Cable Displacement Research Articles

The Tolerance Interval Optimization of Cable Forces During the Construction Phase of Cable-Stayed Bridges Based on Hybrid Intelligent Algorithms

To investigate the controllability of sensitive cable forces during the construction phase of cable-stayed bridges, a novel optimization method is proposed, based on BP neural networks, which combines Gaussian process prediction with a simulated annealing-optimized particle swarm algorithm to determine the tolerance intervals of construction cable forces. Based on the analysis results of multiple linear regression, the variables for optimization are identified, and a mapping relationship between the sensitive cable forces and displacement values is established using a BP neural network. Subsequently, a Gaussian process model is constructed to delineate the relationship between cable forces and reliability, with a focus on the reliability of displacements during the construction phase of the cross-section, specifically targeting sensitive cable forces. Finally, a combination of the simulated annealing algorithm and the particle swarm algorithm is employed to optimize the tolerance intervals of the cable forces. To validate the effectiveness of the proposed optimization method, a case study is conducted on the tolerance interval optimization of cable forces using a three-tower steel box girder cable-stayed bridge. In this study, the construction cable forces are treated as optimization variables, while the reliability of displacements at both the main girder section and the tower’s top section serve as the optimization objectives and constraint conditions. Under the premise of ensuring structural reliability, the accurate tolerance range for the stay cable forces during the construction phase of the cable-stayed bridge is obtained. The results indicate that the traditional PSO algorithm stabilizes after 26 iterations, whereas the hybrid intelligent algorithm reaches stability after just 13 iterations. In addition, the hybrid algorithm shows a significant increase in the objective function value during early iterations, demonstrating stronger optimization capability. This indicates that the optimization method exhibits better convergence and superior global optimization capability. It effectively improves the compatibility and controllability of the cable-stayed bridge construction process while simplifying the computational process.

Analytical Formulation and Optimization of the Initial Morphology of Double-Layer Cable Truss Flexible Photovoltaic Supports

With the rapid development of the photovoltaic industry, flexible photovoltaic supports are increasingly widely used. Parameters such as the deflection, span, and cross-sectional dimensions of cables are important factors affecting their mechanical and economic performance. Therefore, in order to reduce steel consumption and cost and improve application value, it is crucial to design and optimize their initial morphology. In this paper, the mechanical behavior of a single-cable structure is introduced, and the simplified analytical formulations for internal force and displacement are deduced based on the geometric nonlinear characteristics and small strain assumption of the flexible photovoltaic supports. On this basis, the analytical expressions for the cable force and displacement of a convex prestressed double-layer cable truss flexible photovoltaic support structure under a uniform load are derived, and the correctness of the analytical formulations is verified by comparing the values with the finite element analysis results. In order to reduce the construction costs of the flexible photovoltaic support, a mathematical model for optimizing the initial structure’s morphology is established according to the analytical formulations. The initial morphology of the double-layer cable truss flexible photovoltaic support is optimized, and the optimization results of different deflection deformation limits and whether the lower load-bearing cable is allowed to relax are compared. The results indicate that the errors of the displacement formulation and cable force formulation, when compared with the finite element results, are less than 3% and 4%, respectively, which verifies the accuracy of the analytical formulations. By analyzing the cable force and displacement of the structure under static action, it is suggested that the deflection limit of the double-layer cable truss structure should be 1/100 of the single span. The lower load-bearing cables of the double-layer cable truss flexible photovoltaic support are highly susceptible to relaxation under wind suction loads, and, by comparing the optimization results, it is suggested that slack should be allowed in the lower load-bearing cables for a better economic effect. When choosing the most economical structure morphology, it is recommended that the total height of the mid-span struts should be 1/20~1/15 of the single span. The analytical formulation and the mathematical model for the optimization of the initial morphology proposed in this paper can provide certain theoretical references and bases for the design of practical engineering projects and play an important role in promoting its application and promotion.

