武汉青山长江公路大桥1860 MPa级斜拉索锚具设计研究  

Study of Anchorage Design for 1860 MPa-Grade Stay Cables of Qingshan Changjiang River Highway Bridge in Wuhan

作　　者：吴琼 强强 周祝兵 王志刚 周能作 WU Qiong;QIANG Qiang;ZHOU Zhu-bing;WANG Zhi-gang;ZHOU Neng-zuo(Jiangsu Fasten Steel Cable Co.,Ltd.,Jiangyin 214445,China)

机构地区：[1]江苏法尔胜缆索有限公司,江苏江阴214445

出　　处：《桥梁建设》2020年第S01期106-111,共6页Bridge Construction

摘　　要：武汉青山长江公路大桥主桥为主跨938m的钢箱及钢箱结合梁斜拉桥,斜拉索采用抗拉强度1 860MPa、Φ7mm低松弛锌铝合金镀层钢丝拉索。为确保高强度、大规格斜拉索的锚固性能,从力学性能、淬透性、可加工性和经济性等方面,对40Cr、42CrMo、40CrNiMo 3种锚具材料进行比选;在选定锚具材料的基础上,通过分析锚具和缆索受力特性,确定锚具结构尺寸参数;制作试验索,开展静载试验和疲劳试验,分析锚具的静、动力性能。结果表明:42CrMo钢力学性能、淬透性、可加工性及经济性等均较优,确定为锚具最佳材料;锚具结构尺寸参数取值合理,可保证锚具力学性能满足要求;试验索在斜拉索98%公称破断载荷下,钢丝没有拔出,锚杯与锚圈无损伤,在200万次循环轴向加载下,钢丝没有断丝,外观完好,验证了锚具结构设计合理、可靠。The main bridge of Qingshan Changjiang River Highway Bridge in Wuhan is a cablestayed bridge with a main span of 938 m.The superstructure consists of steel box girders and steel box-concrete composite girders.The stay cables are composed ofΦ7 mm low-relaxation Zn-Al alloy coated steel wires,each with a tensile strength of 1 860 MPa.To ensure the anchoring performance of the high-strength and large-size stay cables,three types of materials,including 40 Cr,42 CrMo and 40 CrNiMo were compared,from aspects of mechanical property,hardenability,machinability and economy.Once the materials for the anchorage were determined,the load bearing behaviors of the anchorages and stay cables were analyzed to work out the structural dimension parameters of the anchorages.Testing cables were prepared for the static and fatigue tests to analyze the static and dynamic property of the anchorages.The results show that the 42 CrMo is regarded as the optimal material for anchorages,according to the comparison of three types of materials from aspects of mechanical property,hardenability,machinability and economy.The parameters of the anchorages are rational,which assures that the mechanical property of the anchorages can meet the requirements.No steel wire of the testing cables was dragged out of the anchorage and no damage was observed in anchor socket and anchor ring,under the action of 98%of nominal breaking load of the stay cable.Furthermore,no steel wire was broken under 2 million numerical cycles of axial loading,and the appearance of the stay cable was intact,which all met the code and design requirements.The materials used and the dimension designed for the anchorages are rational and reliable.

关 键 词：斜拉桥 斜拉索 锚具 材料比选 结构参数 静载试验 疲劳试验 结构设计 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U442.5[交通运输工程—道路与铁道工程]