大跨径非对称悬浇连续梁设计实践

Design Practice of Long Span Asymmetrical Suspended Continuous Beam

常规连续梁结构采用对称设计,且边中跨比例宜取合理范围,当桥跨布置受地形或其他因素限制时,采用非对称设计是一种无奈的解决方法。大跨径非对称连续梁存在结构受力不合理、配束难度大、小边跨端支座易脱空、施工控制要求高等特点。本文以跨南水北调干渠大桥,主桥采用(52.5+130+75)m非对称变截面悬浇连续梁为例,通过建立模型计算分析,研究最不利受力状态,通过采取有效设计手段及施工措施,解决此类桥型存在的问题,可为类似桥梁的设计提供参考。

The conventional continuous beam structure adopts symmetrical design,and the ratio of side to middle span is reasonable.When the bridge span arrangement is limited by terrain or other factors,the asymmetric design is an effective solution.The large span asymmetric continuous beam has the characteristics of unreasonable structural stress,difficulty in bundling,easy to empty the small side span end support,and high construction control requirements.In this paper,the main bridge across the South-to-North Water Diversion canal adopts(52.5+130+75)m asymmetric variable section suspension continuous beam as an example,through the establishment of model calculation and analysis,the most unfavorable stress state is studied,and the existing problems of this type of bridge are solved by adopting effective design methods and construction measures,which can provide reference for the design of similar Bridges.