悬索管道桥双主缆式索夹抗滑移性能研究

Study on Anti-sliding Performance of Double Main Cable Clamp for Suspended Cable Pipeline Bridge

为解决超大荷载情况下双主缆体系悬索管道桥索夹的抗滑移问题,通过拉力试验机模拟吊索在主缆上的下滑力,根据索夹负荷-位移曲线以及索夹摩阻因数相互验证索夹抗滑移性能。结果表明:负荷-位移曲线可以显示索夹的位移情况,初步判定索夹是否产生滑移,但仍需通过分析锚固螺栓轴力来计算索夹摩阻因数,进一步将数据结果与规范要求进行对比;螺栓轴力监测数据中最大轴力(22.6 kN)约为最小轴力(14.3 kN)的1.58倍,主要原因在于双缆索夹体积较大,螺栓紧固力的均匀性相对较弱,而索夹内摩阻力主要受螺栓紧固力的影响。由于管道安装、试压等工况对主缆影响较大,建议双主缆式索夹在安装完成后,对索夹锚固螺栓进行复拧,以进一步确保索夹内应力的均匀性,提高索夹的抗滑移能力。

In order to solve the problem of anti-sliding of cable clamp in suspended cable pipeline bridge with double main cable system under super large load,the sliding force of the sling on the main cable is simulated on the tension test machine,and the anti-sliding performance of the clip is verified according to the load-displacement curve of the clip and the friction coefficient of the clip.The results show that the load-displacement curve can show the displacement of cable clip and can preliminarily determine whether the cable clip has slippage.However,it is still necessary to calculate the friction factor of the cable clip by analyzing the axial force of the anchor bolt and to further compare the data results with the requirements of the code.The maximum axial force(22.6 kN)is about 1.58 times of the minimum axial force(14.3 kN).The main reason is that the volume of double cable clamp is large and the uniformity of bolt fastening force is relatively weak,while the internal friction resistance of cable clip is mainly affected by bolt tightening force.In view of the great influence of pipeline installation and pressure test on the main cable,it is suggested that the cable clamping anchor bolt should be re-screwed after the installation of the double main cable clamp,so as to further ensure the uniformity of the stress in the cable clip and to improve the anti-skid ability of the cable clip.