Dynamic Response Of Cable-stayed Bridge Research Articles

Dynamic response of cable-stayed bridge under wind-wave-current action considering pile-soil interaction

Sea-crossing bridges are generally subjected to the combined wind, wave and current action, making it worthwhile investigating the dynamic response of cable-stayed bridges under wind-wave-current action. In this study, the numerical wave flume is utilised to obtain wave-current action, where a measured spectrum is applied to generate random waves. The stochastic wind field is calculated through the spectral representation model. These actions are validated by comparing experimental and theoretical results. A comparative analysis under different loads provides the theoretical basis for load type determination. The influence of pile–soil interaction is also studied with the consolidation, pile–soil solid contact (PSSC), and soil spring model. The results show that the root mean square (RMS) values of girder displacement are greater under regular wave-wind-current action, while the extreme values of the girder internal force present the opposite pattern due to the statistical characteristics of random waves. It indicates that the statistical characteristics of random waves should be considered to secure the girder safety. For the bridge tower, the random wave-wind-current action has a greater effect on the lateral displacement responses. Furthermore, the model considering the pile–soil interaction gets more flexible, absorbing more energy of low-frequency wave-wind-current action.

Dynamic response and parameter analysis on the vehicle–bridge coupling of cable-stayed bridge under over-limit transportation

PurposeOver-limit transportation has the characteristics of large axle load, large number of axles and lateral distribution width. Under the action of over-limit load, the coupling vibration effect of vehicle–bridge is more obvious, and the deformation of bridge components is large. Thus, research and analysis of the vehicle–bridge coupling dynamic response of long-span bridges under over-limit transportation has practical engineering significance.Design/methodology/approachBased on the principle of invariable elastic potential energy, this paper derives dynamic model of over-limit transportation n-axis flat vehicle. The numerical simulation method is used to model and calculate a cable-stayed bridge, and the static effect of the cable-stayed bridge and the dynamic response of vehicle–bridge coupling under different parameters are compared and analyzed.FindingsThe focus is on the influence of vehicle load and vehicle velocity parameters on the stress and amplitude of different cables under over-limit transportation, and the corresponding variation law is obtained.Originality/valueThe research on the coupled dynamic response of cable-stayed bridges has attracted the attention of many scholars, but there are relatively few studies on the coupled vibration of out-limit vehicles and bridges. In this paper, based on finite element software, a vehicle–bridge coupling model under bulk transportation is established.

Dynamic response of cable-stayed bridges due to sudden failure of stays: the 3D problem

This paper studies analytically the problem of the sudden failure of a number of stays through a suitable mathematical model, based on the analytical method exposed by authors in previous publications and extended in this study through a 3D analysis. The analysis is carried out by the modal superposition method, and the gathered equations of the problem are solved through the Galerkin procedure and the Duhamel’s Integrals. Characteristic examples are solved and useful diagrams and plots are drawn, while interesting results are obtained.

Dynamic response of cable-stayed bridge under blast load

Over the past two decades, blast loads have been recognised as one of the extreme loading events that must be considered in the design of important structures such as cable-stayed bridges. However, design provisions for blast-resistant bridges are very limited and mostly empirical owing to an inadequate understanding of the local and global dynamic response of the bridge components (piers, deck and cables) subjected to blast loading scenarios. Accordingly, this study develops detailed finite element models of a steel cable-stayed bridge and it is analysed using an explicit solver. Three different explosive sizes, i.e. small (01W), medium (04W) and large (10W), are considered (W being the TNT equivalent explosive weight index) and placed at different locations above the deck level to determine the influence of the size and location of the blast loads on the global and local response of the bridge components. In particular, the results of the computer simulations are employed to characterise the type and extent of damage on the pylon and deck, and additionally to investigate the potential cable loss scenarios associated with a loss of anchorage. Furthermore, the results of the finite element simulations are used to assess the potential progressive collapse response of a cable stayed bridge subject to various blast loading scenarios.

Identification of horseshoes chaos in a cable-stayed bridge subjected to randomly moving loads

In this paper, the dynamic response of cable-stayed bridge loaded by a train of moving forces with stochastic velocity is investigated. The cable-stayed bridge is modelled by Rayleigh beam with linear elastic supports. The stochastic Melnikov method is derived and the mean-square criterion is used to determine the effects of stochastic velocity and cables number on the threshold condition for the inhibition of smale horseshoes chaos in the system. The results indicate that the intensity of the random component of the loads velocity can be contributed to the enlargement of the possible chaotic domain of the system, and/or increases the chances to have a regular behavior of the system. On the other hand, the presence of cables in cable-stayed bridges system increases it degree of safety and paradoxically can be contributed to its destabilization. Numerical simulations of the governing equations are carried out to confirm the analytical prediction. The effect of loads number on the system response is also investigated.

