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投稿时间：2018-03-12 修订日期：2018-11-21
投稿时间：2018-03-12 修订日期：2018-11-21
中文摘要: 研究了大跨斜拉桥用大吨位CFRP拉索的锚固问题和超长拉索带来的特殊安装问题。通过有限元分析方法建立了变刚度荷载传递材料（LTC）锚固系统和斜拉索安装系统的非线性模型。锚固性能方面，优化了荷载传递介质的弹性模量、长度、内锥角、受荷端厚度、界面摩擦系数，并进行了强度校核。拉索安装方面，研究了锚具修正角、拉索两端索力差值和拉索变形等关键参数，并对长度为1 085 m的钢拉索和CFRP拉索的安装参数进行了对比。结果表明：变刚度荷载传递材料减小了锚固区的应力集中。依据各部分材料性能要求，得到了拉力为15 000 kN CFRP拉索锚固系统的设计参数，包括钢套筒长度1 000 mm，直径424 mm，壁厚40 mm，内锥度为5°和采用45#高强度结构钢；荷载传递材料加载端半径40 mm，各区段弹性模量取值范围为1～2 GPa（LTC-1）、4～7 GPa（LTC-2）、15～25 GPa（LTC-3）、30～40 GPa（LTC-4）；各区段荷载传递材料选择为树脂与石英砂混合物（LTC-1和LTC-2）、聚合物砂浆或者高性能混凝土（LTC-3和LTC-4）。拉索安装方面，得到CFRP拉索的锚具修正角、拉索两端的索力差值、拉索变形。对于最长的拉索，主塔锚固点与主梁锚固点的锚固力差值，CFRP拉索是钢拉索的1/6；锚具修正角与拉索长度为正相关，并且CFRP拉索锚具修正角仅为钢拉索的1/4；与钢拉索相比，CFRP拉索的垂度小，锚具修正角减小1°，更利于拉索安装。
Abstract:The anchoring problem of large-tonnage CFRP cable for the long-span cable-stayed bridge and the special installation problems caused by long-cables were studied. The nonlinear model of the anchorage system with variable stiffness of load transfer component (LTC) and the installation system of stayed cable had been established by finite element simulation. The performance of the LTC was optimized, including the elastic modulus, the length, the internal taper and the thickness at loading end and the interfacial friction coefficient, and its strength was evaluated. For cable installation, the key parameters was studied, including the correction angle, the difference of cable force at two ends of the cables and the deformation of the cables, and the installation parameters of steel cable and CFRP cable with the length of 1 085 m was compared. The results show that the stress concentration in anchor zone is reduced by the variable stiffness of the LTC. Based on the material requirements of each part, the design parameters of anchorage system of CFRP cable with 15 000 kN are obtained. The steel sleeve needs a length of 1 000 mm, a diameter of 424 mm, a wall thickness of 40 mm and an internal taper of 5° by 45# high-strength structural steel; the radius of load transfer material at loading end is 40 mm, and the elastic modulus of each section ranges from 1 to 2 GPa (LTC-1), 4 to 7 GPa (LTC-2), 15 to 25 GPa (LTC-3), and 30 to 40 GPa (LTC-4). The selection of load transfer materials for each section is a mixture of resin and quartz sand (LTC-1 and LTC-2), polymer mortar or high performance concrete (LTC-3 and LTC-4). The installation correction angle, the difference of cable force in both ends of the cable and the deformation of the cable are obtained for the cable installation. The difference of CFRP and steel cable in anchoring force between the main tower and the main girder, CFRP cable of the longest is 1/6 of that of steel cable. The relationship between anchorage correction angle and the cable length is positively correlated, and the correction angle for CFRP cable is only 1/4 than that of steel cable. Compared with steel cable, the CFRP cables have smaller sag, and the correction angle is reduced by 1°, which benefits the cable installation.
文章编号：201800270 中图分类号：TU381 文献标志码：
基金项目:国家重点研发计划资助项目（2017YFC0703000）；国家自然科学基金资助项目（51878149；51678139）
作者简介:冯博(1986-),男,博士生.研究方向:大跨度斜拉桥设计评估及拉索锚固技术.E-mail:BoFengSEU@163.com
引用文本：
冯博,汪昕,吴智深.大吨位CFRP拉索的锚固性能及安装参数研究[J].工程科学与技术,2019,51(1):68-74.
FENG Bo,WANG Xin,WU Zhishen.Study on the Anchoring Performance and the Installation Parameters for the Large-tonnage CFRP Cable[J].Advanced Engineering Sciences,2019,51(1):68-74.
引用文本：
冯博,汪昕,吴智深.大吨位CFRP拉索的锚固性能及安装参数研究[J].工程科学与技术,2019,51(1):68-74.
FENG Bo,WANG Xin,WU Zhishen.Study on the Anchoring Performance and the Installation Parameters for the Large-tonnage CFRP Cable[J].Advanced Engineering Sciences,2019,51(1):68-74.