HSC-RSW with laterally installed XADAS dampers: Seismic performance

This study investigates the seismic behavior of high-strength concrete (HSC) rocking shear walls (RSW) equipped with X-shape Adding Damping and Stiffness (XADAS) dampers installed perpendicular to the wall via brackets. Unlike previous studies where dampers are integrated along the wall length, this research leverages the advantages of HSC to minimize sectional dimensions while employing laterally installed XADAS dampers to enhance the cyclic response, yielding flag-shaped hysteresis curves. The alignment angle of the XADAS dampers is also considered a crucial variable in assessing the overall seismic performance of the proposed HSC-RSW system. A novel constructional approach using brackets to install lateral XADAS dampers is implemented. Post-tensioning (PT) forces are applied as consistent axial strains in cables, achieved through predefined cable support displacements. A macro-FEM model is developed to validate the chosen experimental reference test and is subsequently used for further parametric studies. The parametric studies indicate that increasing concrete compressive strength (CCS) enhances the self-centering capability by reducing RSW strains and facilitating rocking. Additionally, incorporating XADAS dampers into the system improves energy dissipation, with a zero-degree alignment angle identified as optimal. Notably, the modeled HSC-RSW systems exhibit limited drift capacity (less than 2 %) compared to normal strength concrete (NSC)-RSW systems, where wall toes are conventionally prone to crushing.

Numerical study on the dynamic pressure control for self-forming roadways using CHRCT in thin coal seams with thick and hard roofs

Close-hole roof-cutting technology (CHRCT, also called “dense drilling”) has been widely applied in coal mines due to its economic and safety benefits. Inappropriate cutting parameters and support schemes can lead to dynamic pressure disturbances in self-forming roadways with thick and hard roofs. Moreover, fully characterizing the procedure and process of self-forming roadways using CHRCT in the field is difficult, resulting in unconvincing results. Therefore, this study aims to fill the gaps in theoretical knowledge and methodology. First, the dynamic pressure characteristics of the self-forming roadway using CHRCT were investigated, and the dynamic pressure types of the roadway were classified. There are three main types: roof cut off along the coal wall side of, severe deformation, and overhanging roof of a roadway after the second working face mining. The effects of different hole parameters (inclination angle, depth and spacing) on the roof cutting to form a roadway were also investigated. The optimal hole inclination, depth and spacing of 15°, 8 m, and 200 mm were determined through a series of experiments. Then, three support schemes embedded in the roadway were compared in terms of stress evolution, bolt and cable axial forces, roof displacement, and structure. Finally, this study proposes a dynamic pressure mitigation strategy through the optimization of parameters for close-hole roof-cutting and support schemes, monitoring and controlling ground pressure in roadways, and taking auxiliary measures for pressure relief. The results show that this strategy can effectively eliminate the dynamic pressure of the roadway and meet the stability requirements of the full mining cycle. This paper presents a methodology for analysing CHRCT via numerical simulation. Moreover, this approach is of great theoretical and practical importance for dynamic pressure control for self-forming roadways using CHRCT in thin coal seams with thick and hard roofs.

Investigation of mechanical behaviors of spoke-wheel cable structures through experimental and numerical analysis driven by digital-twin

Ascertaining the mechanical behaviors of large-scale space structures (e.g. spoke-wheel cable structure) is essential for guaranteeing their structural safety. This study proposed a digital-twin (DT)-based method for analyzing the mechanical behaviors of spoke-wheel cable structures. A spoke-wheel cable structure with a span of 6 m was used as a case study to validate the proposed method. The structural behaviors, such as cable forces and structural displacements under five loading conditions (i.e. dead load and dead load plus 3/10, 5/10, 8/10 or full-areal live load), were investigated experimentally and numerically. A comparative analysis was conducted to compare the results using the proposed method with the traditional method. Results show that the proposed DT method could help to update geometric details and boundary conditions of the twin model for ensuring effective numerical analysis. Moreover, the changing trends of general force for the same type of cables were basically the same under different loading conditions. Besides, the forces of upper spoke cables and inner-ring decreased under the action of live load, whereas the forces of lower spoke cables and inner-ring increased. The displacement directions of loaded and unloaded nodes were downward and upward, respectively, when subjected to uneven live loads. In addition, the vertical displacements of the outer nodes were greater than thoseof the inner ones. Furthermore, the cable forces and displacements of the structure changed more obviously under the action of asymmetric load. The established high-fidelity DT model could support effective numerical analysis of mechanical behaviors of large-scale space structures.

The CathEye: A Forward-Looking Ultrasound Catheter for Image-Guided Cardiovascular Procedures.

