-element (FE) model. Time-history simulations of blast loads are conducted for various bridge locations and explosive sizes. The parametric dynamic analysis reveals that the tower top node is the most vulnerable location in the suspension bridge under blast loads, which potentially exceeds the stress limits of nearby main cable elements and triggers the zipper-type progressive failure of the entire suspension bridge. Similarly, blasting at the deck nodes nearby tower on the main span side as well as on the side span side significantly amplifies axial stresses in nearby suspenders and the main cable, i.e., demand-to-capacity ratios of C18 and C19 surpass unity under BS4-6W and BS4-8W, respectively confirming that the failure state has reached for C18 and C19 under medium- to large-sized explosives. Therefore, it is recommended that the maximum demand-to-capacity ratio for all bridge components under medium- to large-sized explosives shall be kept below 0.8 to ensure the safety of the entire structure under extreme limit state. Practical Applications: This paper provides a methodology to investigate the structural redundancy of suspension bridges under extreme limit state by providing a bilayer solution: the blast aspect, which is simulated as nodal loads on the bridge road surface and the structural aspect, is simulated as a 3D fishbone skeleton FE model. The implicit dynamic analysis approach is adopted parametrically by considering variable explosive weights and locations. For each blast scenario, the time-history of nodal loads is applied to various locations of the bridge considering small- to large-sized blasts. From a practical viewpoint, this study is relevant to develop comprehensive understanding of the dynamic behavior exhibited by long-span bridges when subjected to extreme loading scenarios. In essence, the aim is to explore the benefits and applicability of this research to the design of long-span bridges under blast loading conditions. The simplified approach presented in this paper, along with the corresponding bridge response results, allows a bridge design engineer to analyze a suspension bridge effortlessly. This method eliminates the need for intricate computations required to assess blast pressure over a solid bridge model, enabling a straightforward visualization of the anticipated behavior under blast loading. The research serves a crucial role in checking and verifying the extreme limit state, in addition to assessing the serviceability and ultimate limit states according to AASHTO's requirements. For existing suspension bridges, the study proves beneficial in formulating a comprehensive blast-resistant plan through retrofitting and strengthening identified weak zones. Consequently, this research holds practical significance, serving as a foundation for further exploration and investigation into the effects of blast loading on various types of long-span bridges. [ABSTRACT FROM AUTHOR]

In this paper we study the stability of pullback exponential attractors with respect to perturbations for non-autonomous extensible coupled suspension bridge equations. The governing equations describe the vibration of the roadbed in the vertical plane and that of the main cable. Under quite general assumptions on nonlinear damping and sources terms and based on nonlinear semigroups and the theory of monotone operators, we establish existence and uniqueness of weak and strong solutions. By applying a criterion developed for continuous and non-autonomous models by Yang and Li [34], we construct a family of pullback exponential attractors stable with respect to perturbations. [ABSTRACT FROM AUTHOR]

This study investigates the vulnerability of long-span suspension bridges to spatially variable vertical ground motions (SV-VGMs). While of recognized importance, a comprehensive understanding of this topic has been traditionally limited by the unavailability of an adequate number of arrays of motions. In this work, 10 simulations of a large-magnitude Hayward Fault earthquake are utilized to perform site-specific structural response assessments of a suspension bridge under different load scenarios. A detailed nonlinear model representative of the West San Francisco-Oakland Bay Bridge is employed as the case study structure. Four sets of nonlinear time-history analyses are performed with and without VGMs and with and without the incorporation of spatial variability to offer the basis for a complete comparison of the demand distributions across different load cases. Results indicate that VGMs largely influence the response of the bridge decks in the vertical direction, with an increase in drifts up to 2× for the case of synchronous input and up to 2.5× for the case of asynchronous inputs. The analysis of the bridge response in the time and frequency domain across all load cases reveals a high sensitivity of the decks' response to minor time lags in input motions of comparable amplitude, which are seen to activate the contribution of higher modes to the structural response. Evidence from this study points to the potential of severely underestimating structural demands if the (even limited) spatial variability of the input motions is not incorporated correctly. For the case study structure, the probability of exceeding the onset of nonlinearity in the short decks at the design earthquake level is seen to increase by a factor of about two when considering SV-VGMs as opposed to synchronous horizontal motions only. [ABSTRACT FROM AUTHOR]

This study introduces a new main cable protection system designed to mitigate the issue of cable corrosion by circulating dry air from within the main cable. The proposed protection system effectively addresses the limitations of traditional anticorrosion techniques. In this study, the primary focus was on the initial design of the key structure for the new main cable protection system. Moreover, a comprehensive dehumidification test was conducted on a full-scale model of the main cable to validate the radial strength of a new ventilation pipe and assess the impact of the proposed corrosion protection system. The dehumidification efficiency of the new main cable protection system was verified in comparison to the traditional main cable protection system. The results indicate that the newly designed ventilation pipe exhibited minimal radial deformation when subjected to cable clamp pressure. Therefore, the ventilation pipe meets the strength criteria for the internal utilization of the main cable. The ventilation pipe's opening hole scheme was configured at 6 × Ø4 to guarantee that the entire main cable is enveloped by the dry air supplied into it. Relative humidity at each measurement point along the main cable was observed to decrease to below 60%. Consequently, the proposed main cable dry air protection system can attain the anticipated anticorrosion outcome. Under the test conditions, the dry air utilization rate of the proposed system exceeded that of the traditional main cable anticorrosion system by approximately 15.4%. This suggests that the new system exhibits a higher dry air utilization rate and dehumidification efficiency than the traditional system. The study results validate the dehumidification effect of the new system and endorse its utilization in primary cable anticorrosion projects. [ABSTRACT FROM AUTHOR]

