摘要:西一线绛溪河大桥为（55+175+55）m三跨连续下承式钢拱桥，大桥拱肋呈空间扭曲形态，造型轮廓确定困难，构造设计十分复杂且受到加工制造可行性限制较多。项目组运用Rhino+CATIA软件进行BIM正向设计，通过参数化建模、双曲面曲率分析优化、仿真计算及节段批量出图等方法，有效提升了大桥设计效率，优化了设计方案，节省了材料用量，大幅减少了钢结构深化设计周期与加工成本。同时，充分发挥PPP项目优势，在设计阶段即与钢结构加工单位建立起协同设计机制，考虑加工制造环节的需求，避免了后续的修改和设计变更。另外，项目组采用“三维模型交付为主，二维图纸交付为辅”的模式，通过BIM模型演示将结构构造细节逐一展示，有效保证了交付的实用性和完整性。

Abstract: The Jiangxi River Bridge on the western front line is a (55+175+55) m three span continuous through steel arch bridge. The arch ribs of the bridge are in a spatial twisted shape, making it difficult to determine the shape and contour. The structural design is very complex and subject to many limitations on the feasibility of processing and manufacturing. The project team used Rhino+CATIA software for BIM forward design. Through methods such as parametric modeling, hyperbolic curvature analysis optimization, simulation calculation, and batch drawing of segments, the efficiency of bridge design was effectively improved, the design scheme was optimized, material usage was saved, and the steel structure deepening design cycle and processing cost were significantly reduced. At the same time, fully leveraging the advantages of PPP projects, a collaborative design mechanism was established with steel structure processing units during the design phase, taking into account the needs of the manufacturing process and avoiding subsequent modifications and design changes. In addition, the project team adopts a mode of "three-dimensional model delivery as the main focus, two-dimensional drawing delivery as a supplement", and demonstrates the structural construction details one by one through BIM model demonstrations, effectively ensuring the practicality and completeness of delivery.