Fatigue Life Assessment of Intercity Track Viaduct Based on Vehicle–Bridge Coupled System

Abstract

: During the long-term operation of an urban railway viaduct, it is subjected to multiple cyclic loads caused by the movement of a vehicle. As a result, the fatigue life of the bridge should be fully considered during the design process. Furthermore, the bridge structure will be subject to environmental corrosion for an extended period of time, resulting in concrete carbonization and reinforcement corrosion, which aggravates the bridge structure’s fatigue damage. To compensate for the disadvantage of the traditional static analysis method’s inability to consider vehicle speed, a vehicle–bridge system coupled model is established, material corrosion is considered, railway bridge damage under vehicle load is analyzed, and the service life of common 30 m and 25 m span bridges is calculated. The results show that ignoring corrosion will understate the bridge damage, and vehicle speed has a significant impact on bridge fatigue life. Finally, the recommended operating speeds for 30 m span and 25 m span bridges are provided.

Corrosion-Fatigue Life Prediction of the U-Shaped Beam in Urban Rail Transit under a Chloride Attack Environment

“…The reinforcement in the beam will produce variable amplitude stress cycles under the train load [ 40 ]. The rain flow counting method is used to obtain different stress ranges under variable amplitude stress cycle Δ σ i and its corresponding number of cycles n i .…”

Dynamic Response Study of Overhead Contact System Portal Structure Based on Vehicle–Track–Bridge Coupled Vibration

“…An analytical method for a coupled system of train-track-bridge-foundation based on lumped parameter models was proposed, and the coupling of subsystems was achieved using a modified component mode synthesis method [12]. Based on the established finite element simulation model of bridges, the deformation of the track caused by bridge deformation was added as an excitation to the coupled system, and the influence of additional bridge deformation on the dynamic response characteristics of the vehicle-track-bridge coupled system was analyzed [13]. The fatigue characteristics of railway bridges with different spans (25 m and 30 m) under train loads were analyzed, and recommended operating speeds corresponding to the spans were provided.…”

Evaluation of the Dynamic Amplification Factors of a Monorail Tourism Transit System Based on Probability Statistics

“…Coefficients were used to calculate and evaluate the remaining life of the bridge based on the minimum vibration impact coefficient [7]. Cui et al developed a coupled vehicle-bridge-system model that considered material corrosion, analysed the damage of rail road bridges under vehicle loading, and provided the recommended operating speeds for bridges with a span of 30 m and a span of 25 m. The model was used to calculate the vibration dynamic amplification factors of each part of large-span bridges more accurately [8]. Jiang et al used a Nielsen system lifting basket arch bridge on the Ji qing high-speed railway line as the research object and analysed the influence of vehicle speed and track irregularity level on random vibration characteristics such as the mean value of dynamic stress, standard deviation, and probability density results of the boom based on the probability density evolution method.…”