Generalized structural and aerodynamic torsional stiffness of a suspension bridge with a main span length of 3000m are discussed first qualitatively in terms of analytical models. Two torsional divergence (TD) modes, symmetric and asymmetric, are compared in terms of the evolution of generalized torsional stiffness properties. It demonstrates that symmetric TD occurs prior to the asymmetric TD in a vast range of main span lengths. Numerical simulations of TD are then performed by the static finite element (FE) method. The results turn out a much lower critical wind speed of TD presented by the analytical model, due to stiffness degradation caused by main cable deformations. Finally, the effects of two types of countermeasures are examined. The replacement of the original deck section by a central slotted one can boost the critical wind speed of TD by 30%. Widening the main cable spacing enhances almost linearly the system’s critical wind speed. A combined countermeasure of a slotted bridge deck and widened main cable spacing stabilizes substantially the system’s aerodynamic static stability, resulting in a 45% increase in the critical wind speed of TD. [ABSTRACT FROM AUTHOR]

As the combination of springs and vertical stabilizers, the movable downward vertical central stabilizer (MDVCS) is proposed to further control the nonlinear flutter of super long‐span suspension bridges in this paper. A series of flutter suppression tests of closed‐box girders and twin‐box steel girders with various MDVCSs are conducted. Based on the coupled flutter theoretical method, the sensitivity analysis of two important parameters including the height and stiffness of MDVCS are carried out to compare their nonlinear flutter control mechanism. The results show that the flutter critical wind speed (Ucr) of the closed‐box girder continued to increase with the decrease of the height of the DVCS and the increase of spring stiffness, whereas the Ucr of the twin‐box girder increased at first and then decreased. The cubic polynomial function and quadratic Holliday function are suitable to modify the correction coefficients of Ucr for the closed‐box girder with various stiffnesses and heights of MDVCS, while the Lorentz peak‐value function and cubic polynomial function are suitable to modify the Ucr of the twin‐box girder. Furthermore, the MDVCS significantly changes the rules of two positive and negative aerodynamic damping ratios for the closed‐box girder and two negative aerodynamic damping ratios for the twin‐box girder. Besides, the peak vertical displacement amplitudes of the box girder are about half of the MDVCS, since both the height and stiffness of MDVCS alter the elliptical radius of vertical phase planes to affect the limit cycle oscillation of soft flutter, especially for the leeward MDVCS for the twin‐box girder. [ABSTRACT FROM AUTHOR]

This study investigates the blast-resistant performance of a polyurea-coated suspension bridge girder under explosive loads. The Hunan Road Bridge of Shandong was used as a case study through combined test and numerical simulation methods. Two 3 kg TNT charges and one 5 kg TNT charge were used to conduct two single-blast tests and one repeated blast test on a 1:3 scaled segment of a box girder. The tests were labeled as G (box girder without polyurea), PCG (first blast on box girder coated with polyurea), and PCGR (second blast on box girder coated with polyurea). A 1.5 mm polyurea layer was uniformly applied to the top surface. Numerical simulations of the explosion response were performed and validated using LS-DYNA software. The results indicate that under 3 kg of TNT detonation directly above the top plate, sample G exhibited an elliptical perforation, whereas sample PCG only experienced minor local dents without penetration. After a second detonation of 5 kg of TNT above the box chambers, sample PCGR displayed a nearly circular perforation in the top plate, along with cracks near the supports of chambers 1 and 3. For the main girder of the suspension bridge, multiple detonation points caused severe damage, rendering it impassable. However, after polyurea coating, the blast resistance significantly improved, with only minor spalling of concrete on the top plate and no other notable damage, allowing for continued passage. The polyurea layer effectively reduced the vertical displacement of the girder, and this reduction plateaued with increasing coating thickness. Under a 500 kg TNT blast, the optimal polyurea thickness to enhance blast resistance was determined to be 9 mm. [ABSTRACT FROM AUTHOR]

Authentic assessment is often narrowly framed as tasks that mirror workplace tasks, resulting in on overemphasis on generic workplace skills at the expense of disciplinary knowledge. We place disciplinary knowledge at the heart of authentic assessment and explore how authentic assessment across a programme can contribute to an authentic view of the broad discipline of science. Through the metaphor of a suspension bridge, we explore relations between disciplinary knowledge, the nature of the discipline, feedback from assessment, and evaluative judgment. We argue that assessment of student reflection on the nature of science is an essential but often overlooked element of authentic assessment and provide data to support this claim. Critical reflection on the nature of science invites students to examine and question their worldview assumptions about what science is and how it works, giving them the epistemic agency to deeply engage with the often-controversial ways science interacts with society. [ABSTRACT FROM AUTHOR]

As the service age of bridges increases, the degeneration of the bridge components leads to changes in the importance of corresponding state assessment indices. Employing fixed weights in bridge service condition assessments may result in inconsistent outcomes with the actual conditions. Therefore, this paper proposes an index weight updating method that aims to achieve index weight updating based on the operational status of bridges, thereby enhancing the accuracy of bridge service condition assessment results. This method utilizes the bidirectional projection of fuzzy numbers representing index state intervals and ideal targets as the technique for order preference by similarity to an ideal solution (TOPSIS) evaluation criteria for index importance. This paper conducts case analyses of a suspension bridge across multiple service periods which comprise three primary conditions: periods of intact bridge status, suboptimal conditions resembling expected degradation, and damaged status due to external effects. The case study results demonstrate that the updated weight using the proposed method effectively reflects the influence of actual changes in bridge status on the importance of indices. In the cases of good condition or matching the expected degradative state, the updated weights obtained could better reflect the actual service condition of the bridge compared to fixed weights provided by standards. When considering the effect of accidents or other incidental factors, the updated weights obtained through the proposed method could reflect the influence of actual component conditions on the importance of indices while the initial weights and age-dependent updated weights cannot. Thereby, the assessment results derived from this approach are more consistent with expected states and maintenance levels, validating its effectiveness and comparative advantages over alternative methodologies. The results indicate that the proposed method can significantly enhance the rationality of assessment index weights, serving as a more effective and rational approach for evaluating bridge service conditions. [ABSTRACT FROM AUTHOR]

