The tension forces of Cables in Cable-stayed bridges during their construction and operation may differ from initial conditions, which could affect the amount and distribution of internal forces on other parts of the bridge. If some bridge elements are loaded to their yield limits, alternating plasticity and incremental collapse could occur under moving and repeated loading. This study investigated the effect of the initial tension force on the stiffness, strength, shakedown limit load, and alternating plasticity of Cable-stayed bridges, which has not been studied so far. Two case study bridge models with Cables having different initial forces were tested using nonlinear static analysis under gravitational force and nonlinear dynamic analysis under transient moving loads. The results showed that changes in the initial Cable forces did not change the initial stiffness, ultimate strength, shakedown limit, alternating plasticity, or bridge reliability. These results were theoretically validated using plastic analysis theorems. This paper presents a new construction method for Cable-stayed bridges based on the finding that adjusting the Cable tension to the design value is not necessary during construction and operation. This method eliminates the need for tension adjustment and ensures that the final geometric shape of the bridge matches the expected profile. The proposed method offers a simpler and more efficient approach to constructing Cable-stayed bridges without compromising the safety and durability of the structure.

Rail profile irregularities are one of the main vibration sources to vehicle and track. In this paper derailment of a wagon moving on Cable-stayed bridge due to rail irregularities is investigated. The four-axle wagon model is a three-dimensional, non-linear model of a train freight car with 38 DOF. Two parallel rails of the track are modeled as Euler-Bernoulli beams on elastic points as rail pads. The bridge deck is modeled as a plate supported by some Cables. Using this model; the effects of wagon specifications, lateral position of the rails and rail irregularities on wagon derailment have been studied.

A nonlinear dynamic analysis, including soil-structure interaction, is developed to estimate the seismic response characteristics and to predict the earthquake response of Cable-stayed bridge towers with spread foundation. An incremental iterative finite element technique is adopted for a more realistic dynamic analysis of nonlinear soil-foundation-superstructure interaction system under great-earthquake ground motion. Two different approaches to model soil foundation interaction are considered: nonlinear Winkler soil foundation model and linear lumped parameter soil model. The numerical results show that the simplified lumped-parameter-model analysis provides a good prediction for the peak response, but it overestimates the acceleration response and underestimates the uplift force at the anchor between superstructure and pier. The soil bearing stress beneath the footing base is dramatically increased due to footing base uplift. The predominant contribution to the vertical response at footing base resulted from the massive foundation rocking rather than from the vertical excitation.

Span lengths of newly constructed Cable-stayed railway bridges continue to show increases relative to those of older bridges. Accompanying such increases is the importance of ensuring that vibrations of long-span Cable-stayed bridges satisfy both safety and serviceability requirements, particularly for bridges that support train passages. In contrast to modern design of bridges that support roadway vehicles, current methods for analyzing Cable-stayed railway bridges do not yet typically account for coupling effects that may occur between Cables and the surrounding bridge structure during train passages. This paper presents a computational framework for the nonlinear dynamic analysis of railway bridges based on a coupled train– bridge analytical model and investigates the significance of accounting for Cable-related coupling effects. A case study is then carried out, where coupled dynamic responses of Cables, towers, and girders of an in-service railway bridge are computed and compared to those obtained using an uncoupled approach. These comparisons demonstrate the merits of accounting for coupling phenomena when computing dynamic characteristics of Cable-stayed railway bridges and highlight benefits of the coupled analysis approach in bridge design applications.

Progressive collapse is a continuous spread and magnification of localized failure in structures, caused by an accidental load, resulting in a cascade of failure affecting a large portion of the structure. Although alternate path method is the most widely used method to increase the structural robustness of bare frame structures against progressive collapse, it should be further developed for other structures, and especially Cable stayed bridges as they are highly sensitive to dynamic impact loading. This paper demonstrates modelling and analysis of a typical Cable stayed bridge through two important analytical procedures, i.e., nonlinear static and nonlinear dynamic. Furthermore, the response of the structural model is discussed for multiple types of Cable loss cases. Two different progressive collapse patterns are identified for nonlinear static and dynamic procedures as the dynamic unloading function is considered in the dynamic analysis procedure. The results also indicate a decrease in the possibility of failure progression of the Cable stayed model when the location of the failed Cables is closer to the pylon.