大吨位小半径环向预应力钢束张拉伸长量综合分析法  

Comprehensive Analytical Method of Tensioning Elongation of Great Tonnage and Small Radius Annular Prestressing Tendons

作　　者：万利军[1] 单炜[1] 

机构地区：[1]东北林业大学土木工程学院,黑龙江哈尔滨150040

出　　处：《公路交通科技》2011年第6期97-102,121,共7页Journal of Highway and Transportation Research and Development

基　　金：黑龙江省交通厅重点科技项目(01230155)

摘　　要：为研究大吨位小半径环向预应力钢束的孔道摩阻系数及钢束伸长值理论计算方法,以哈尔滨四方台斜拉桥为研究对象,进行索塔锚固区节段足尺模型试验及张拉工艺试验。通过试验现象观测、数据分析及孔道局部解剖,系统地分析了影响张拉伸长量的主要因素。研究结果表明:基于最小二乘原理的多变量数据拟合技术为分束计算μ值提供了可靠依据;引入等效束型概念,避免了预应力束伸长量计算前后假定不一致的问题;综合考虑钢束内部的弹性伸长量、由束效应与小半径效应引起的附加伸长量、张拉工作段伸长量及锚具压缩引起的伸长量的计算方法,对大吨位小半径环向预应力钢束张拉伸长量超过现行规范规定的现象,能作出合理解释,对规范在直梁张拉基础上得出的伸长量计算方法是有益补充。In order to study the tube frictional resistance of great tonnage and small radius annular prestressing tendons and the theoretical calculation method of tendons elongation,the full-scale model test and tensioning craft experiment for the cable-pylon anchorage zone was made based on the Sifangtai cable-stayed bridge in Harbin.The principle influencing factors of tensioning elongation were analyzed systematically through test phenomenon observation,data analysis and partial dissection of tube.The research result manifests that（1） the multivariable data fitting technique based on method of least square provided reliable basis for calculating μ of each tendon;（2） the discord between the previous presumption of elongation of tendons and the latter one can be avoided by taking advantages of the conception of equivalent tendons;（3） the phenomena of tensioning elongation of great tonnage and small radius annular prestressing tendons exceeding current criterion can be explained reasonably by the calculation method which comprehensively considering elasticity elongation of internal tendons,addition elongation caused by tendons effect and small radius effect,tensioning active section elongation and elongation caused by anchorage compression.It can also be regarded as an useful supplement for setting rules for the calculation on the basis of straight girder tensioning.

关 键 词：桥梁工程 理论伸长值 试验研究 小半径预应力束 索塔锚固区 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]