In the era of sleek, super slender suspension bridges, facing the issue of stability against dynamic wind actions represents an increasingly complex challenge. Despite the significant progress over the last decades, the impact of atmospheric turbulence on bridge stability remains partially not understood, evoking the need for innovative research approaches. This study aims to address a gap in current research by investigating the random flutter stability associated with variations in the angle of attack due to turbulence, which has not formally been addressed yet. The present investigation employs the 2D rational function approximation model to express self-excited forces in a turbulent flow. The application of this type of models to bridge dynamics yields a viscoelastic coupled dynamic system characterized by memory effects and driven by broad-band long-time-scale noise, described here by a linear homogeneous time-variant differential equation, which shows apparent nonlinear features, and which has rarely been matter of research. Utilizing a Monte Carlo methodology, this work innovates in applying the largest Lyapunov exponent (LE) and the moment Lyapunov exponents (MLE) to study bridge random flutter stability. The calculation of LE and MLE under diverse turbulent wind conditions uncovers lower flutter stability than without turbulence effects. In most cases, sample and low-order p-th moment stability thresholds closely align with the bridge dynamic response pattern; therefore, the flutter critical wind speed is unequivocal. However, under certain turbulence scenarios, it is necessary to resort to MLE for a complete description of stability, evoking some additional consideration of which statistical moments should be considered for the engineering assessment of the flutter limit. Finally, this work provides a qualitative insight into the instability mechanisms by approximating the random parametric excitation with a sinusoidal gust and evaluating the time-periodic system stability via Floquet theory. [ABSTRACT FROM AUTHOR]

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This study aims to address the complexities in the calculation of the tangent stiffness matrix and the issues of divergence in iterative calculations in the shape-finding process of existing suspension bridge main cables. The research investigates the factors influencing the computational errors of existing cable element theories and the convergence or divergence of the main cable shape-finding calculations. First, a nonlinear equation for calculating the height of the cable element is constructed. Subsequently, a formula for cable height calculation is established according to the differential equations of the deformed cable element. Finally, considering the mass conservation principle before and after the cable deformation, a nonlinear system of equations for the configuration of the cable element is derived. Given the symmetric nature of the mid-span structure and loading in most suspension bridges, it is inferred that the point of the lowest slope of the main cable in the completed bridge state serves as the symmetry center of the structure. Consequently, a symmetric main cable shape-finding method is developed. A comparative analysis between the proposed method and existing iterative methods was conducted in terms of calculation accuracy and convergence behavior. The results indicate that the difference in horizontal cable force at the IP point between the two methods is 1.9 kN, and the difference in unstressed length is 2.5 mm. The calculation efficiency of the symmetric main cable shape-finding method is more than twice that of traditional iterative algorithms, with the number of iterations required for convergence generally being lower than that of traditional methods. For initial values that cause divergence in traditional iterative methods, the symmetric main cable shape-finding method achieved convergence within 10 iterations. The derived cable element theory and the symmetric main cable shape-finding calculation method can lay a theoretical foundation for the refined and efficient calculation of the main cable shape-finding process. [ABSTRACT FROM AUTHOR]

To investigate the nonlinear flutter characteristics of long-span suspension bridges under different deck ancillary structures and configurations, including those with and without a central wind-permeable zone, as well as to analyze the hysteresis phenomenon of a subcritical flutter and elucidate the mechanisms leading to the occurrence of nonlinear flutter, this paper studies first the post-flutter characteristics of the torsion single-degree-of-freedom (SDOF) test systems and vertical bending–torsion two-degree-of-freedom (2DOF) test systems under different aerodynamic shape conditions are further analyzed, and the role of the vertical vibration in coupled nonlinear flutter is discussed. The results indicate that better flutter performance is achieved in the absence of bridge deck auxiliary structures with a central wind-permeable zone. The participation of vertical vibrations in the post-flutter vibration increases with the increase in wind speed, reducing the flutter performance of the main girder. Furthermore, the hysteresis phenomenon in the subcritical flutter state is observed in the wind tunnel experiment, and its evolution law and mechanism are discussed from the perspective of amplitude-dependent damping. Finally, the vibration-generating mechanism of the limit oscillation ring is elaborated in terms of the evolution law of the post-flutter vibration damping. [ABSTRACT FROM AUTHOR]

Suspension bridge hangers over 100m are prone to wind-induced vibration. To investigate the vibration characteristics of a suspension bridge hanger over 140m with two cables on a day affected by typhoon Sura, the field measurement of the wind field and acceleration of two cables at different heights was performed. The wavelet transform method was introduced to analyze the time–frequency characteristics of the hanger and girder, while based on the stochastic subspace identification method, the damping ratios of the hanger were identified. The cluster analysis was performed to investigate the relationship between the wind field and hanger vibration. The result of measurement at the site indicated that under the nonstationary wind, the hanger exhibited three different forms of vibration: vortex-induced vibration, buffeting, and another high-frequency vibration. The first two forms may be caused by the incoming wind, and the last one may be due to the vibration of the bridge deck. The vibration was the same between two cables, but different in multiple heights of a cable. For the same cable, there existed a linear relationship between the in-plane and out-of-plane vibration. The hanger exhibited single-mode and multimode vibrations with an elliptical or eight-shaped motion trajectory. For the multimode vibration, a clear energy alternation phenomenon between the dominant frequency and subdominant frequency was found. The out-of-plane acceleration was greater than the in-plane vibration due to the damping difference in the two directions. The wind field was divided into five clusters, and the clusters of the wind field were related to the mode of hanger vibration. [ABSTRACT FROM AUTHOR]