Catheter based procedures are typically guided by X-Ray, which suffers from low soft tissue contrast and only provides 2D projection images of a 3D volume. Intravascular ultrasound (IVUS) can serve as a complementary imaging technique. Forward viewing catheters are useful for visualizing obstructions along the path of the catheter. The CathEye system mechanically steers a single-element transducer to generate a forward-looking surface reconstruction from an irregularly spaced 2-D scan pattern. The steerable catheter leverages an expandable frame with cables to manipulate the distal end independently of vessel tortuosity. The tip position is estimated by measuring the cable displacements and used to create surface reconstructions of the imaging workspace with the single-element transducer. CathEye's imaging capabilities were tested with an agar phantom and an ex vivo chronic total occlusion (CTO) sample while the catheter was confined to various tortuous paths. The CathEye maintained similar scan patterns regardless of path tortuosity and was able to recreate major features of the imaging targets, such as holes and extrusions. The feasibility of forward-looking IVUS with the CathEye is demonstrated in this study. The CathEye mechanism can be applied to other imaging modalities with field-of-view (FOV) limitations and represents the basis for an interventional device fully integrated with image guidance.

Optimal Cable Force Adjustment for Long-Span Concrete-Filled Steel Tube Arch Bridges: Real-Time Correction and Reliable Results

For complex structures, the existing optimization method for suspender cable forces involves extensive matrix operations during the solution process, requiring high computational power and time. As a result, obtaining a more accurate solution becomes challenging. To address this issue and improve the stress distribution of suspenders in the completed state, while minimizing the need for frequent cable force adjustments and grid beam elevation changes during construction, a novel method for cable force optimization is proposed. In this study, the Pingnan Third Bridge, which is the world’s longest large span arch bridge with a span of 575 m, is taken as the engineering background. This study combines finite element analysis and multi-objective optimization methods to develop a cable force optimization approach for real-time correction during the panel girder lifting of long-span concrete-filled steel tube (CFST) arch bridges. The optimization method involves treating the panel girder weight and displacement during construction as parameter variables, and considering the displacement and unevenness of the panel girder in the completed state as constraint conditions. The objective equation is defined based on the displacement and cable force during the lifting construction process and, through optimization, the cable forces and displacements of each lifting section are calculated. The results demonstrate the feasibility of integrating optimization theory into the cable force optimization process during panel girder lifting. In this study, we have taken into account the characteristics of real-world engineering and focused on specific key points to reduce the order of the influence matrix. Consequently, the computational costs are reduced, facilitating the development of a multi-objective tension optimization program. By minimizing segment displacement variations and ensuring even cable force distribution in the completed state, the method ensures that the bridge meets the required completion requirements without the need for repetitive iterations or cumbersome calculations. It provides higher optimization efficiency and superior outcomes, offering significant value for cable force calculations during suspender construction of similar bridge types and guiding construction processes.

Dynamic Response Measurement and Cable Tension Estimation Using an Unmanned Aerial Vehicle

Since all structures vibrate due to external loads, measuring and analyzing vibration data is a representative method of structural health monitoring. In this paper, we propose a non-contact cable estimation method using a vision sensor mounted on an unmanned aerial vehicle. A target cable among many cables can be identified through marker detection. In addition, the motion of the structure can be quickly captured using the extracted feature points. Although computer vision can be used to transform displacements of multiple axis, in this study, only the vertical displacement is considered to estimate tension. Finally, the cable tension can be estimated via the vibration method using the modal frequencies derived from the cable displacement. To verify the performance of the proposed method, lab-scale experiments were carried out and the results were compared with the conventional method based on the accelerometer. The proposed method showed a 3.54% error compared with the existing method and confirmed that the cable tension force can be estimated quickly at low cost.

Frequency calculation method and wind-induced dynamic response of cable net façades considering the façade stiffness

In this study, a frequency formula for cable net façades that considers façade stiffness is proposed, and the effect of the façade stiffness on the dynamic behavior is analyzed. Initially, a theoretical formula based on membrane theory is derived for calculating the frequency of cable net façades while neglecting façade stiffness. Moreover, a total of 720 detailed finite element (FE) models of cable net façades with various parameters are established in ANSYS finite element software. The effects of glass thickness, cable spacing and cable force on frequency are analyzed with the detailed FE models. Based on the theoretical formula and detailed FE models, a fitted frequency formula that includes the façade stiffness is further proposed to calculate the first-order mode, which is the prominent mode. Furthermore, the effect of the façade stiffness on the dynamic response of the structure, including the cable force and displacement, is researched under excitation by wind loads based on time history analysis. The results show that the influence of façade stiffness on the frequency and dynamic response gradually decreases as the number of cable net grids increases. When the grid number is above 10, the impact can be ignored. In addition, the fitted formula can be used when the grid number is under 10, and when the number of grids exceeds 10, the theoretical formula can be applied. Considering this simplification, a simplified FE model is proposed in engineering design for grid numbers exceeding 10. When the grid number is less than 10, it is recommended to adopt a detailed FE model designed to avoid errors in structural design.

