摘要
结合理论计算和实桥分析,对影响大跨径预应力混凝土连续箱梁合理应力状态的参数进行分析,以控制投入运营后结构的长期下挠变形.首先根据大跨径连续箱梁结构特点,采用按龄期调整的有效模量法并考虑其他4个影响徐变和收缩效应计算的因素提出了长期效用计算合理方法;然后以悬臂浇筑施工1座大型预应力混凝土连续箱梁桥为工程背景,采用分离式断面模型分析了结构设计参数(支点梁高、跨中梁高、支点截面底板厚度、腹板厚度等)与长期挠度的相关性,并以"零弯矩理论"为依据、考虑悬臂拼装4个阶段进行了预应力设计;通过对墩顶截面应力梯度的分析,明确了合理成桥应力状态设计方案.
Combined with theoretical calculation and a real bridge analysis, the parameters that affect the rational stress status of the long-span prestressed concrete continuous girder are analyzed in order to control the long-team deflection of the structure. Firstly, according to the structural characteristics of the long-span continuous girder, a reasonable method of long-term utility calculation is put forward by adopting the effective modulus method adjusted by the age and by considering four other factors that affect the calculation of the creep and shrinkage effects. Second, drawing on a large prestressed concrete continuous girder bridge being built with cantilever casting as the engineering background, the correlation of structural design parameters, such as the height of the pivot beam, the thickness of the mid-span beam, the bottom plate thickness of the box beam and the thickness of the web plate, is analyzed. Based on the zero bending moment theory and the four stages of cantilever assembly, the prestressing design is carried out. Through analyzing the stress gradient of pier top section, the design plan of reasonable bridge stress state is determined.
作者
郭明华
侯海涛
刘奎太
王建民
王帅
GUO Ming-hua;HOU Hai-tao;LIU Kui-tai;WANG Jian-min;WANG Shuai(Xiamen Highway Bureau,Xiamen 361007,China;School of Civil Engineering,Tsinghua University,Beijing 100084,China;Beijing Zhongjiao Hualian Technology Development Co.,Ltd.,Beijing 100101,China)
出处
《青岛理工大学学报》
CAS
2019年第2期31-37,87,共8页
Journal of Qingdao University of Technology
基金
福建省交通运输科技发展资助项目(201607)
关键词
大跨径梁桥
合理成桥应力状态
预应力
长期下挠
时变效应
long span girder bridge
rational bridge stress status
prestressing
long-term deflection
time-dependent effect
