强制性换道的空间特征对分流区交通流的影响

为研究车辆在多车道分流区的跟驰换道行为，将强制性换道划分为激进型和保守型.在考虑驾驶员换道需求与空间位置关系的基础上，量化两种强制性换道行为的转换条件，并给出车辆强制性换道规则；对跟驰模型中的减速度参数进行优化，建立多车道下分流车辆的跟驰换道模型；采用实际数据标定模型中关键参数，并验证模型的可行性.仿真结果表明：分流车辆的横向空间分布对交通流的干扰具有显著性影响；当分流车辆集中在最左侧车道时，中间2车道的运行速度波动明显，折减量最大时达到51.4%，恢复稳定所需时间更多；通过 4组实验场景发现，分流车辆的合理空间分布对交通流运行速度有较大的改善作用.

Spatial Feature of Mandatory Lane Changing and Its Impact on Traffic Flow at Diverging Area

To examine the vehicle following and lane- changing behaviors at multiple lane diverging area, this study classified the mandatory lane-changing behavior into aggressive and mild mandatory lane-changing behaviors. Based on the relation between the desire of lane-changing and vehicle position, this study quantified the transformation conditions of the aggressive and mild mandatory lane- changing behaviors. The rules of lanechanging behavior of diverging vehicle were proposed by optimizing the deceleration factor of car- following model. The car- following and lane-changing model for the multiple lane diverging area was then developed and the critical parameters were calibrated. The model was validated by the real data. The result shows that the spatial distribution of diverging vehicles at each lane have significant impact on the stability of traffic flow. When the leftmost lane has high density of diverging vehicles at, the middle two lanes would experience significant speed. The maximum reduction rate of vehicle speed was 51.4% , and takes longer time to restore the traffic flow stability. Based on the analysis of four different scenarios, the average speed could be significantly improved by reasonable spatial distribution of diverging vehicles.