Analytical model for reinforcement effect and load transfer of pre-stressed anchor cable with bore deviation

Anchors have been widely used in slope engineering, mining engineering and foundation pit engineering, but their stabilities are significantly affected by anchor cable bending which could be contributed by complicated geological conditions and technical limitations. Theoretical analysis in this paper leads to the establishment of the stress model for the bending anchor cable, and the mathematical expression of the relationship between the ultimate pull-out force and the curvature of the bending anchor cable. Numerical simulation is used to evaluate the effect of the anchor cable curvature on the reinforcement effect. The results suggest that the stress distribution and reinforcement effect are affected by different curvatures, the bigger curvature corresponds to the smaller deformation and the larger pull-out force. The rate of decrease in the anchor cable displacement with the burial depth is linearly related to the pull-out force. In addition, the anchor cable curvature affects the response of the surrounding rock mass to stress and strain: The greater the curvature, the larger the area of the responsive rock mass and the higher mobilization of the strength of the rock mass itself. The anchor cable curvature also influences the reinforcement effect of multiple anchor cables. The results are applied to foundation pit engineering, and it is found as follows: The appropriately bending anchor cable (00-0.50 of curvature) with the same length can make wall stress and deformation more reasonable, and better control foundation deformation; however, with the increase in curvature, the effective anchoring length and the anchor cable depth decrease, and the reinforcement effect declines. The study results can provide reference for anchorage engineering.

A Novel Scaffold-Reinforced Actuator With Tunable Attitude Ability for Grasping

Owing to high compliance, adaptiveness, and easy controllability, soft actuators are widely adopted in soft grippers to grasp irregularly shaped or fragile objects. The specific motions can be preprogrammed into the flexible and constrained structures of the actuator, which provides an inexpensive and convenient method for desired motions. However, most preprogrammed structures cannot change the constraints on the actuator to achieve different kinds of deformations, which limits the motion diversities of actuators. This article proposes a scaffold reinforcement mechanism, where rotatable scaffolds distribute on the surface of the soft structure. The orientation adjustments of the scaffolds can change the deformation constraint of the actuator, which results in different kinds of motions. Based on the scaffold reinforcement mechanism, a scaffold-reinforced actuator is proposed, which can achieve bending motion and complex helical motion in the 3-D space by properly adjusting the orientation of the scaffolds. In addition, both the kinematic and mechanical models are proposed to forecast the behavior of the actuator when driven by cable displacement or tension force. Experimental results verify the validity of the theoretical model, and the actuator can achieve an independent control of bending and helical motion, which can be adopted in applications where both high dexterity and flexibility are required.

Inversion of dynamic displacement response of cable in the whole field based on single vibration measurement

Aiming at the problem that the dynamic displacement at critical positions of the cable cannot be measured due to economic or difficult installation, this paper proposes a method to invert the dynamic displacement of the cable in the whole field by using the dynamic displacement of a single measuring point. The method can realize the inversion of the lateral dynamic displacement response (L-DDR) and angular dynamic displacement response (A-DDR). Firstly, the exact mode shape functions of the L-DDR and A-DDR, considering bending stiffness, sag, inclination angle, and boundary conditions, are derived from the cable vibration control differential equation. The exact mode shape functions are a closed-form solution; thus, it can accurately calculate the cable mode shape at any frequency in real time. Then, an inversion method of the dynamic displacement of the cable in the whole field is proposed based on the amplitude ratio of the exact mode shape. This method can be used to invert the dynamic displacement of the cable in the frequency domain and time domain. Finally, through a numerical simulation and an actual cable test, it is verified that the accuracy of the proposed method is satisfactory. The cable dynamic displacement components at modal and external load frequencies are the main contributors to the dynamic displacement of the cable.

