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Viscous dampers are commonly used in large span cable-stayed bridges to mitigate seismic effects and have achieved great success.

However, the nonlinear analysis on damper parameters is usually computational intensive and nonobjective. To address these issues, this paper proposes a simplified method to determine the viscous damper parameters for double-tower cable-stayed bridges. An empirical formula of the equivalent damping ratio of viscous dampers is established through decoupling nonclassical damping structures and linearization of nonlinear viscous dampers. Shaking table tests are conducted to verify the feasibility of the proposed method. Moreover, this simplified method has been proved in long-span cable-stayed bridges.

The feasibility of this method is verified by the simplified model shaking table test. This simplified method for determining the parameters of viscous dampers is verified in cable-stayed bridges with different spans.

This simplified method has been validated in cable-stayed bridges with various spans.

In this paper, taking a p-section girder cable-stayed bridge as an example, the construction monitoring and load test of the bridge are implemented.

In order to ensure the safety of cable-stayed bridge structure in construction and achieve the internal force state of the completed bridge, the construction process is monitored for liner and stress of the p-section girder, construction error and safety state during construction. At the same time, to verify whether the bridge can meet the design requirements, the static and dynamic load tests are done.

The results of construction monitoring show that the stress state of the structure during construction is basically consistent with the theoretical calculation and design requirements. The final measured stress state of the structure is within the allowable range of the cable-stayed bridge, and the structural stress state is normal and meets the specification requirements. The load tests results show that the measured deflection of the midspan section of the main girder is less than the theoretical calculation value. The maximum deflection of the main girder is 48.03 mm, which is less than 54.25 mm of the theoretical value, indicating that the main girder has sufficient structural stiffness. Under the dynamic load test, the natural frequency of the three spans of the bridge is less than the theoretical frequency.

This study can provide important reference value for the construction and maintenance of similar p-section girder cable-stayed bridges.

Over-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.

Based 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.

The 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.

The 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.

In order to replace the conventional human maintenance of cable‐stayed bridges, a robot is designed and constructed for tasks such as cleaning, painting and rust‐detecting.

Adopting a modular approach, two kinds of climbing mechanisms, plus a painting mechanism and a rust‐detecting method are designed.

A robot that can climb and maintain the cables of cable‐stayed bridges has been designed and constructed. It has been proved by experiment that the robot can overcome many disadvantages of conventional human bridge‐maintenance, and drastically improve efficiency, cost, and safety.

The robot is of industrial size, but a new mechanism requiring less installing time will be designed for the future.

The robot has been applied to cables of the Nanpu Bridge and Xupu Bridge in Shanghai. More than 80 cable‐stayed bridges and six suspension bridges have been built or are being constructed across large rivers in China alone. This gives an enormous potential market.

The cable maintenance robot developed in this paper is the world's first special robot for the cables of cable‐stayed bridges.

The complexities in strait-crossing cable-stayed bridge project are increasing the risks. This study aims to identify and analyze the significant and worth-considered construction risks of the first, biggest and longest spanned strait-crossing bridge project in Indonesia.

As many as 32 risk events were identified and determined as the risks that exist and can be represented in the Suramadu bridge project context. Data was collected through a design-based questionnaire disseminated to experts involved in the project as well as semi-formal interviews. Several quantitative methods were applied to analyze the significant risks, such as relative importance index, Spearman’s rank correlation test and Mann–Whitney U test.

The analyses reveal that “unexpected natural behavior” confirmed by both contractor and consultant parties is the most significant and crucial risk event. Another risk event found to be significant is the “delayed payment.” On the other hand, it is also found that several risks within the legal category are found to be less significant compared to other major risk events.

The results of the present research should be interpreted in the context of several limitations. Given these possible concerns regarding the generalizability of the findings, along with the relatively low rate of participants in the current research, additional studies are needed to provide a more complete picture of stakeholder perceptions who are involved directly in the construction environment as well as to identify more construction risks specifically in the large-scale bridge project.

This study has provided fundamental contributions to the body of knowledge and practical implication to promote and assist decision-makers toward developing a comprehensive risk assessment of a large-scale bridge project.

The analyses of outcomes and discussion, as well as the findings of this research, have shed light on the construction risks understanding, which contributes to delivering a theoretical framework for achieving large-scale bridge project success.

The existing methods for determining cable forces in cable‐stayed bridges constructed are based on assumption of complete determinacy of structural parameters. This is usually referred to as deterministic analysis. But in reality there are uncertainties in design variables. These uncertainties include geometric properties (cross‐sectional properties and dimensions), material mechanical properties (modulus and strength, etc), load magnitude and distribution, etc. Thus deterministic analysis cannot provide complete information regarding cable forces in cable‐stayed bridges constructed. The purpose of this paper is to determine cable forces in cable‐stayed bridges constructed under parametric uncertainty.

An efficient and accurate algorithm is proposed to determine the cable forces in cable‐stayed bridges constructed under parameter uncertainty. The proposed method is a hybrid method, consisting of the improved Monte Carlo simulation method and forward process analysis method.

