道庆洲大桥标准段钢桁结合梁关键技术研究

Research on Key Technology of Steel Truss Composite Beam in Standard Section of Daoqingzhou Bridge

福州市道庆洲过江通道工程为“公路+轨道交通”合建通道,位于闽江和乌龙江交叉口,本桥在设计过程中存在诸多限制因素和设计难题。为最大程度降低大桥对湿地的不利影响,减少地铁伸缩轨道调节器数量,标准段采用“7×84m”的连续钢桁结合梁;地铁桥面采用无砟轨道结构,减轻了轨道荷载;公路面采用“密横梁+混凝土板”组合结构,解决钢桥面铺装的难题;本桥不设置横向联结系,降低桁高,节约工程造价;地铁桥面设置“纵横梁+正交异性板整体钢桥面”以提高结构刚度。通过对本桥进行计算分析,本桥主桁应力、混凝土板裂缝、结构刚度均满足规范要求。

Fuzhou Daoqingzhou Bridge Project is a joint channel of “highway+rail”, located at the intersection of Minjiang River and Wulong River. There are many restrictive factors and design problems in the design process of this bridge. In order to minimize the adverse impact of the bridge on the wetland and reduce the number of metro telescopic track regulators, the standard section adopts “7×84 m” continuous steel truss composite beam. In order to reduce the track load, the subway bridge deck adopts ballastless track structure. To solve the problem of steel deck pavement, the highway surface uses the composite structure of “dense beam+concrete slab”. To reduce truss height and save project cost, the bridge is not provided with transverse connection system. “longitudinal and transverse beam+orthotropic plate integral steel deck” subway bridge deck is employed to improve the structural stiffness. The analysis of the bridge shows that the main truss stress, concrete slab crack and structural stiffness of the bridge meet the requirements.