在公路网规划中 ,常常涉及到对包含若干公路建设项目的方案进行比选、经济评价以及建设项目排序等问题。事实上 ,这些建设项目之间往往具有相互竞争或协作的关系。当项目之间存在竞争、协作关系时 ,方案所产生的经济效益会因项目的组合和建设顺序的不同而异。研究分析了建设项目之间各种关系产生的内在机理 ,探讨了其在公路建设项目分析中的主要用途并给出了基本的分析方法 In the road network planning, often involves the selection of a number of road construction projects, economic evaluation and construction projects and other issues. In fact, these construction projects often have competing or collaborative relationships. When there is competition and cooperation between projects, the economic benefits arising from the programs will vary according to the combination of projects and the order of construction. This paper studies and analyzes the internal mechanism of the various relations among construction projects, discusses its main uses in the highway construction project analysis and gives the basic analysis methods