摘要
以2座悬臂施工的预应力混凝土连续梁桥(跨径组合:75m+125m+75m;65m+100m+65m)为背景,对其成桥十年以来的长期挠度和裂缝的发展特点进行了研究。首先对其成桥后历年的实测挠度进行了阐述,发现桥梁跨中下挠的发展趋势呈现出"快速—缓和—加速"的特征。对裂缝的发展特点进行了分析,发现顶板及底板纵向裂缝普遍存在且分布密集,支点附近腹板斜裂缝相对出现较早。然后对桥梁各种主要类型的裂缝进行了分级和量化,并对挠度和裂缝进行了相关性分析。发现部分裂缝出现后,即使相对较为稳定,桥梁挠度也会继续增大。最后对持续下挠的原因进行了讨论,并给出了若干计算建议。
According to annual measured deflections and cracks of 2 three-span concrete box girder bridges constructed by free cantilevering method ten years ago, the characteristics of long-term deflections and crack propagation are analyzed. Firstly, the deflection growth of the bridges in the past ten years is summarized. It can be seen the growth of mid-span deflection is in the form of ＂fast- ease- speed up＂. Then the characteristics of crack propagation are described. It is found the distribution of longitudinal cracks on the top and bottom plates is widespread and compact, and the diagonal cracking of web near the supporting points occurs relatively earlier. After that, major types of cracks are classified and quantified, and correlation analysis of measured deflection and cracks is carried out. It is found the deflection will continue to increase although some cracks remain relatively stable. Finally, the causes leading to the sustained deflection are discussed, and some suggestions on the calculation of long-term deflection are given.
出处
《工程力学》
EI
CSCD
北大核心
2008年第A01期116-119,共4页
Engineering Mechanics
关键词
桥梁
长期挠度
实测挠度分析
裂缝
相关性
大跨度
bridge
long-term deflection
measured deflection analysis
crack
correlation
long-span