A Novel Acceleration-Based Approach for Monitoring the Long-Term Displacement of Bridge Cables

The cables of the long-span bridge are usually featured as ultra-low frequency, hence making the acceleration unable to accurately capture the information, e.g. damping ratios, for assessing the cable state assessment and mitigating the excessive structural vibration. The displacement was approved to be more sensitive to the low-frequency vibration than the acceleration. However, there is still a lack of effective method to accurately monitor the long-term displacements of bridge cables using reference-free methods. To address this issue, this paper develops a novel acceleration-based approach for monitoring the long-term displacements of the cables of long-span bridges. In the monitoring scheme, recursive least squares method is utilized to conduct baseline correction in the time domain integration of acceleration. An adaptive band-pass filtering method considering cable vibration characteristics is used to eliminate noise, thus avoiding the difficulty of selecting the cut-off frequency by experience in traditional methods. A numerical test of an analytical cable model and a field experiment of the hanger of a full-scale suspension bridge are applied to the applicability and robustness of the developed method. Result shows that adaptive band-pass filter considering the vibration characteristics is suitable for estimating the displacements of the cables. The estimated displacements using the developed method agree well with the background truth in both time and frequency domains.

Analytic Solution to Longitudinal Deformation of Suspension Bridges under Live Loads

Live load of moving vehicles has a very important effect on the fatigue life of suspension bridges, which causes not only vertical deformation but also longitudinal deformation. In this study, a general analytical formulation for analyzing the quasistatic longitudinal displacement of suspension bridges under vertical live loads is developed, and the underlying deformation mechanism is revealed. First, the analytical vertical and longitudinal deformation equations for the single main cable subjected to live loads are formulated considering the geometric nonlinearity. Then, the relation of longitudinal displacements between the stiffening girder and the main cable for a single-span suspension bridge is established through analyzing the geometric configuration of deformed deck-suspender segment and imposing the null longitudinal force condition. The relation is further modified to incorporate the effect of central buckles (CBs). Compared with the finite-element (FE) prediction, the proposed analytical solution is quite accurate for both concentrated and distributed loads. It is found that the coupling of vertical and longitudinal displacement of main cables and the longitudinal constraint between the cables and girder, are responsible for the longitudinal displacement of the girder. The effects of sag-to-span ratio, CB, and inclined suspenders are studied. The longitudinal displacement of the girder can be reduced by about 20% when the sag-to-span ratio is varied from 1/9 to 1/11, and the CB with proper stiffness is more effective in reducing the longitudinal displacements. The proposed formulation can be conveniently applied for parameter optimization in the preliminary design stage so as to avoid tedious repetitive FE analysis.

Tension and Deformation Analysis of Suspension Cable of Flexible Photovoltaic Support under Concentrated Load with Small Rise-span Ratio

The suspension cable structure with a small rise-span ratio (less than 1/30) is adopted in the flexible photovoltaic support, and it has strong geometric nonlinearity. Based on the principle of energy, the increment of cable force and the change of cable displacement under concentrated force are derived for the suspension cable in an equilibrium state under uniform distributed load, and the equivalent bending stiffness of simply supported beam under bending is given. Considering the strain energy generated by cable force variation, the method presented in the paper has higher calculation accuracy for suspension cable structures with a small rise-span ratio, and includes the special case of a large rise-span ratio. An engineering example of flexible photovoltaic support with a span of 15m is calculated and analyzed, and then compared with the finite element calculation results. The results show that the calculation error is less than 1% when the rise is 0.4 m, and the calculation error is less than 3% when the rise is 1.5m. The calculation formula in the paper is simple and accurate, which can provide a reference for static analysis and structural design of flexible photovoltaic support.

Vibration suppression of a cable under harmonic excitation by a nonlinear energy sink

The application research of nonlinear energy sink (NES) on vibration suppression in many fields is a hot topic. In this paper, the vibration suppression mechanism of a nonlinear energy sink on a cable under a harmonic load is studied novely. First, the dynamic model of the cable-NES system under harmonic excitation is established. The partial differential Equations (PDEs) of motion governing the in-plane vibration of the cable-NES system are derived by Hamilton’s principle. Then, by considering the coupling effect among the first three in-plane modes of the cable, the ordinary differential equations (ODEs) of the coupled system are obtained applying Galerkin integral. The incremental harmonic balance (IHB) method is used to solve the nonlinear ordinary differential equations. Meanwhile, the stability of the solution is determined using Floquet theory. Finally, the primary resonances of the first and third in-plane modes of the cable are explored respectively, and the vibration mitigation performance of the NES and the wavelet transform of the cable displacement response are analyzed. The research results show that the NES has a significant effect on the dynamic behavior and vibration mitigation of the cable, especially, when the NES parameters are the same, the vibration mitigation effect of the NES on the primary resonance of the 3rd mode of the cable is better than that of the 1st mode.