Precise finite element modeling is critically important for the construction and maintenance of long-span suspension bridges. During the process of modeling, shape-finding and model calibration directly impact the accuracy and reliability. Scholars have provided numerous alternative proposals for the shape-finding of main cables in suspension bridges from both theoretical and finite element analysis perspectives. However, it is difficult to apply these solutions to suspension bridges with special components. Seeking a viable solution for such suspension bridges holds practical significance. The Nanjing Qixiashan Yangtze River Bridge is the first three-span suspension bridge in China. To maintain the configuration of the main cable, the suspension bridge is equipped with specialized suspenders near the anchors, referred to as displacement-limiting suspenders. It is the first suspension bridge in China to use displacement-limiting suspenders and their anchorage system. Taking the suspension bridge as a research background, this paper introduces a refined finite element modeling approach considering the effect of geometric nonlinearity. Firstly, based on the loop adjustment and temperature correction, the shape-finding and force assessment of the main cables are carried out. On this basis, a nonlinear finite element model of the bridge was established and calibrated, taking into account factors such as pylon settlement and cable saddle precession. Finally, the static and dynamic characteristics of the suspension bridge were thoroughly investigated. This study aims to provide a reference for the design, construction and operation of the three-span continuous suspension bridge. [ABSTRACT FROM AUTHOR]

Suspension bridges, such as stress-ribbon, are among the simplest structural bridge systems and have the lowest structural height. The flexibility of these elegant bridges poses great challenges for designers to minimize their deformability under asymmetrical operational loads. Due to the small initial sag, such load-bearing structures also cause significant tensile forces, which requires them to have large cross-sections and massive anchor foundations. This paper analyzes an innovative suspension steel bridge structure combined with a string and a cable. More attention is paid to asymmetric loading as this is more relevant for suspension structures. The new structure is studied numerically and experimentally. It is established that the string stabilizes the displacements of the bridge under asymmetric loading. The stabilization efficiency is proportional to the value of the pre-tension force of the string. The obtained results reveal the behavior of the structure and enable an evaluation of the accuracy of the numerical results, as well as the applied modeling. In addition, the experimentally obtained results allow the evaluation of more aspects of the behavior of the new bridge, which will be useful in further studies of this type of structures. [ABSTRACT FROM AUTHOR]

Suspension bridges are the most common type of bridge used to cross the ocean. The cable clamps in suspension bridges clamp the main cables by bolt preload, but the elastic interaction of the bolts reduces the preload, which is detrimental to the force in suspension bridges. However, research on the factors influencing the elastic interaction of cable clamp bolts in suspension bridges is currently limited. This paper aims to explore the law of influence of external factors on the elastic interaction of bolts through a combined approach of theoretical analysis, full-scale experiment, and finite element simulation. The results indicate that the average preload loss was reduced by about 27% when the elastic modulus was increased by about 110%. The average preload loss was reduced by about 45% when the bolt center distance was increased by 75%. The number of bolts has a small effect on the elastic interaction, which can be ignored. When the preload of bolt installation was increased by 133%, the average preload loss was reduced by approximately 125%, which was almost a linear relationship. Tightening the bolt from the center bolt creates greater elastic interaction. The conclusions can provide suggestions for reducing the elastic interaction of bolts in the design and construction of suspension bridge cable clamps. [ABSTRACT FROM AUTHOR]

In this paper, a nonlinear and nonlocal model for suspension bridge-type structures with piers is studied. The model encompasses a coupled dynamics involving longitudinal u(x, t) and torsional θ (x , t) oscillations. Focusing the dynamics on a single specific Fourier component for both the variables, a coupled system of ODEs is obtained. For this latter system, we prove the occurrence of rich and complex dynamics—including infinitely many periodic solutions (harmonic and subharmonic)—for the longitudinal time component, when the torsional one is small. This goal is achieved by applying a rigorous analytical approach, based on the theory of linked twist maps. With respect to previous works on suspension bridge models, one of the main contributions concerns the fact that the nonlinear function f appearing in the original model is transformed, via finite-dimensional projection, into a new effective nonlinearity Γ f , λ whose dynamical effects may strikingly differ from those of f. This also depends on the magnitude of the coefficients related to the nonlocal terms. [ABSTRACT FROM AUTHOR]

The seismic performance of a long-span triple-tower suspension bridge is a critical consideration in engineering communities. To promote a better seismic design, this paper presents a parametric study on the structural seismic control using hysteretic steel dampers. The finite element model is firstly established, and an introduction to the mechanical properties of the E-shaped hysteretic steel damper is made. Then, a seismic analysis is conducted under uniform earthquake excitations. Considering the effect of wave passage, the performance of hysteretic steel dampers in seismic control is further analyzed. The results indicate that the travelling wave effect greatly affects seismic responses. Increasing the damper elastic stiffness can effectively reduce the relative displacement between the main girder and either the left or the central tower. This treatment is effective for the right tower only when the wave velocity is among 400–1600 m/s, while it makes little contribution in other ranges. At an arbitrary wave velocity, increasing the damper elastic stiffness would cause minor changes to the shear forces of side towers, while its influence on the central tower is significant. A reasonable damper design for the long-span triple-tower suspension bridge depends on an essential prior evaluation of the wave velocity based on soil conditions. [ABSTRACT FROM AUTHOR]

In the present paper, we examine a suspension bridges model subject to frictional damping, a fractional delay term, and a source term. First, we prove the existence of global solutions of the problem. Second, for small initial data, we establish the exponential stability of the system by using the energy method. Additionally, we show that if the initial energy assumes a negative value, the solution blows up in finite time.

The existence of water-filled barriers alters the cross-sectional shape of the main girder, which may lead to vortex-induced vibrations (VIVs) in suspension bridges. However, the mechanism and occurrence conditions of VIVs in the main girder that is affected by water-filled barriers are still unclear. To this end, this study investigates the effect of water-filled barriers on the VIV performance of suspension bridges. The evolution of the vortex structure during one VIV cycle and the corresponding pressure variations, including the average and fluctuating values on the surface, were analyzed. Additionally, the spatiotemporal distribution of the surface pressure was studied using proper orthogonal decomposition (POD). The results show that VIV occurs in the main girder when the height of the water-filled barriers exceeds a threshold value of 0.317. Moreover, a significant negative pressure vortex occurred when the barriers were installed. The vortex underwent the following distinct phases in one VIV cycle: generation, separation, reattachment, and shedding. However, the negative pressure vortex behind the barrier did not vary substantially when the water-filled barriers were installed without VIV. Additionally, the average pressure on the surface of the main girder remained constant regardless of the occurrence of VIVs. In the presence of VIVs, the pressure fluctuations became much more pronounced and were mainly concentrated on the top surface and leading edge of the main girder. Additionally, the dominant modes of the pressure variations correlated with the evolution of the vortices and pressure distribution. [ABSTRACT FROM AUTHOR]

