列车作用下大跨度铁路悬索桥梁端纵向运动计算方法研究OA

The service performance of girder-end restraint devices in suspension bridges is influenced by the longitudinal movement of the stiffening girder as a key parameter.Accurately predicting the girder-end longitu-dinal displacement during train passage is crucial for optimizing the design,monitoring,and maintenance of these restraint devices.The Wufengshan Yangtze River Bridge was chosen as a case study.The calculation ac-curacy of the static method was evaluated through static load tests.A calculation method for train-induced lon-gitudinal movement at girder-ends was proposed,with comprehensive consideration of the longitudinal nonlin-ear resistance acting on the stiffening girder.The reliability of the method was verified using measured results.The longitudinal movement characteristics of girder-end and the variation laws of short hanger bending stress in the railway suspension bridge were investigated.Results demonstrate that the proposed method accurately predicts girder-end movement under train loads,showing strong agreement with field measurements.The girder-end displacement under train loads is limited to less than 1 mm by the longitudinal nonlinear resistance.Longitudinal relative displacement between the cable and girder at short hangers significantly increases the re-sults of static calculation.Its bending stress increases by 76.7%,and the central buckle stress amplitude in-creases by 3.6 times to 143.4 MPa.Bearing friction and girder-rail longitudinal interaction notably influences the longitudinal movement of the stiffened girder.The girder-end displacement values are exaggerated by the static calculation,and the stress levels of critical connecting components are underestimated.These findings provide useful references for clarifying the mechanism of train-induced longitudinal movement at girder-ends and for optimizing the design of restraint devices.