超长预应力钢绞线张拉过程测试及温度效应下预应力变化分析  

Testing and Analysis of Prestress Change Under Temperature Effect in Tension Process of Super-long Prestressed Steel Strand

作　　者：李正军 何会新 林新元 王晗 高华睿 张峰 LI Zhengjun;HE Huixin;LIN Xinyuan;WANG Han;GAO Huarui;ZHANG Feng(CCCC Fourth Highway Engineering Co.,Ltd.,Beijing 100022,China;School of Qilu Transportation,Shandong University,Jinan,Shandong 250002,China)

机构地区：[1]中交第四公路工程局有限公司,北京100022 [2]山东大学齐鲁交通学院,山东济南250002

出　　处：《施工技术》2020年第11期64-67,共4页Construction Technology

摘　　要：依托云南省昭通市的单跨吊混凝土混板梁悬索桥,通过工作锚表面贴应变片的方法对超长钢绞线锚下有效预应力进行测试,基于分级张拉过程中有效预应力实测数据,分析超长预应力张拉过程中稳压时间的确定。并进行24h温度与有效预应力测试。研究结果表明,对于JTG/T F50-2011《公路桥涵施工技术规范》规定的持荷5min并不能指导超长预应力钢绞线张拉;温度效应对超长预应力钢绞线的影响明显,温差变化为11.7℃时预应力变化率为11.8%。Based on the single-span suspension bridge with concrete slabs in Zhaotong,this paper tests the effective prestress under the anchor of super-long prestressed steel strand by means of strain gauge attached to the anchor meter.Based on the measured data of effective prestress in the process of graded tensioning,this paper analyzes the determination of pressure stabilizing time in the process of super-long prestress tensioning.Temperature and effective prestress are measured for 24 hours.The results show that the load holding for 5 minutes stipulated in Technical Code for Highway Bridge and Culvert Construction(JTG/T F50—2011)can not guide the tensioning of super-long prestressed steel strand.The influence of the temperature effect on the super-long prestressed steel strand is obvious,the prestressed rate is 11.8%when the temperature difference is 11.7℃.

关 键 词：桥梁工程 悬索桥 超长预应力钢绞线 初始张拉力 持荷时间 温度效应 

分 类 号：U448.25[建筑科学—桥梁与隧道工程]