To study the influence of the Chinese high-speed railway ballastless track spectrum and the German low-interference spectrum on riding comfort, a long-span highway-railway suspension bridge is studied as an example, and a passenger–train–bridge coupling model is established based on the structural dynamics. The vibration responses of the passenger–train–bridge system during the CRH2C train running on the bridge are studied by a combination of the self-written computer program and general finite element software, considering the hunting movement, and the riding comfort of trains and passengers is evaluated using NMV and ISO-2631 standard, respectively. The results show that track irregularity has a few effects on the lateral vibration of the bridge. Compared with the German low-interference spectrum, the Chinese high-speed railway ballastless track spectrum has less exciting effects on the vibration of the passenger–train–bridge system and better riding comfort. Passengers in the middle of the train and on the middle seats of the same train have better riding comfort, and with the increase of train speed, the riding comfort of passengers will gradually reduce. Instead of passenger responses, the riding comfort classification based on the car body is overestimated. [ABSTRACT FROM AUTHOR]

This study addresses the limitations of existing indirect bridge damage identification methods that are based on the vehicle–bridge coupled vibration theory of highway bridges. To overcome these shortcomings, we propose an extended approach that incorporates various types of deep-learning models with vehicle–bridge coupled vibration responses. The proposed method is demonstrated using a three-span continuous beam bridge as a case study. First, a vehicle and bridge analysis model is established, and bridge damage is simulated using unit stiffness reduction, considering different damage scenarios. Next, to account for road roughness randomness, vehicle–bridge coupling vibration analysis is performed under various road roughness conditions, yielding the vertical acceleration vibration signal of the vehicle. Subsequently, we employ an end-to-end damage recognition method, utilizing the vehicle acceleration response as the network input, to construct two types of deep-learning models: one-dimensional convolutional neural network (1D-CNN) and convolutional long short-term memory neural network (CNN-LSTM). The recognition performance of both models is compared and analyzed. Taking Zhengzhou Taohuayu Self-Anchored Suspension Bridge in China as an example, this study delves into the capability of bridge damage identification using deep learning. The results demonstrate that the one-dimensional convolutional neural network achieves excellent recognition performance in terms of both damage location and severity. [ABSTRACT FROM AUTHOR]

The development of a bridge damage detection method relies on comprehensive dynamic responses pertaining to damage. The numerical model of a bridge can conveniently considers various damage scenarios and acquire pertinent data, while the entity of a bridge or its physical model proves challenging. Traditional methods for identifying bridge damage often struggle to effectively utilize data acquired from diverse domains, presenting a significant hurdle in addressing cross-domain issues. This study proposes a novel cross-domain damage identification method for suspension bridges using recurrence plots and convolutional neural networks. By employing parameter identification-based modal modification of numerical model, the gap between numerical model and physical models eliminated. Un-threshold multivariate recurrence plots are used for accurately characterizing dynamic responses and extracting deeper damage features. Due to the scarcity of experimental data, which limits the training of robust neural networks, a transfer learning tailored for convolutional neural networks is implemented. This strategy not only addresses the issue of small sample sizes but also significantly enhances the network's ability to identify structural damage across diverse bridge domains. The proposed damage identification method is validated using a combination of numerical simulations and physical experiments on a specific single-span suspension bridge. Results demonstrate that un-threshold multivariate recurrence plots reveal detailed internal structure and damage information. Furthermore, the utilization of improved convolutional neural networks effectively facilitates cross-domain structural damage identification, marking a significant advancement in the field of structural health monitoring. [ABSTRACT FROM AUTHOR]

This study employs advanced techniques, namely the improved multi-synchrosqueezing transform (IMSST) and the Fouriersynchrosqueezed transform (FSST), to extract the instantaneous frequency of the Humber Bridge, in the UK, in operational conditions. First, a brief overview of the relevant theories behind the techniques used is provided. These techniques are then applied to track the instantaneous frequencies within the monitored vertical acceleration data of the bridge. The instantaneous frequencies extracted by both techniques are verified against each other. The investigation further encompasses the development of three distinct regression models: a simple regression model, an expanded regression model and a regression model based on principal component analysis (PCA). The efficacy of the PCA-based model is scrutinised by generating and testing datasets that mirror the monitored data, with the Kolmogorov-Smirnov (KS) test confirming theirvalidity. The findings of this research indicate a statistically significant inverse relationship between modal frequency and acceleration intensity. Furthermore, by incorporating wind effect considerations into the regression analysis, the R-squared values in both the expanded and PCA-based models exhibit substantial improvements. This demonstratesthe performance of the enhanced model in capturing the dynamics of the bridge. The robustness of the PCA-based model is furthercorroborated by its performance during testing, proving its potential as a reliable tool in structural health monitoring (SHM). [ABSTRACT FROM AUTHOR]

The development tendency of lightweight and higher-speed regarding trains goes against the safety and comfort requirement of high-speed trains, especially in the scenario of the train running on bridges within crosswind environments. Wind barriers have been proven to be an effective measure to guarantee the train's operation security. In this paper, a new type of wind barrier consisting of the fence-type wind barrier form and open hole-type wind barrier form has been proposed. Then, a series of wind tunnel tests about the large-scale section model of a large-span suspension bridge installed with different wind barriers have been conducted. The effects of three different forms of wind barrier including fence-type, open hole-type, and combined-type on the aerodynamic characteristics of the train-bridge system have been analyzed. The windproofing effectiveness and the protection mechanism of the combined-type wind barrier on the train-bridge system have been revealed through the measured aerodynamic characteristics. The results show that the installation of open hole-type, fence-type, and combined-type wind barriers at a height of 4 m and a ventilation rate of 19% yields a maximum reduction in the train drag coefficient of 67.70%, 72.92%, and 97.21%, respectively. Moreover, the combined-type wind barrier can improve the train-bridge system's aerodynamic performance and trains' running safety on bridges when comparing with the open hole-type and fence-type wind barriers. The proposed combined-type wind barrier can provide a more efficiency and practical way for the high-speed train's running safety on the bridge. [ABSTRACT FROM AUTHOR]

