中文摘要：

运用离散优化方法，研究区域内各组团间运输通道网络优化设计问题，设定运输通道供给能力以及通道在区域之间的运输时间约束，构造综合运输通道投资建设总费用的优化模型，考虑各种运输通道的单位投资建设费用和建设长度的最优问题；利用综合运输通道的特点和区域组团网络结构进行算法设计，并给出最优解的多方案求解步骤；针对大规模节点采用遗传算法进行求解可以提高求解效率；通过一个算例，对模型和算法的可行性和有效性进行验证，说明该算法可得到综合运输通道的最优投资方案，使综合运输通道满足规划年的客货运需求，以及各种运输方式的平均出行时间满足要求，分析说明客货运输需求与运输通道建设的关系，结果表明提出的模型与算法对交通投资项目提供较好的辅助决策支持。

英文摘要：

Optimal network design for transportation corridors of regional space groups is studied by using combinatorial optimization. The optimal investment model of multimodal transportation corridors is formulated by establishing supply capacity constraint and travel time constraint of transportation corridors. The unit investment cost and the length of transportation corridors is synthetically considered in the model. A method is designed by considering the characteristics of multimodal transportation corridors and the network structure of regional groups, and computational schemes are provided. The efficiency of solution is improved by using a genetic algorithm for large number of nodes. The feasibility and effectiveness of the model and the algorithm is verified through examples, which indicate that the optimal investment scheme is identified to meet transportation demands for planning and the average travel time of each transportation mode. The relationship between transportation demands and transportation corridor design is analyzed, and the results indicate that the model and the solution could be a promising approach to improving the traffic investment programs.