摘要
拱圈外包混凝土的分环多工作面浇筑在工程上取得了成功,但该施工方法对大跨径400m以上拱桥仍需进一步研究来保证施工过程拱肋的受力与变形更加合理。以云桂铁路南盘江特大桥为例,建立该桥的有限元模型,在确定分环与分段数目的前提下,模拟不同的纵向浇筑顺序,系统分析外包混凝土多工作面浇筑过程中,不同浇筑顺序对拱圈结构的瞬时应力、永存应力、变形及稳定性的影响,得出最优浇筑顺序,为同类型拱桥的施工提出参考和依据。研究结果表明,浇筑顺序的改变可以优化浇筑过程中拱圈结构的瞬时应力与永存应力,最优浇筑顺序使下弦钢管最大环末永存应力降幅达7.8%,骨架受力更为合理,提高骨架应力的安全储备。
The casting of the arched outer-covered concrete with the sub-ring multi-face has been successful in project application,however,the construction method needs to be further studied for the arch bridge with the span length of 400 mor more to ensure that the force and deformation of the arch rib during the construction process more reasonable.Taking the Nanpanjiang Bridge of Yunnan-Guilin Railway as an example,the finite element model of the bridge is established.Under the premise of determining the number of sub-rings and segments,different longitudinal pouring sequences are simulated,and the outer-covered concrete in multiple work face pouring is systematically analyzed.During the pouring process,the influence of different pouring sequence on the instantaneous stress,permanent stress deformation and stability of the arch ring structure leads to the optimal pouring sequence,which provides reference and basis for the construction of the same type of arch bridge.The results show that the change of the pouring sequence can optimize the instantaneous stress and permanent stress of the arch ring structure during the casting process.The maximum permanent stress of the lower-chord steel pipe is reduced by 7.8%in the optimal pouring sequence,and the skeleton force is more reasonable,which improves the safety reserve of the skeleton stress.
作者
童加明
邓年春
林春姣
郭晓
TONG Jia-ming;DENG Nian-chun;LIN Chun-jiao;GUO Xiao(College of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China;Key Laboratory of Disaster Prevention and Engineering Structure Safety of Guangxi,Nanning 530004,China)
出处
《公路》
北大核心
2020年第7期92-97,共6页
Highway
基金
国家自然科学基金项目,项目编号51868006
广西高等学校高水平创新团队及卓越学者计划项目,项目编号桂教人〔2018〕35号
四川省科技计划项目,项目编号18ZDYF0942。
关键词
大跨劲性骨架拱桥
多工作面
均衡浇筑
外包混凝土
浇筑顺序
研究
long-span rigid skeleton arch bridge
multiple work face
balanced pouring
outer-covered concrete
pouring sequence
study