Experimental Investigation of the Dynamic Behavior of Submerged Floating Tunnels under Regular Wave Conditions

Submerged floating tunnels (SFTs) are an innovative traffic structure for transportation in deep and long-distance ocean environments. SFTs have the risk of being subjected to wave action in the complex ocean environment. Therefore, in order to ensure the safety and stability of SFTs during their service, the dynamic behavior of an SFT subjected to the action of waves is experimentally investigated in this study. Based on the wave–current flume, a physical scale-model experiment of an SFT for studying the dynamic behavior of an SFT subjected to regular waves interactions is deeply and thoroughly explored. The results show that the wave outputs from the wave-making system are verified to be reliable. The influence of major load parameters on the dynamic behavior of the SFT are deeply and thoroughly explored. The effects of wave height and wave period on acceleration, wave pressure, anchor cable force and displacement in an SFT are discussed. This experimental study has theoretical and practical significant for SFT design and safety.

A novel numerical approach and experimental study to evaluate the effect of component failure on spoke-wheel cable structure

The component failure of spoke-wheel cable structures is a major concern among the present structural engineering community. This paper investigated the effect of component failure on the spoke-wheel cable structures through numerical and experimental studies. Firstly, a new simulation modification method was introduced based on the building information modelling (BIM) and three-dimensional laser scanning (3DLS). Then, the finite element (FE) simulation was carried out using the original or modified model and related to the experimental study on the component failure of a typical spoke-wheel cable structure. Breakages of the spoke cables, poles, and inner-rings were considered to evaluate their influences on the behaviour of the spoke-wheel cable structure. The accuracy enhancement brought by the novel approach based on BIM + 3DLS was demonstrated. Furthermore, the structural reliability analysis after the component failure based on the modified FE model was conducted. The result indicates that the breakage of the ring cable caused the collapse of the entire structure and the breakage of the lower spoke cable led to a negative reliability index indicating a structural failure as well. However, after breaking the upper spoke cable, the reliability index remained positive, although large displacements occurred at some nodes. In contrast, the breakage of the pole had a relatively small influence on the structure and did not cause the failure of the whole structure. Moreover, the method based on BIM + 3DLS could help to establish a more accurate simulation model and reduce the calculation errors of the cable force and structural displacement significantly.

MemoBox: A mechanical follow-the-leader system for minimally invasive surgery

With the increase in Natural Orifice Transluminal Endoscopic Surgery procedures, there is an increasing demand for surgical instruments with additional degrees of freedom, able to travel along tortuous pathways and guarantee dexterity and high accuracy without compromising the surrounding environment. The implementation of follow-the-leader motion in surgical instruments allows propagating the decided shape through its body and moving through curved paths avoiding sensitive areas. Due to the limited operational area and therefore the instrument size, the steerable shaft of these instruments is usually driven by cables that are externally actuated. However, a large number of degrees of freedom requires a great number of actuators, increasing the system complexity. Therefore, our goal was to design a new memory system able to impose a follow-the-leader motion to the steerable shaft of a medical instrument without using actuators. We present a memory mechanism to control and guide the cable displacements of a cable-driven shaft able to move along a multi-curved path. The memory mechanism is based on a programmable physical track with a mechanical interlocking system. The memory system, called MemoBox, was manufactured as a proof-of-concept demonstration model, measuring 70 mm × 64 mm × 6 mm with 11 programmable elements and featuring a minimum resolution of 1 mm. The prototype shows the ability to generate and shift complex 2D pathways in real-time controlled by the user.

On the mechanism of divergent cable movement: Contribution of the bistable flow activity in the critical flow regime

This paper studies the contribution of the bistable flow activity on the installation of incipient conditions to provoke divergent stayed-cable movement. The experiment consists of performing dynamic tests on a long (6.1 m) and genuine inclined and smooth-surfaced cable in a wind tunnel. The cable has an outer diameter of 0.219 m and is equipped with 128 pressure taps distributed on seven (7) rings. The range of the Reynolds numbers is covering the critical flow regime around a circular cylinder. The evolution of mean and instantaneous aerodynamic coefficients is discussed and Proper Orthogonal Modes of the pressure pattern are created. The results indicate that both transitory regimes in the critical flow regime could contribute to install cable instability incipient conditions. Seemingly, only the unsteady states in the critical flow regime appear to participate on imposing large cable displacement. The influence of the circularity defect on disturbing flow fields around the circular cylinder has also been confirmed. Furthermore, the bistable flow activity has been clearly identified to contribute strongly in the installation of large-amplitude wind-induced vibrations.