考虑双重非线性的大跨度钢桁梁拱桥稳定性能评估  

Stability Performance Evaluation of Long⁃span Steel Arch Bridge with Truss Girder Based on Double Nonlinearity

作　　者：刘郭周 傅中秋[2] 李荫晓 赵英爱 张辉 LIU Guozhou;FU Zhongqiu;LI Yinxiao;ZHAO Ying’ai;ZHANG Hui(STECOL Corporation,Tianjin 300384,China;College of Civil and Transportation Engineering,Hohai University,Nanjing,Jiangsu 210024,China;Power China Road Bridge Group Co.,Ltd.,Beijing 100048,China)

机构地区：[1]中国电建市政建设集团有限公司,天津300384 [2]河海大学土木与交通学院,江苏南京210024 [3]中电建路桥集团有限公司,北京100048

出　　处：《施工技术（中英文）》2024年第12期52-57,共6页Construction Technology

摘　　要：为评估钢桁梁拱桥稳定性能,优化结构构造,以岐江河大桥为背景,建立考虑几何与材料非线性的钢桁梁拱桥弹塑性计算模型,考察矢跨比f/L、宽跨比W/L、初始线形偏差、钢材屈服强度对钢桁梁拱桥稳定性影响,探究横撑构造与数目、横梁与横撑抗弯刚度对结构稳定性的优化效果。分析结果表明:f/L介于0.20~0.25时,钢桁梁拱桥稳定性相对优越;保持桥梁跨度不变而增加宽度能提高结构稳定性,当W/L由1/8增加至1/4时,稳定系数提高1倍;初始线形偏差明显影响结构稳定性,当初始横向变形量控制在l/3 000~l/1 000时稳定系数下降5%,而当变形量>l/1 000时稳定系数下降18%;钢材屈服强度对结构稳定性影响较小,250~350MPa 5种强度下的稳定系数相差<7%;现有横撑中,双米撑稳定性最好,其次为米撑、X撑、双K撑、K撑;相同用钢量下,采用米撑构造比K撑构造性能更好;增加横撑数目或增加横梁、横撑抗弯刚度可提高钢桁梁拱桥稳定性。In order to evaluate the stability behavior of a steel arch bridge with truss girder and optimize the structural configuration,Qijiang River Bridge was used as the background.The effects of geometric and material nonlinearity were considered,and elastic⁃plastic calculation models of the steel arch bridge with truss girder was established.The influence of the rise⁃to⁃span ratio(f/L),width⁃to⁃span ratio(W/L),initial crookedness,and yield strength of the steel on the stability of the steel arch bridge with truss girder was studied.Additionally,improvements in lateral bracing types,lateral bracing numbers,and bending rigidity of lateral bracing and floor beams on structural stability were explored.The results show that when f/L is between 0.20 and 0.25,the stability of the steel arch bridge with truss girder is relatively superior.Increasing W/L while keeping the bridge span unchanged can significantly improve the structural stability.Increasing W/L from 1/8 to 1/4 results in a 1⁃time increase in the stability coefficient.The initial crookedness can reduce the structural stability.When the initial crookedness is controlled at l/3000 to l/1000,the stability coefficient decreases by 5%.Furthermore,the stability coefficient decreases by up to 18%when the deformation exceeds l/1000.The yield strength of the steel has little effect on stability.The stability coefficient difference under five yield strengths(250MPa to 350MPa)is less than 7%.Among the current bracing types,the double⁃star⁃shaped bracing has the best stability,followed by star⁃shaped bracing,X⁃shaped bracing,double⁃K⁃shaped bracing,and K⁃shaped bracing.Under the same steel consumption,the star⁃shaped bracing is more reasonable than the K⁃shaped bracing. The stability of the steel arch bridge with truss girder can be enhanced by increasing the lateral bracing numbers or the bending rigidity of cross beams and lateral bracing.

关 键 词：桥梁工程 拱桥 钢桁梁 双重非线性 稳定性 数值模拟 

分 类 号：U448.22[建筑科学—桥梁与隧道工程]