Dynamic response of cable-stayed bridges subjected to sudden failure of stays - the 2D problem

A significant problem met in engineering practice when designing cable-stayed bridges is the failure of cables. Many different factors can lead to sudden failure of cables, such as corrosion, continuous friction or abrasion, progressive and extended crevice created by fatigue and finally an explosion caused by sabotage or accident, are some of the causes that can lead to the sudden failure of one or more cables. This paper deals with the sudden failure of cables in a special form of cable-stayed bridges with a single line of cables anchored at the central axis of the deck's cross-section. The analysis is carried out by the modal superposition technique where an analytical method developed by the authors in a previous work has been employed.

Dynamic response of cable-stayed bridges subjected to sudden failure of stays - the 2D problem

Dynamic response of cable-stayed bridges subjected to sudden failure of stays - the 2D problem

Time-History Analysis of Lowpylon Cable-Stayed Bridge with Moving Loads

Established space dynamic analysis model of nonlinear structure in accordance with the unique mechanical characteristics of Lowpylon Cable-stayed Bridge. As the Example for the program about 90+128 meters spacing lowpylon Cable-stayed Bridge of houhu in Wuhan,Simulated the whole process of automobile loading bridge ,calculated eigenvalues of moving loads. Adopted computing skills,using nonlinear supperposition theory analysed time-history and discussed the influence about vibration of transverse and longitudinal because of different velocity. The results show that the research using nonlinear supperposition method to study the dynamic response of Cable-stayed Bridge under moving load is reasonable and effective.

Vibration control of cable-stayed bridges—part 1: modeling issues

The objective of the research presented here is to increase the understanding of how the complexities associated with modeling cable-stayed bridges, such as non-linear behaviour and the participation of highly coupled, high-order vibration modes in the overall dynamic response, affect the overall effectiveness of active control schemes. The 316-degree-of-freedom analytical model studied here is based on the Jindo Bridge located in South Korea. Computational considerations associated with control analyses require the size of the model to be significantly reduced, without loss of the important vibration characteristics and complexities. Three separate reduced-order modelling techniques for creating effective control models are studied here: the IRS method, the internal balancing method, and a modal reduction method. These methods are studied and compared on their ability to capture the complex dynamic response of cable-stayed bridges subjected to multiple-support excitation and their ability to create viable and computationally sound state-space models for control analyses. Results show that the modal reduction technique, because of the ability to select only those modes causing the largest force and displacement response, is most effective for control applications. © 1998 John Wiley & Sons, Ltd. Language: en

Dynamic Response of Cable-Stayed Bridges under Moving Loads

A modeling method for cable-stayed bridges with nonlinear cables that is used for the dynamic response under moving loads is discussed in this paper. Individual stay cables are modeled by short catenary cable elements in which the nonlinearity due to large displacements but small deformations and the nonlinearity due to the variations of tension are taken into account. A linear approximate bridge model is used to solve the dynamic response of cable-stayed bridges; the nonlinear contribution of the stay cables is added by means of an iterative procedure. Internal nodes of stay cables are not present in the linear approximate bridge model so that it contains a small number of degrees of freedom (DOF), whereas the nonlinear dynamic response of stay cables is computed at cable level, one at a time, by means of the finite-element method using many internal nodes for each stay cable. An illustrative example demonstrates that the proposed method is very efficient, inexpensive, and capable of exhibiting the resonance of stay cables excited by the bridge deck and towers.

Dynamic response of cable-stayed bridges to moving vehicles using the structural impedance method

The importance of dynamic interactions between cable-stayed bridges and heavy moving vehicles, such as trucks and locomotives, has been recognised by bridge engineers for a long time. A structural impedance algorithm is developed for analysing the dynamic response of cable-stayed bridges subjected to traversing vehicles. The bridge deck is modelled as an elastic plate, and the cables are idealised as springs for simplicity. The vehicles are modelled as a series of masses with suspension systems moving with different speeds and accelerations. A comprehensive computer program, CABLESIM, is developed for the static and dynamic analyses of a cable-stayed bridge. The accuracy of the numerical procedure and its computer implementation is verified with the available analytical and experimental results. A parametric study is conducted to investigate the effects of vehicle velocity, girder depth, different types of cable arrangements, and traffic load on the dynamic response of the deck. The numerical results are expected to be important in assessing the dynamics of cable-stayed bridge components and in determining the safety and allowable traffic conditions.