基于解析分析方法的多塔悬索桥中塔刚度区间研究

Determination of the mid-tower lateral stiffness is critical in multi-tower suspension bridge design. Currently, the design of the mid-tower depends on the bridge model via verifying whether the selected mid-tower sizes satisfy the structural global performance requirements and still lacks more direct computation approach. In addition, the feasible mid-tower stiffness not only locates in a range but also behaves sensitively to the randomness of the structural parameters. This project aims to develop a deterministic mid-tower stiffness range analytical model, manifest the mechanism of the mid-tower effect, identify the critical parameters to the mid-tower stiffness range based on dimensionless analysis method, quantify the effect of the structural parameters’ randomness using an inverse reliability method, yield the mid-tower stiffness range chart, which can be applied in practice, and finally propose improvements for the traditional multi-tower suspension bridge to overcome the restriction of the mid-tower effect and find out the corresponding optimal structural parameters using the swarm-based search algorithms. The research results will provide a direct approach to the design of mid-tower in multi-tower suspension bridges, enhance and perfect the multi-tower suspension bridge’s computation and analysis methods.

中塔侧向刚度的确定是多塔悬索桥设计的关键问题之一。目前中塔刚度的设计需依赖于全桥模型，通过验算桥塔尺寸是否满足结构整体性能要求的间接方式获得，尚缺少直接的计算方法。此外，多塔悬索桥合理的中塔刚度不仅具有区间性，其对结构参数的随机性也较为敏感。本项目采用解析法建立确定性的多塔悬索桥中塔刚度区间模型，揭示“中塔效应”产生的机理，通过无量纲分析法识别出影响中塔刚度的关键因素；利用逆可靠度方法量化参数随机性对中塔刚度的影响，进而获得可指导设计的中塔刚度区间图；最后提出突破 “中塔效应”对常规多塔悬索桥制约的结构改进措施并基于群搜索算法得到与之对应最优结构参数。研究成果将为多塔悬索桥中塔刚度设计提供新途径，能进一步丰富和完善多塔悬索桥的相关计算理论和分析手段。

中塔侧向刚度的确定是多塔悬索桥设计的关键问题之一。目前中塔刚度的设计需依赖于全桥模型，通过验算桥塔尺寸是否满足结构整体性能要求的间接方式获得，尚缺少直接的计算方法。本项目根据多塔悬索桥的受力特点，采用解析法建立多塔悬索桥中塔刚度区间模型，揭示“中塔效应”产生的机理，通过无量纲分析法识别出影响中塔刚度的关键因素，获得可指导设计的中塔刚度区间图；提出突破 “中塔效应”对常规多塔悬索桥制约的结构改进措施及相应的解析分析模型，相较于传统的多塔悬索桥，采用主跨主缆采用中央扣与加劲梁相连接可有效提高结构的整体刚度，减小中塔的刚度需求从而节省建造成本；针对多塔悬索桥结构复杂、控制参数多、设计难度大的特点，发展了一种基于群搜索算法非经验主导的复杂结构桥梁设计方法。本项目执行期共发表SCI论文12篇、中文核心论文2篇，其中包括Journal of Bridge Engineering, Journal of Computing in Civil Engineering, Engineering Structures, Structural and Multidisciplinary Optimization等国际高影响力期刊。依托本项目共指导毕业三名硕士研究生，协助指导博士研究生一名。