Bridges are fundamental facilities in the transportation system, and their operational performance is crucial for economic and social development. Many large bridges are now equipped with structural health monitoring (SHM) systems that collect various types of real-time data. However, our user study found that despite the accumulation of massive amounts of monitoring data, current analysis methods cannot efficiently process large-scale, high-dimensional data. To address this, we have developed BOPVis, a visualization system for bridge monitoring data. BOPVis allows users to intuitively locate sensors and extract corresponding data from a 3D digital model of a bridge. It also provides convenient and flexible interactions for examining trends over time and correlations across hundreds of monitoring channels. A real-world long-span suspension bridge in China is used as a case study to demonstrate the advantages of the BOPVis system for operational performance mining. Through BOPVis, the global temperature deformation behaviors of the bridge are explored and found to align with the physical mechanism documented in the SHM literature. The BOPVis system, with its interactive visualization analysis capabilities, offers a new method for analyzing bridge monitoring data. [ABSTRACT FROM AUTHOR]

In the present paper, we examine a suspension bridges model subject to frictional damping, a fractional delay term, and a source term. First, we prove the existence of global solutions of the problem. Second, for small initial data, we establish the exponential stability of the system by using the energy method. Additionally, we show that if the initial energy assumes a negative value, the solution blows up in finite time. [ABSTRACT FROM AUTHOR]

In this paper, we study the asymptotic behavior of solutions for unconstrained one dimensional suspension bridge model. We dissipate the system with two nonlinear dampings of variable exponents-type. We obtain exponential and polynomial decay results based on the range of the variable exponents by using the multiplier method. Our results built on, developed and generalized some earlier results in the literature. [ABSTRACT FROM AUTHOR]

The accuracy of main cable construction in suspension bridges is directly influenced by the sag of the strands during the erection process. Thus, effective methods for controlling strand sag are crucial. However, the current control standards and methods are primarily based on practical engineering experience, lacking quantitative analysis and a sufficient basis. This paper aims to address this gap by summarizing four commonly used strand sag control methods and proposing a quantitative analysis model that considers the influence of random factors. The model quantifies the impact of these methods on the main cable shape and strand tension after cable tightening. To illustrate the practical application, a suspension bridge is utilized as a case study. The results of the study illustrate a linear relationship between the main cable sag and inter-strand distance, with each control method exhibiting a varying linear change rate. Moreover, the discrepancy in strand distance contributes to uneven strand tension after cable tightening. Random errors contribute to the dispersion of the main cable sag and strand tension, which are further exacerbated by cumulative errors between layers of general strands. Based on the study's results, this paper provides valuable references for the erection and control of the main cable in suspension bridges. [ABSTRACT FROM AUTHOR]

In a suspension bridge, slippage may occur at the saddle–cable interface during an earthquake. A refined finite element model of the saddle–cable interface is proposed which considers the compressive force and friction force at the curved contact surface. To investigate the saddle–cable slippage during an earthquake, the finite element model of a suspension bridge was built, and nonlinear time history analysis was conducted. Furthermore, the effects of the friction coefficient at the saddle–cable interface, the pounding between the suspension bridge and the approach bridges, the fluid viscous damper, and the rigid central buckle were evaluated by parametric analysis. The result shows that the saddle–cable slippage affects the overall seismic response of the suspension bridge slightly. The saddle–cable slippage is affected significantly by the friction coefficient of the saddle–cable interface, fluid viscous damper, and the rigid central buckle. [ABSTRACT FROM AUTHOR]

The present study is done in the Beas river (Manali to Mandi town) after the July 2023 flood to assess the geomorphic and geological vulnerability of the terrain and understand the role of human intervention in the disaster. The study is based on preliminary field observations and morphometric analysis that indicates that the surfaces proximal to the trunk riverbed and the ephemeral tributary channels suffered maximum damage. Along the upper Beas river, the lateral erosion caused by hyperconcentrated flows saturated with paraglacial sediments partly obstructed the river and also increased the erosivity that also led to remobilization of midchannel bars along with the uprooted trees. In the downstream (southern mountain front), maximum damage was caused by activating seemingly dormant ephemeral tributary channels. The slope-channel coupling locally bulked the sediment supply of the trunk river. The disaster was force amplified when the river was temporarily obstructed by the manmade structures (e.g., suspension bridges), and most importantly, urban settlements (largely hotels) on the flood plain. Also, many public buildings suffered as these were constructed in/along the ephemeral tributary channels, which were temporarily blocked by these structures, as well as by logged tree trunks. The Beas flood is yet another brutal reminder to change our perception towards the developmental approach, given that extreme events are projected to increase in the Himalaya. [ABSTRACT FROM AUTHOR]

This paper introduces a new accelerating algorithm, efficient match slimmer (EMS), specifically designed to lighten computational loads of sophisticated template matching algorithms, enabling these algorithms to be effectively run on single‐board computers. Utilizing EMS in conjunction with a robust template matching algorithm, we have developed Raspberry Vision—a compact, cost‐effective, and real‐time vision‐based system. Its compactness and portability facilitate a practical measurement strategy that not only minimizes the camera‐to‐target distance but also simplifies the camera calibration process in bridge displacement monitoring, thereby enhancing measurement accuracy. The performance of the system is estimated on two operational suspension bridges. The results demonstrate that Raspberry Vision, equipped with the measurement strategy, can significantly improve the measurement accuracy in the long‐span bridge test and is also suitable for cross‐sea bridge measurements. [ABSTRACT FROM AUTHOR]

