Most studies have analyzed the aerodynamic characteristics and wind-train(vehicle)-bridge coupled vibration response of trains or vehicles on bridges of a certain structural system,while few comparative studies have b...Most studies have analyzed the aerodynamic characteristics and wind-train(vehicle)-bridge coupled vibration response of trains or vehicles on bridges of a certain structural system,while few comparative studies have been carried out on the wind-train-bridge coupled vibration response on bridges of three different structural systems.This paper takes the main span 1120 m dual-purpose highway-railway bridge as the engineering background,and studies the three bridge types of(122+1120+90+92)m suspension bridge,(130+432+1120+432+130)m cable-stayed bridge and(92+210+1120+210+92)m cable-stayed-suspension collaborative system bridge.The trend of the maximum value of the train dynamic response to the wind-train-bridge coupling of the three structural system bridges as well as the speed thresholds are compared and analyzed,and conclusions are drawn:1)Under the same speed,the maximum value of train safety indexes in three types of bridges increases with the increase of wind speed.2)Under the same wind speed,the safety and smoothness indicators of trains in three types of bridges without wind barriers rank in the order of cable-stayed suspension collaborative system bridge>cable-stayed bridge>suspension bridge.3)At low wind speeds(≤15 m/s),a 3.0 m wind barrier has negligible effect on speed thresholds.The safety ranking of structural systems remains unchanged:cable-stayed-suspension collaborative system bridge>cable-stayed bridge>suspension bridge.4)At high wind speeds(≥20 m/s),the 3.0 m wind barrier can increase the train speed threshold for bridges within the same structural system.The safety ranking of the three bridge types(3.0 m 30%wind barrier)remains unchanged:cable-stayed suspension collaborative system bridge>cable-stayed bridge>suspension bridge.This study represents the first systematic comparative analysis of wind speed critical values and performance ratings across three distinct bridge structural systems.展开更多
In order to study the safety and the comfort of high-speed trains running on a single-tower cable-stayed bridge under spatial gust,a dynamic model of wind-train-bridge analysis model is built based on the autoregressi...In order to study the safety and the comfort of high-speed trains running on a single-tower cable-stayed bridge under spatial gust,a dynamic model of wind-train-bridge analysis model is built based on the autoregressive method,the multi-body dynamics method and the finite element method.On this basis,the influence of spatial gust model loading,the suspension parameters change,wind attack angle and speed on the train-bridge system are analyzed by combining the time/frequency domain analysis and statistical methods.The results show that the spatial gust environment is one of the most important factors affecting safety and comfort and can make the calculation result tend to be conservative and more conducive.The response changes caused by K_(py),K_(px)and K_(sx)changes are nearly linear,while Ksy shows nonlinear characteristics and the most sensitivity.Wind attack angle at 75°and 90°has the greatest influence on the vehicle-bridge system.For ride comfort index,when pre-set wind speed(α=75°)reaches 20 m/s,the vertical acceleration firstly exceeds the limit value;when wind speed(α=90°)reaches 21.5 m/s,the lateral acceleration firstly exceeds the limit value,and the ride comfort of the vehicle cannot be guaranteed.For running safety index,when pre-set wind speed(α=75°)reaches 24.6 m/s,the wheel unloading coefficient firstly exceeds the limit;when pre-set wind speed(α=90°)reaches 24.5 m/s,the derailment coefficient firstly exceeds the limit,and the running safety cannot be guaranteed.The results can provide a suitable reference for the safe and stable operation of trains on the bridge.展开更多
基金Project(52327810)supported by the National Natural Science Foundation of ChinaProject(51925808)supported by the National Natural Science Foundation for Distinguished Young Scholars of China+1 种基金Project(U1934209)supported by the Key Project of National Natural Science Foundation of ChinaProject(P2019G002)supported by the Science and Technology Research and Development Program of China National Railway Group Co.,Ltd。
文摘Most studies have analyzed the aerodynamic characteristics and wind-train(vehicle)-bridge coupled vibration response of trains or vehicles on bridges of a certain structural system,while few comparative studies have been carried out on the wind-train-bridge coupled vibration response on bridges of three different structural systems.This paper takes the main span 1120 m dual-purpose highway-railway bridge as the engineering background,and studies the three bridge types of(122+1120+90+92)m suspension bridge,(130+432+1120+432+130)m cable-stayed bridge and(92+210+1120+210+92)m cable-stayed-suspension collaborative system bridge.The trend of the maximum value of the train dynamic response to the wind-train-bridge coupling of the three structural system bridges as well as the speed thresholds are compared and analyzed,and conclusions are drawn:1)Under the same speed,the maximum value of train safety indexes in three types of bridges increases with the increase of wind speed.2)Under the same wind speed,the safety and smoothness indicators of trains in three types of bridges without wind barriers rank in the order of cable-stayed suspension collaborative system bridge>cable-stayed bridge>suspension bridge.3)At low wind speeds(≤15 m/s),a 3.0 m wind barrier has negligible effect on speed thresholds.The safety ranking of structural systems remains unchanged:cable-stayed-suspension collaborative system bridge>cable-stayed bridge>suspension bridge.4)At high wind speeds(≥20 m/s),the 3.0 m wind barrier can increase the train speed threshold for bridges within the same structural system.The safety ranking of the three bridge types(3.0 m 30%wind barrier)remains unchanged:cable-stayed suspension collaborative system bridge>cable-stayed bridge>suspension bridge.This study represents the first systematic comparative analysis of wind speed critical values and performance ratings across three distinct bridge structural systems.
基金Project(20ZR1460700)supported by the Natural Science Foundation of Shanghai,ChinaProject supported by Shanghai Collaborative Innovation Research Center for Multi-network&Multi-modal Rail Transit,China。
文摘In order to study the safety and the comfort of high-speed trains running on a single-tower cable-stayed bridge under spatial gust,a dynamic model of wind-train-bridge analysis model is built based on the autoregressive method,the multi-body dynamics method and the finite element method.On this basis,the influence of spatial gust model loading,the suspension parameters change,wind attack angle and speed on the train-bridge system are analyzed by combining the time/frequency domain analysis and statistical methods.The results show that the spatial gust environment is one of the most important factors affecting safety and comfort and can make the calculation result tend to be conservative and more conducive.The response changes caused by K_(py),K_(px)and K_(sx)changes are nearly linear,while Ksy shows nonlinear characteristics and the most sensitivity.Wind attack angle at 75°and 90°has the greatest influence on the vehicle-bridge system.For ride comfort index,when pre-set wind speed(α=75°)reaches 20 m/s,the vertical acceleration firstly exceeds the limit value;when wind speed(α=90°)reaches 21.5 m/s,the lateral acceleration firstly exceeds the limit value,and the ride comfort of the vehicle cannot be guaranteed.For running safety index,when pre-set wind speed(α=75°)reaches 24.6 m/s,the wheel unloading coefficient firstly exceeds the limit;when pre-set wind speed(α=90°)reaches 24.5 m/s,the derailment coefficient firstly exceeds the limit,and the running safety cannot be guaranteed.The results can provide a suitable reference for the safe and stable operation of trains on the bridge.
