复杂温度场对大跨悬索桥线-桥受力变形特性影响分析

Impact of Complex Temperature Fields on the Track-Bridge Stress Deformation Characteristics of Long-Span Suspension Bridges

为研究复杂温度场对大跨悬索桥线-桥受力变形特性的影响,基于线-桥相互作用理论,建立无缝线路-有砟轨道-悬索桥空间耦合模型,分析复杂温度场作用下大跨悬索桥线-桥受力变形特征,通过对桥上线路变形进行信号分解,获取线路不平顺特征波长,并采用60 m和10 m中点弦测法,分别对桥上线路高低和轨向平顺性进行评估。研究结果表明:在复杂温度场作用下,桥上无缝线路不存在固定区;复杂温度场作用下,线-桥变形更为复杂,整体温升工况下线路线形更为圆顺,钢轨横向变形大幅减小,横向位移需要关注局部温梯的影响;温度场作用下,线-桥垂向基本完全映射,横向线与桥的跟随性良好;线路存在特征波长,高低和轨向不平顺的特征波长主要为2.8、14.0、28.0 m,分别对应桥梁的横梁间距、节间间距和标准节间长度;复杂温度场作用下,大跨悬索桥上轨道高低与轨向平顺性状态良好。研究成果可为大跨悬索桥上线路的设计、重点区域检测监测及养护维修提供参考。

To study the impact of complex temperature fields on the track-bridge stress deformation characteristics of long-span suspension bridges,this paper establishes a spatial coupling model of CWR-ballasted track-suspension bridge based on the theory of track-bridge interaction,and analyzes the track-bridge stress deformation characteristics of the long-span suspension bridge under the influence of complex temperature field.The characteristic wavelength of track irregularity is obtained by performing signal decomposition of line deformation on the bridge.Additionally,the 60m and 10m midpoint chord measurement method is employed to assess the longitudinal level and alignment regularity.The research results indicate that under the influence of complex temperature fields,there are no fixed zones for CWR on the bridge.The deformations of the track-bridge become more complex under these conditions.In the case of overall temperature rise,the track alignment is smoother,while the lateral deformation of the rails significantly decreases.Attention should be paid to the effects of local temperature gradients on lateral displacement.Under the influence of the temperature field,the vertical responses of the track-bridge are nearly completely mapped,and the lateral alignment shows good adherence to the bridge structure.The line exhibits characteristic wavelengths,with the wavelengths for longitudinal level and alignment irregularity primarily being 2.8 m,14.0 m,and 28.0 m,corresponding to the spacing of the bridge’s transverse beams,the spacing between panels,and the standard panel length,respectively.Under complex temperature field,the longitudinal level and alignment regularity on the long-span suspension bridge remain in good condition.The research findings can provide references for line design on long-span suspension bridges,as well as for monitoring and maintenance of key areas.