The First Egongyan Bridge in Chongqing, China was opened to traffic on December 27, 2000. It carries six-lanes of city traffic and two pedestrian paths, one on each side. It is a 600 m span suspension bridge. It was planned that the two pedestrian paths might eventually be converted to transit tracks in the future. However, with the rapid increase in urban traffic, the deck was transformed into an 8-lane bridge instead. Therefore, a new bridge parallel and adjacent to the old bridge was built for the rail transit. For aesthetic reasons, the city decided that the new bridge should also be a suspension bridge, with the same span length and tower height as the first bridge. The First Egongyan Bridge was a true suspension bridge with main cables anchored to ground anchors. However, the new bridge bridge's proximity to the first bridge necessitated the construction of a self-anchored suspension bridge that did away with a second set of ground anchors. This 600 m span happened to be the world's longest span for a self-anchored suspension bridge. [ABSTRACT FROM AUTHOR]

A long-span double-deck steel truss suspension bridge is easy to produce vortex-induced vibration (VIV) at low air velocity, which affects bridge service life. Additional aerodynamic measures play a role in suppressing VIV by changing the aerodynamic shape, which is a common control method. As the main aerodynamic measure to suppress the VIV response, wind fairing is widely used in engineering practice. In order to obtain the optimal additional position and shape parameters of the fairing, Huangjuetuo Yangtze River Bridge is the research target. Through the combination of a wind tunnel test and numerical simulation, the VIV response of the original and fairing section is studied. Based on data analysis, it is revealed that these additional fairings to the upper chord can significantly reduce the VIV response. When the shape parameters of the fairing are h/D = 1/4 and l/D = 1, the VIV inhibition efficiency is the highest, which can reach 65.51%. By analyzing the flow distribution, it can be seen that VIV is caused mainly by vortex separation in the upper bridge board area. Although this wind fairing does not change the original vortex shedding forms, it changes the first separation point and movement direction of the airflow, making the vortex scale generated by the airflow smaller and the vorticity lower, thus effectively suppressing VIV. [ABSTRACT FROM AUTHOR]

In the actual structural health monitoring system of suspension bridges, only part of suspenders tension can be monitored, but not all the suspenders tension can be obtained. To solve this problem, a method for suspenders tension identification of bridges based on the spatio‐temporal correlation between the girder strain and suspenders tension is proposed. By using actual monitoring data of vehicle loads, a spatio‐temporal correlation model of the girder strain and tension forces of all suspenders is constructed based on the combined application of stacked denoising autoencoder and convolutional neural networks‐long short‐term memory model, so as to realize the preliminary identification of suspenders tension. On this basis, by using the actual monitoring data of suspenders tension and the strain monitoring data obtained through the distributed optical fiber sensors, the delicate identification of tension forces of all suspenders is realized based on the error interpolation of preliminary identification results. The results of the example bridge show that the method in this paper can effectively identify tension forces of all suspenders of the suspension bridge, and identification results are more accurate than the method using only the monitoring data of suspenders. [ABSTRACT FROM AUTHOR]

Form-finding is an essential task in the design of efficient lightweight structures. It is based on the crucial assumption of one single shape-determining load case, usually represented by self-weight. Adaptive components integrated into the structure open a way to even more efficient lightweight designs, as such structures can adapt their shapes to varying external loads and redistribute internal forces. This article presents a method for form-finding of adaptive truss structures subject to multiple, independently acting load cases, also incorporating possible design constraints. To ensure the consistency of the manufacturing lengths of passive elements in all load cases, special constraints are considered. The method enables to reduce sensitivity of the structural shape with respect to various different loads by means of actuation to meet design and serviceability requirements with a lower structural mass compared to conventional design strategies. This is demonstrated within a replaced real-world-like setting of an adaptive suspension truss bridge. [ABSTRACT FROM AUTHOR]

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

The 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]

In this manuscript, we study a thin and narrow plate equation that models the deck of a suspension bridge that is subject to a Balakrishnan-Taylor damping and a strong damping. First, by using the Faedo Galerkin method, we prove the existence of both global weak and regular solutions. Second, we prove the exponential stability of the energy for regular solutions by combining the multiplier method and a well-known result of Komornik. [ABSTRACT FROM AUTHOR]

The main bridge of Wanlong Bridge under construction is the first spatial self anchored suspension bridge with elliptical steel tower in the world. The saddle of this bridge adopts an self-adaptive space cable saddle combined with casting and welding, which has the following technical difficulties: the force of space cable saddle is complex. The longitudinal stiffness of the elliptical tower is large, and the slip resistance of the main cable saddle is prominent. The bottom of the saddle is a flexible support, the cable saddle and the main tower are co-deformed, and the tower-saddle connection structure is complicated in force transmission. In order to master the key technology of the main cable saddle and the tower-saddle connection structure of the self-anchored suspension bridge with elliptical tower and space cable, this paper carries out a systematic study by using numerical analysis method. The research conclusions are as follows: (1) When the bridge is subjected to (dead load+car+crowd+tap water+temperature+wind), the minimum friction coefficient µ that satisfies the requirements is 0.215, and the 12 mm vertical friction plates are required. (2) The maximum Von Mises stress and maximum vertical deformation of the main cable saddle under the condition of maximum cable force are 186.2 MPa and 1.572 mm, which meet the requirements of strength and stiffness. (3) In the structure connecting the main cable saddle and the steel tower, the force of the main cable saddle is transferred to the web of the steel tower in the form of vertical shear force through the supporting baffle. The shear force of the supporting baffle at the end is significantly greater than that of the middle baffle, and the non-uniformity coefficient of shear transfer is 1.29. (4) The support plate of the main cable saddle has a certain angle at the edge of the saddle area. The maximum longitudinal angle under the condition of empty cable is 0.366‰ rad, which should be taken into consideration in the saddle pushing construction. [ABSTRACT FROM AUTHOR]

