中文摘要：

为提高公路网对经济社会发展的适应性,针对区域公路网布局优化问题,以建设成本、土地占用机会成本、运输成本、公路网使用效率四因素为决策变量,构建公路网四因素指数。根据公路交通资源的分布特征将区域公路网布局形态划分为分散型布局和集中型布局,以四因素指数为支撑,对两种布局形态的性能特征进行比较分析,从三节点公路网的布局形态入手,分析节点位置、交通需求分布对两种布局形态四因素指数的作用规律,最后以广州—湛江运输通道为例,分析复杂情景下两种布局形态的四因素指数。研究结果表明：公路网四因素指数可综合反映公路网系统功能及其对社会经济发展的贡献,方便布局方案的评价和比选;集中型布局在土地集约利用、交通运行效率等方面具有明显优势,是区域公路网布局优化的有效选择。

英文摘要：

In order to improve the applicability of road network to economic social development,aiming at the issue of regional road network optimization, taking the factors of construction cost, land occupation opportunity cost,transportation cost and road network efficiency as decision variables,4-factor index of road network is built up. The regional road network layout is divided into distributed type and centralized type according to the distribution characteristics of road infrastructure. The performance characteristics of the 2layout types are comparatively analyzed on the basis of the 4-factor index. The influence of node location and traffic demand distribution on the 4-factor indices of the 2 layout types is analyzed using the 3-node road network layout. Finally,taking Guangzhou- Zhanjiang corridor as an example,the 4-factor indices of the 2layout types under complicate conditions are analyzed. The result indicates that（ 1） the 4-factor index of road network can comprehensively reflect the systematic function of road network and its contribution to economic social development,it can make the evaluation and comparison of network layout schemes simple and convenient;（ 2） the centralized type performs very well in land intensive utilization and traffic efficiency,which is an effective choice for regional network layout optimization.