基于无应力状态控制法的K式钢桁梁桥起拱研究  

Arching of K-Type Steel Truss Bridge Based on Unstressed State Control Method

作　　者：田仲初 邢锴 蔡岳 谭建平 许斌林 朱林 TIAN Zhongchu;XING Kai;CAI Yue;TAN Jianping;XU Binlin;ZHU Lin(School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,Hunan,China;School of Civil Engineering,Fujian University of Technology,Fuzhou 350118,Fujian,China;General Contracting Branch of China Communications Construction Co.,Ltd.,Beijing 100000,China)

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114 [2]福建理工大学土木工程学院,福建福州350118 [3]中国交通建设股份有限公司总承包经营分公司,北京100000

出　　处：《重庆交通大学学报（自然科学版）》2024年第10期1-6,18,共7页Journal of Chongqing Jiaotong University(Natural Science)

基　　金：国家自然科学基金项目(52078058);湖南省自然科学基金项目(2022JJ50323)。

摘　　要：目前工程上对于钢桁梁桥起拱问题的研究主要针对N式桁架节间,但K式钢桁梁桥节间的预拱度设置尚未有统一的计算方法。为解决K式节间的起拱问题,基于分阶段成形结构力学平衡方程,将节间的相对预拱度作为输入,推导得出各杆件伸缩量的数学表达式;针对下承式钢桁梁桥预拱度设置特点,进一步得出同时伸缩下斜腹杆与竖腹杆、同时伸缩下斜腹杆与上弦杆、同时伸缩上弦杆与上下斜腹杆共3种情况下的杆件伸缩公式,并借助实桥数据计算和几何试算进行验证。研究结果表明:该方法实用可行,充分验证了钢桁梁K式节间的无应力状态起拱为纯几何起拱,起拱过程不会产生附加内力和起拱支座反力。At present,the research on the arching problem of steel truss bridges in engineering mainly focuses on the N-type truss sections,but there is no unified calculation method for the pre-camber setting of K-type steel truss bridge sections.In order to solve the problem of arching in K-type sections,the mathematical expression for the expansion and contraction of each member was derived,which was based on the mechanical equilibrium equation of a structure formed in stages and took the relative pre-camber of the sections as an input.Aiming at the characteristics of the pre-camber setting of the through type steel truss girder bridges,the formulas for the expansion and contraction of the members were further obtained for three cases:simultaneous expansion and contraction of the lower diagonal web members and vertical web members,simultaneous expansion and contraction of the lower diagonal web members and upper chord members,and simultaneous expansion and contraction of the upper chord members and upper and lower diagonal web members.With the help of real bridge data calculation and geometric trial calculation,the proposed method was verified.The research results show that the proposed method is practical and feasible,which fully verifies that the unstressed arching of K-type steel truss bridge sections is an absolutely geometrical arching,and the arching process will not generate additional internal forces or reaction forces from the arching support.

关 键 词：梁桥工程 钢桁梁桥 K式桁架 预拱度曲线 无应力状态起拱法 

分 类 号：U448.36[建筑科学—桥梁与隧道工程]