大跨度悬索桥长索夹抗滑承载能力研究

Study on Anti-sliding Bearing Capacity of Long Cable Clamp of Long-span Suspension Bridge

通过建立索夹主缆系统接触摩擦精细化模型,分别研究在不同的索夹壁厚、索夹紧固螺栓间距以及接触摩擦系数的条件下,紧固作用下的主缆表面径向应力和切向应力分布情况,评估主缆因不同紧固条件对长索夹抗滑承载能力的影响。结果表明主缆表面应力沿环向分布很不均匀,靠近索夹开口位置附近主缆表面接触应力明显大于索夹靠近主缆天顶线的接触应力;索夹壁厚主要对索夹开口处以及索夹变截面处的主缆表面应力产生影响,索夹壁厚越大抗滑安全系数越小;接触面摩擦系数越大,索夹开口位置附近切向应力越大,而接触面径向应力整体越小,同时索夹轴向最大摩擦阻力也越大;索夹间距只影响主缆整体的应力大小,随索夹间距增大,索夹抗滑摩阻力也越大,增大螺栓间距有利于提高索夹的抗滑承载能力。

By establishing the refined contact friction model of the cable clamp main cable system,the distribution of the radial stress and tangential stress on the main cable surface under the fastening action under the fastening conditions of different cable clamp wall thickness,cable clamp fastening bolt spacing and contact friction coefficient was studied respectively,and the impact of the main cable under different fastening conditions on the sliding resistance of the long cable clamp was evaluated.The results showed that the surface stress of the main cable is distributed unevenly along the circumference.The contact stress on the surface of the main cable near the opening of the cable clamp is significantly greater than that near the zenith line of the main cable.The wall thickness of the cable clamp mainly affects the surface stress of the main cable at the opening of the cable clamp and the variable cross-section of the cable clamp.The greater the wall thickness of the cable clamp,the smaller the anti sliding safety factor;The larger the friction coefficient of the contact surface is,the greater the tangential stress near the cable clamp opening position is,and the smaller the overall radial stress of the contact surface is,and the greater the axial maximum friction resistance of the cable clamp is;The cable clamp spacing only affects the overall stress of the main cable.The increase of the cable clamp spacing would increase the anti sliding friction resistance of the cable clamp,and the increase of the bolt spacing will help to improve the anti sliding bearing capacity of the cable clamp.