工况参数对悬索桥主缆索股与鞍座动态接触与微滑移行为的影响研究

Study on the Influence of Working Condition Parameters on the Dynamic Contact and Microslip Behavior between Main Cable Strand and Saddle of Suspension Bridge

悬索桥主缆索股与鞍座间的动态接触与微滑移行为严重影响桥梁的服役安全性,而工况参数(交变载荷幅值、交变载荷频率、预紧力、摩擦因数等)对主缆索股与鞍座间动态接触与微滑移行为影响显著。因此,运用有限元软件ABAQUS和试验平台开展了主缆索股与鞍座间的接触分析和动态接触与微滑移试验,探究了不同工况参数下主缆索股与鞍座间的动态接触与微滑移特征(接触应力、接触压力、接触状态、微滑移幅值、摩擦因数等)。结果表明随着交变载荷幅值的增大,索股与鞍座间的接触状态呈黏着-部分滑动-完全滑动的变化趋势,微滑移幅值逐渐增大;随着交变载荷频率的增大,接触状态趋于向完全滑动状态转变,微滑移幅值逐渐增大;随着预紧力、摩擦因数的增大,接触状态趋于向黏着状态转变,微滑移幅值逐渐减小;鞍座固定端与加载端的接触压力在不同条件参数的影响下呈不同的变化趋势。基于仿真和试验结果的各条件参数对微滑移幅值影响程度排序分别为:交变载荷幅值>预紧力>摩擦因数和交变载荷幅值>预紧力>交变载荷频率。

The dynamic contact and microslip behavior between main cable strand and saddle of suspension bridge seriously affects the service safety of the bridge,and the working condition parameters(alternating load amplitude,alternating load frequency,preload force,friction coefficient,etc.)have a significant impact on the dynamic contact and microslip behavior between main cable strand and saddle.Therefore,the contact analysis and dynamic contact and microslip experiments between main cable strand and saddle are carried out by using finite element software ABAQUS and test apparatus,and the dynamic contact and microslip characteristic(contact stress,contact pressure,contact state,microslip amplitude,friction coefficient,etc.)between main cable strand and saddle under different conditions are explored.The results show that with the increase of the amplitude of alternating load,the contact state between cable strand and saddle shows a trend of adhesion-partial slip-complete slip,and the microslip amplitude increases gradually.With the increase of alternating load frequency,the contact state tends to change to the complete slip state,and the microslip amplitude increases gradually.With the increase of preload force and friction coefficient,the contact state tends to change to the adhesive state,and the microslip amplitude decreases gradually.Under the influence of different conditions,the contact pressure between the fixed end and the loading end of saddle shows different trends.Based on the simulation and experimental results,the order of the influence degree of each condition parameter on the microslip amplitude is:alternating load amplitude>preload force>friction coefficient and alternating load amplitude>preload force>alternating load frequency.