复杂城市场地下大跨度桥梁总体设计关键技术研究

以常德沅江六桥总体设计为例，分析了基于复杂城市场地下大跨度桥梁设计特点及需考虑的各方面因素，阐述沅江六桥方案的设计思路。综合考虑规划路网、沿线高压电走廊、沅江水文条件、地震断裂带等因素，对大桥的规划桥位进行优化调整，提出推荐桥位方案。根据通航要求和规划码头等条件，确定推荐方案的桥梁跨径和桥型。简要介绍桥梁结构设计，并验证主要结构的科学合理性。

Study on Key Technology of Overall Design for Long-span Bridge under Complex Urban Site

Taking the overall design of Yuan River No.6 Bridge in Changde as an example, the design characteristics and each factor to be considered for the long-span bridge under the complex urban site are analyzed, and the design ideas of Yuan River No.6 Bridge are expounded. The planned road network, high-voltage corridor along the line, hydrologic condition of Yuan River, seismic fault zone and other factors are comprehensively considered. The planned position of the bridge is optimized and adjusted. The position scheme of the bridge is proposed. According to the conditions of navigation requirements and planning wharf, the bridge span and type of the recommended scheme are determined. The design of bridge structure is briefly introduced and the scientific rationality of the main structures is verified.