可滑动钢锚箱组合索塔锚固结构力学性能试验研究  

Experimental Research on Mechanical Property of Sliding Steel Anchor Boxes Used to Anchor Stay Cables in Pylons

作　　者：孙迎春 张育智[2] 谭珂 赵灿晖[2] 舒本安 SUN Yingchun;ZHANG Yuzhi;TAN Ke;ZHAO Canhui;SHU Benan(Foshan Jianying Development Co.,Ltd.,Foshan 528313,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Foshan Transportation Science and Technology Co.,Ltd.,Foshan 528314,China)

机构地区：[1]佛山市建盈发展有限公司,广东佛山528313 [2]西南交通大学土木工程学院,四川成都610031 [3]佛山市交通科技有限公司,广东佛山528314

出　　处：《桥梁建设》2024年第4期86-92,共7页Bridge Construction

基　　金：国家重点研发计划项目(2021YFB1600300)。

摘　　要：佛山富龙西江特大桥4~26号斜拉索塔上锚固采用可滑动钢锚箱组合索塔锚固结构,为掌握这种新型索塔锚固结构的力学性能,开展1∶2缩尺模型试验,对滑动副的工作性能、钢锚箱和混凝土塔柱应力状态、钢锚箱与混凝土塔柱间竖向相对滑移量、斜拉索索力传递路径及混凝土塔壁裂缝的发展规律进行研究。结果表明:镜面不锈钢与双组份石墨烯改性氟碳漆涂层组成的滑动副摩擦系数为0.055,适合作为可滑动钢锚箱的滑动副;钢锚箱侧拉板在斜拉索索力作用下处于拉、弯、剪复合受力状态,最大应力为150 MPa,应力水平较低,混凝土塔柱顺桥向最大拉应力仅为0.57 MPa,即使不设预应力也无开裂风险;钢锚箱与混凝土塔柱间的竖向相对滑移量很小,二者间连接可靠,能够很好地共同承受竖向索力;滑动端锁定前,竖向索力几乎全部由钢锚箱的固定端通过剪力连接件传递给混凝土塔柱,水平索力几乎全部由钢锚箱承担,滑动端锁定后,斜拉索索力增量由钢锚箱与混凝土塔柱共同承担;加载至2.5倍标准组合索力过程中,结构依次出现竖向裂缝和水平裂缝,所有裂缝宽度均较小,最大宽度仅0.2 mm。In the Fulong Xijiang River Bridge in Foshan,the stay cables No.4-No.26 are anchored in the pylons via a type of sliding steel anchor boxes.A 1∶2 scale model was prepared to test multiple issues related to the mechanical properties of the new type cable-pylon anchorage structure,including the working performance of sliding sets,stresses in steel anchor boxes and concrete pylon columns,the vertical relative sliding between steel anchor boxes and concrete pylons,force transfer paths of stay cables and propagation of cracks in concrete walls.The results show that the friction coefficient of the sliding set formed of stainless-steel concave and two-component graphene-modified fluorocarbon anticorrosive coating is 0.055,suitable for the sliding steel anchor box.Under the action of stay cable forces,the lateral tensile plate in the steel anchor box endures the interaction of tensile,bending and shear stresses,with the maximum stress reaching 150 MPa,relatively low.The maximum tensile stress in the concrete pylon columns along the bridge length is 0.57 MPa,indicating that there is no potential cracking risk even without prestress.The relative vertical sliding between the steel anchor box and concrete pylon columns is slight,proving that there exists a reliable connection between the two,and the two can carry vertical cable forces together.Before the locking of the sliding end,nearly all the vertical forces are transferred to the concrete pylon columns via the shear connectors at the fixed end of the steel anchor box,and roughly all the horizontal forces are carried by the steel anchor box.After the locking of the sliding end,the stay cable force increments are shared by the steel anchor box and concrete pylon column.When loaded to 2.5 times of the standard combination of stay cable forces,vertical and horizontal cracks gradually appeared in the structure,but the widths of all the cracks are small,with a maximum crack width of merely 0.2 mm.

关 键 词：斜拉桥 组合索塔锚固结构 滑动副 可滑动钢锚箱 混凝土塔柱 索力传递路径 裂缝 模型试验 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U443.38[交通运输工程—道路与铁道工程]