双车道公路驾驶人的超车行为是最为复杂与危险的驾驶行为之一，由于双车道公路超车而导致的交通事故数量与伤亡人数均占有较高比例。本项目拟基于双车道公路驾驶人超车安全评价开展附加车道设置条件、效益评估与几何设计研究。项目的研究目标与创新之处在于：1)构建双车道公路驾驶人超车冲突时间与车速、交通量的关系模型，提出双车道公路驾驶人超车安全评价方法；2) 给出双车道公路附加车道设置的交通量条件、线形条件及地形条件；3) 提出双车道公路附加车道设置的安全改善效益与效率提升效益计算方法，给出双车道公路附加车道在平原区、丘陵区及山岭区的适用性分析方法；4)提出双车道公路附加车道合理设置间距、设计长度、宽度与渐变段长度计算方法。研究成果可丰富道路线形设计与驾驶人行为研究理论成果，并为公路规划、设计、建设与管理部门提供设计依据与决策参考。

Drivers' overtaking maneuver on two-lane highway is one of the most complicated and dangerous behavior. The proportion of accident amount and fatalities due to overtaking on two-lane highway have been very high. In this project, driver's overtaking maneuver safety evaluataion, auxiliary lane's setting conditions, benifit evaluation and geometric design will be studied. The innovations of this project include: 1) establishing relationship among overtaking conflict time, speed, traffic volume and traffic composition, and presenting driver’s overtaking safety evaluation method on two-lane highway; 2) presenting traffic volume requirements, highway alignment requirments terrain requirments for setting auxiliary lane on two-lane highway; 3) establishing safety and efficiency improving benefit calculaiton mothod of setting auxiliary lane on two-lane highway, and putting forward analysis method of auxiliary lane applicability for plain region, hilly region and mountain region; 4) presenting calculation method of two-lane highway’s auxiliary lane length, width and transition section length. It is expected to not only enrich theoretical research fruits of road alignment design and driver behavior, but also provide planning, design, construction and management department with basis and reference.