The proposed algorithm can obtain more information about the cable forces at different construction stages than the commonly used deterministic method, and it provides an improved understanding of the cable forces in cable‐stayed bridges constructed with parameter uncertainties.

The values of this type of research are that: it developed an efficient and accurate algorithm for determining the cable forces in cable‐stayed bridges constructed under parameter uncertainty; and it provided an improved understanding of the cable forces in cable‐stayed bridges constructed with parameter uncertainties.

This study aims to research the development trend, research status, research results and existing problems of the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge.

Based on the investigation and analysis of the development history, structure form, structural parameters, stress characteristics, shear connector stress state, force transmission mechanism, and fatigue performance, aiming at the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge, the development trend, research status, research results and existing problems are expounded.

The shear-compression composite joint has become the main form in practice, featuring shortened length and simplified structure. The length of composite joints between 1.5 and 3.0 m has no significant effect on the stress and force transmission laws of the main girder. The reasonable thickness of the bearing plate is 40–70 mm. The calculation theory and simplified calculation formula of the overall bearing capacity, the nonuniformity and distribution laws of the shear connector, the force transferring ratio of steel and concrete components, the fatigue failure mechanism and structural parameters effects are the focus of the research study.

This study puts forward some suggestions and prospects for the structural design and theoretical research of the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge.

The purpose of this paper is to provide a variety of viewpoints to illustrate the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges, which is validated by a symmetrical structure.

Based on the smooth and convergent bridge shapes obtained by the initial shape analysis, the one-element cable system (OECS) and multi-element cable system (MECS) models of the symmetric harp cable-stayed bridge are developed to verify the applicability of the analytical model and numerical formulation from the field observations in the authors’ previous work. For this purpose, the modal analyses of the two finite element models are conducted to calculate the natural frequency and normalized mode shape of the individual modes of the bridge. The modal coupling assessment is also performed to obtain the generalized mass ratios among the structural components for each mode of the bridge.

The findings indicate that the coupled modes are attributed to the frequency loci veering and mode localization when the “pure” deck-tower frequency and the “pure” stay cable frequency approach one another, implying that the mode shapes of such coupled modes are simply different from those of the deck-tower system or stay cables alone. The distribution of the generalized mass ratios between the deck-tower system and stay cables are useful indices for quantitatively assessing the degree of coupling for each mode. For each identical group of stay cables in the MECS model, the local modes with similar natural frequencies and normalized mode shapes consist of the participation of one or more stay cables. These results are demonstrated to fully understand the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges.

It is important to investigate the deck-stay interaction with the appropriate initial shape of a cable-stayed bridge. This is because such initial shape not only reasonably provides the geometric configuration as well as the prestress distribution of the bridge under the weight of the deck-tower system and the pretension forces in the stay cables, but also definitely ensures the satisfaction of the relations for the equilibrium conditions, boundary conditions and architectural design requirements. However, few researchers have studied the deck-stay interaction considering the initial shape effect. The objective of this paper is to fully understand the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges, which is validated by a symmetrical structure. The modal coupling assessment is also performed for quantitatively assessing the degree of coupling for each mode of the bridge.

The purpose of the study is to investigate and reveal this relationship of various engineering demand parameters (EDPs) of this structural type and intensity measures (IMs) under intra-plate earthquakes.

The nonlinear finite element model used was calibrated first to the existing results of the shaking table test to verify the modeling technique.

This paper investigated the relationship between intensity measures and various engineering demand parameters of cable-stayed bridges using intra-plate earthquakes. The correlation analysis and Pearson coefficient are used to study the correlation between EDPs and IMs. The results showed that peak ground velocity (PGV)/peak ground acceleration, peak ground displacement and root-mean-square of displacement showed weak correlation with IMs. PGV, sustained maximum velocity, a peak value of spectral velocity, A95 parameter, Housner intensity and spectral acceleration at the fundamental period, the spectral velocity at the fundamental period and spectral displacement at the fundamental period were determined to be better predictors for various EDPs.

This paper investigated the correlation between the intensity measures of intra-plate earthquakes with the seismic responses of a typical long-span cable-stayed bridge in China. The nonlinear finite element model used was calibrated to the existing results of the shaking table test to verify the modeling technique. In total, 104 selected ground motions were applied to the calibrated model, and the responses of various components of the bridge were obtained. This study proposed PGV as the optimal IM.

The purpose of this paper is to develop a simplified optimization calculation method to assess cable force of self-anchored suspension bridge based on optimization theories.

A simplified analysis method construction using Matlab is developed, which is then compared with the optimization method that considers the main cable’s geometric nonlinearity with software ANSYS in an actual bridge calculation.

This contrast proves the weak coherence and the adjacently interaction theory unreasonable and its limitation.

This paper analyzes the calculation method to assess cable force of a self-anchored suspension bridge and its application effect.