菱形立交分流区主线线形指标分析

为确定菱形互通式立交分流区域主线线形指标,分析了菱形互通式立交分流处的交通事故特征,运用汽车理论、交通心理学及人机工程学获取菱形立交分流区的识别视距,运用VB程序开发软件及高速公路横净距设置条件建立菱形立交区域主线平面及纵断面指标和识别视距关系模型,提出菱形立交分流区满足识别视距要求的主线圆曲线半径及凸形竖曲线半径值.结果表明:对待建菱形立交分流区应分析识别视距,并用识别视距对主线线形指标验算;对已建成菱形立交分流区,应加强安全保障措施,保证主线及驶离主线车辆行车安全.

Analysis on mainline alignment index in diamond interchange diverging areas

The characteristics of traffic accidents is analysed in order to determine the mainline alignment index in the diamond interchange diverging areas. The recognition sight distance of the diamond interchange diverging areas by combining the automobile theory, traffic psychology and ergonomics,and simultaneously are acquired. Based on the VB software and the setting conditions of the lateral clear distance of the expressway, the relation model between the indicators of the mainline plane and vertical section and the recognition sight distance in the diamond interchange diverging areas is set up. The values of the circular curve radius and the convex vertical curve radius of the mainline which meets the requirements of the recognition sight distance in the diamond interchange diverging areas is obtained. The analysis results show that it is necessary to analysis to the recognition sight distance of the diamond interchange diverging areas to be constructed and check the alignment index of the mainline with the recognition sight distance, for the constructed diamond interchange diverging areas, it is necessary to strengthen the safety precautions so as to guarantee the traffic safety of vehicles driving on the mainline and off the mainline.