The completed bridge alignment of super long-span railway bridges is prone to large deviation from the design alignment, which leads to the unrealization of the original rail surface design alignment, and it is usually necessary to change the rail surface alignment on the basis of the completed bridge alignment. In order to ensure that the changed rail surface alignment meets the requirements of train operation performance, it is particularly important to reasonably evaluate the completed bridge alignment of long-span railway bridges before laying the track. In this paper, the characteristics of the measured completed bridge alignment of a long-span railway bridge in China are analyzed. Combined with the adjustable capacity of ballast bed on the bridge, an evaluation method of completed bridge alignment of long-span railway bridges based on riding quality is proposed, and the amplitude of completed bridge alignment within the sensitive wavelength range of the vehicle body is taken as the evaluation index. Firstly, according to the evaluation principle that the vertical acceleration of vehicle body caused by line random irregularity, additional deformation of bridge under external loads and rail surface alignment does not exceed level I management standard, the maximum acceleration caused by rail surface alignment within the sensitive wavelength range of vehicle body is determined. Then the correlation between vertical acceleration of vehicle body and chord measurement amplitude, and the correlation between chord measurement amplitude and linear amplitude are studied to determine the maximum amplitude of rail surface alignment within the sensitive wavelength range of vehicle body. Finally, by deducing the correspondence between rail surface alignment amplitude and completed bridge alignment amplitude within the sensitive wavelength range of the vehicle body, the limit value of the evaluation index is formulated. Taking a kilometer-level suspension bridge in China as an example, the limit value of the evaluation index is determined to be 58 mm according to the method of this paper. The maximum value of the measured completed bridge alignment within the sensitive wavelength range of the vehicle body of this bridge is 36 mm, which does not exceed the limit value, indicating that the control effect of the completed bridge alignment is good, and on the premise of meeting the requirements of ballast bed thickness, the rail surface alignment which meets the riding quality can be laid on the basis of the completed bridge alignment. [ABSTRACT FROM AUTHOR]

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

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

Hybrid cable-stayed suspension (HCSS) bridges enjoy broad application prospects due to their excellent stability and economic benefits. The mechanical response of the transition section between the two subsystems of this novel bridge type is a common concern in the design and use stages. This paper took the design scheme of an HCSS bridge with a main span of 1440 m as the research object. A global finite element model (FEM) of the example bridge and local finite element models of the transition section were established, and the mechanical performance of the subsystem and components of the transition section was investigated. Moreover, parametric studies were conducted to investigate the influences of varies structural parameters on the mechanical performance of the transition sections of HCSS bridges. The results show that the mechanical behavior suddenly changes significantly at the transition between the cable-stayed section and the suspension section. Performance mutations in the transition section of a HCSS bridge can be improved by changing structural parameters, such as the transition section length, the number of cross cables, the area of the outermost cables, and the distance between the outermost cables and adjacent cables. The present findings may provide a reference for the better understandings and design of HCSS bridges. [ABSTRACT FROM AUTHOR]

Cable force estimation of the suspenders is of tremendous significance for the safety and condition evaluation of arch bridges. The modern suspender cable structure widely used nowadays calls for an efficient and robust estimation method accounting for the cable bending stiffness, complex boundary conditions, intermediate dampers, and variable suspender segments. To estimate the tension force in arch bridge suspenders, this paper proposes an exact analytical method that can simultaneously consider the aforementioned factors for the first time. Based on a generalized suspender cable model including all these factors, the transcendental equation for cable force calculation was obtained from the determinant of a 4 × 4 matrix derived using the transfer matrix method. Due to the low dimensionality of the matrix, the transcendental equation size is largely reduced. This allows rapid cable force calculation without requiring complicated numerical iteration algorithms. A dimensionless parametric analysis was conducted to investigate the impact of various factors on the frequency parameter of the suspenders. Subsequently, the efficacy of the proposed method was verified, and an extensive estimation error analysis was performed using finite elements. Moreover, the method was applied to four real-world bridges with measured vibration frequency available. The results showed that the method can accurately estimate the tension force in suspenders with flexural rigidity, arbitrary boundary conditions, and any number of intermediate dampers and nonuniform segments. The proposed method can also be used for suspender cable force estimation of other cable-supported bridges, such as suspension bridges. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the asymptotic behavior of a linear problem that describes the vibrations of a coupled suspension bridge. The single-span road-bed is modeled as an extensible thermoelastic damped beam, which is simply supported at the ends. The heat conduction is governed by Cattaneo's law. The main cable is modeled as a damped string and is connected to the road-bed by a distributed system of one-sided elastic springs. First, utilizing the theory of semigroups, we prove the existence and uniqueness of the solution. Second, by constructing an appropriate Lyapunov functional, we establish exponential stability using the energy method. Numerically, we introduce fully discrete approximations based on the finite-element method to approximate the spatial variable and the implicit Euler scheme to discretize the time derivatives. Then, we show that the discrete energy decays, and a priori error estimates are established. Finally, some numerical simulations are presented to show the accuracy of the algorithm and the behavior of the solution. [ABSTRACT FROM AUTHOR]

Ensuring the safe operation of suspension bridges is paramount to prevent unwanted events that can cause failures. Therefore, it is crucial to continuously monitor their operational status to uphold safety and reliability levels. However, natural deterioration caused by the surrounding environment, primarily due to corrosion, inevitably impacts these structures over time, particularly the main cables made of steel. In this study, a robust framework is proposed to predict the annual corrosion rate in main cables of suspension bridges, while investigating the impact of the surrounding environmental factors on this process. To do so, the implementation of four regression models and four machine learning techniques are used in the first phase for modeling the annual corrosion rate based on a comprehensive database containing various environmental factors. The modeling performance is evaluated through a range of statistical and graphical metrics. After that, Shapley Additive Explanations (SHAP) is utilized to explain the model and to extract the impact of each variable on the final modeling results. Overall, the findings demonstrate the effectiveness of the proposed framework for addressing this issue. The Extreme Gradient Boosting (XGB) emerged as the top-performing model, achieving an overall R2 of 0.982. Moreover, the SHAP findings highlight the impact of CL− on the annual corrosion rate as the factor with the highest influence during the modeling process. The high performance of the proposed model suggests its potential utility in further research concerning the reliability of suspension bridge main cables.