转速对桥梁水平转体结构受力及稳定性影响的模型试验研究

Model Test Study on the Influence of Rotating Speed on the Stress and Stability of Horizontal Rotating Structure of Bridge

研究转速对水平转体桥梁结构受力及稳定性影响可为桥梁转体施工提供控制依据。依据跨襄阳北编组站大桥新型转体系统,建立1∶10转体模型,分析了不同转速下主梁、转台及驱动承力撑脚的应力变化规律,并研究了主梁倾角、驱动牵引力随转速的变化特征。研究结果表明:转体系统加速启动阶段,主梁应力随转动加速度的变化很小,可忽略不计;以不同转速进行匀速转动时,主梁、转台、支腿应力变化率、驱动牵引力和主梁倾角变化幅度随转速的增大而增大,桥梁稳定性随转速的增大而降低;上部结构配重增大会降低转动稳定性,实桥转体时建议转速控制在0.02~0.04 rad/min。

The research on the influence of rotating speed on the stress and stability of horizontal swivel bridge structure can provide control basis for bridge swivel construction.According to the new swivel system of Xiangyang North Marshalling Station Bridge,a 1∶10 swivel model was established,the stress variation laws of the girder,turntable and driving-bearing leg at different speeds were analyzed,and the variation characteristics of the girder inclination and driving traction force with the speed were studied.The results show that in the acceleration start-up stage of the swivel system,the change of the girder stress with the swivel acceleration is very small and can be ignored.When rotating at a uniform speed,the change rate of girder stress,turntable stress and driving-bearing leg stress increase with the increase of swivel speed,and the stability of bridge decreases with the increase of swivel speed.The increase of superstructure counterweight will decrease the rotation stability.It is recommended to control the speed at 0.02~0.04 rad/min when the real bridge rotates.