基于路径选择的高速公路事故影响范围分析
Analysis of expressway traffic accident influence scope base on route choice

为了在高速公路事故发生后给驾驶人提供及时有效的信息，将事故影响程度和损失降到最小，对高速公路交通事故在无外界干预情况下的影响范围进行了分析研究。首先对Logit路径选择模型和BRT阻抗函数进行改进，同时考虑收费站对路阻函数的影响，采用改进模型对事故点上游的车辆路径重新分配进行研究，用容量限制？捕嗦肪督煌ǚ峙浞椒ǘ跃植柯吠？进行交通流重分配，得到事故条件下各路段流量，并将交通影响评价中判定新建项目区域交通影响大小的方法的思想应用到事故影响范围确定上，给出高速公路交通事故影响范围的思路，根据路段服务水平变化情况，对事故影响范围进行确定。最后以给定网络为依据，对事故发生后路网上出行者的路径选择及事故影响范围进行例证分析。研究结果表明：高速公路上事故的发生会导致临近路网的饱和度上升，但事故对不同路段的影响程度不同，在路径选择基础上，结合路网通行能力，服务水平等数据；根据算例分析可知，该模型可用于事故影响范围的准确告知，且符合实际道路环境情况，根据影响程度分级对高速公路采取合理的管制措施，有利于有效疏散交通，降低事故影响。 ？？
To provide drivers with timely and effective information after the occurrence of a expressway accident, and to minimize the impact of and loss resulting from the accident, the scope and extent of the impact caused by a expressway accident without external intervention were analyzed. First, the Logit route selection model and BRT impedance function were improved. Meanwhile, the impact of the toll station on the impedance function was considered. Second, the use of the improved model to redistribute routes of vehicles upstream of the accident point was analyzed. The capacity limitation multiroute traffic distribution method was adopted to redistribute the traffic flow in the local expressway network into the traffic flow of each road section in the case of accident occurrence. Moreover, the method of measuring the impact of the local traffic of newly built projects in traffic impact evaluation was used to determine the impact scope of the accident and to provide innovative ideas to measure the impact scope of expressway accidents. According to changes in the service level of each road section, the impact scope of the accident was determined. Last, a given highway network was taken as a case study to analyze the route selection of drivers on this network after an accident and the impact scope of the accident. According to analysis results, the occurrence of the expressway accident increases the saturation level of its adjacent road networks, and the extent of impact of the accident varies in different road sections. Based on the route selection of drivers and combined with data concerning the highway network capacity and service level, the case study results prove that this model can be used to forecast the impact scope of an accident accurately, and the forecast is in accordance with the actual situation of the highway environment. Therefore, taking proper control measures on highways based on the impact extent of an accident can help achieve effective evacuation of traffic and reduce the impact of the accident. 2 tabs, 9 figs, 25 refs