建筑高度限制条件下特大桥结构方案比选-20141008课稿.doc

建筑高度限制条件下特大桥结构方案比选 高燕梅、周志祥 (重庆交通大学，重庆，400074） 摘要：榕江特大桥位于广东省潮惠高速公路榕江河段，其建筑高度收到双重限制：桥下Ⅲ级航道，主跨跨度不小于380m；同时桥梁高度受机场控高要求的限制，潮州侧主墩桥梁控高96.56m，惠州侧主墩桥梁控高109m。因此考虑三种桥型方案：方案一为作者提出的下承式预应力钢桁－砼组合连续刚构桥方案，方案二为自锚悬索桥方案，方案三为钢-混凝土混合箱梁矮塔斜拉桥方案。本文着重阐述了方案一的结构设计理念，讨论了其结构总体布置和关键构造细节，并进行了施工和使用阶段的力学性能分析，论证了下承式预应力钢桁－砼组合连续刚构桥方案在特定条件下的可行性和合理性。 关键词：通航净空限制，桥梁高度限制，下承式预应力钢桁－砼组合连续刚构桥，设计理念，构造特点， 中图分类号：U443.38 文献标志码：A Scheme Comparison of Super-Large Span Bridge under the Condition of Limited Building Height Yanmei Gao, Zhixiang zhou (Chongqing Jiaotong University，Chongqing 400074，China, Chongqing, 400074, China lg2346@163.com zhixiangzhou@) Abstract: Rongjiang super-large bridge is a part of the highway from Chaozhou to Huizhou in Guangdong province. To ensure the normal navigation under the bridge and meet the requirements of Airfield Height Control, both the span and the height of the bridge are limited, thus the main span should not be less than 380m while the bridge heights of the pier on the Chaozhou and the other side should respectively not be more than 96.65m and 109m .Due to the double restrictions of span and bridge height, three schemes are considered which includes the scheme of prestressed steel truss-concrete composite through continuous rigid frame bridge which is proposed in this paper , steel-concrete composite box girder low-pylon cable-stayed bridge and self-anchored suspension bridge. Aiming at the prestressed steel truss-concrete composite through continuous rigid frame bridge, the design ideas are described, the general layout and the detailed construction are discussed and the mechanics property analysis in period of construction and service are also made to demonstrate the feasibility and reasonability of this scheme under given conditions . Keywords: Navigation clearance limitation, Building height limitation, Scheme comparison, Prestressed steel truss-concrete composite through continuous rigid frame bridge, Design idea, Construction feature, Mechanics property ana