轨道交通钢混结合连续梁设计及关键技术研究

Study on Design and Key Technology of Steel-concrete Composite Continuous Beam for Rail Transit

摘要:

钢混组合结构能充分发挥混凝土和钢结构的材料性能优势被越来越广泛应用。施工过程大节段钢梁吊装，对路口的交通影响较小等优点使得钢混结合梁在城市建设中占据重要地位。在轨道交通桥梁中，混凝土桥面板还能很好的与轨道结构相适应。本文结合长沙市轨道交通1号线北延一期工程高架区间跨开顺路口的（40+60+40）m钢混结合连续梁，分析钢混结合连续梁的结构受力特性。研究了采用不同措施如桥面板分段浇筑、正弯矩区压重、支点顶升落架、支点双结合、使用抗拔不抗剪连接件等对改善负弯矩区桥面板受力的优劣势。研究结果表明，钢混结合连续梁在城市轨道交通中的应用良好；采用支点顶升落架、支点双结合两个措施对改善桥面板受力效果最优。本文研究可供同类桥梁设计做参考。

Abstract:

The steel-concrete composite structure is more and more widely used because of its giving full play to the material performance advantages of concrete and steel structure. The advantages of steel large-segment beam hoisting in the construction process and a little impact on the traffic at the intersection make the steel-concrete composite beam occupy an important position in urban construction. In rail transit bridges, the concrete bridge decks can also be well adapted to the track structure. Combined with the (40+60+40) m steel-concrete composite continuous beam in the elevated section of Changsha Rail Transit Line 1 North Extension Phase I Project spanning the intersection of Kaishun Road, the structural stress properties of the steel-concrete composite continuous beams are analyzed. The advantages and disadvantages of different measures such as the segmental pouring of bridge deck slab, weighting in positive bending moment zone, fulcrum jacking and landing, double combination of fulcrum, and the use of anti-pulling and non-shearing connectors to improve the stress of bridge deck slab in negative bending moment zone are studied. The study results show that the steel-concrete composite continuous beam is well used in urban rail transit. Two measures of fulcrum jacking and landing, and double combination of fulcrum have the best effect on improving the stress of the bridge deck.