Abstract: With the rapid development of economic and road transportation industry, freeway expansion may become the new hot spot for future road construction. In the expressway unilateral widening project retaining median barrier of the primary road, only in the interchange and service area near the entrance to the central median cut openings for vehicle access, which can greatly reduce the difficulty of construction, save the cost of the project, and improve vehicle operation the safety and comfort. To ensure program reliability of vehicle running into the openings, interweavement theory, traveling through space theory and queue theory are used to analyze program of median barrier opening length. Traffic control scheme is proposed based on the road traffic psychology, traffic engineering, road traffic safety engineering and driver safety, and comfort, etc. The theory of driving workload and simulation experiments verify that the technical solutions is safe and comfortable.

Key words: highway transportation, expressway changement and extendibility program, drive workload, median barrier, safety and comfort 

摘要： 随着我国经济和公路交通运输业的快速发展，高速公路扩建将成为未来中国道路建设的新热点.保留老路中央分隔带的高速公路单侧加宽工程，仅需在互通式立交及服务区出入口附近进行中央分隔带开口处理以供车辆出入，可大大降低工程施工难度、节约工程成本、提高车辆运行的安全舒适性.为了保证中央分隔带开口技术方案的可靠性，本文基于交织理论、可穿越间隙理论、排队论等相关理论分析了中央分隔带开口长度方案；基于道路交通心理学、交通工程学、道路交通安全工程和驾驶员安全舒适性等原理与技术提出了交通控制方案；采用驾驶工作负荷理论和技术通过模拟仿真实验验证了技术方案的安全舒适性.

关键词: 公路运输, 高速公路改扩建, 驾驶工作负荷, 中央分隔带, 安全舒适性