沙尘环境下交通流跟驰模型及仿真

沙尘环境下，沙、尘土及其他异物会影响驾驶员的视线，让驾驶员额外增加辨别道路条件和周围交通状况的反应时间，带来一定的交通安全隐患.为探讨沙尘环境对道路交通流的影响，本文建立了基于沙尘环境下驾驶行为的跟驰模型(SDM).线性稳定性分析和数值模拟结果表明：沙尘环境下，SDM的稳定区域缩小，交通流出现小的扰动后，难以恢复到稳定状态；而且，交通流受沙尘影响越严重，车辆速度的离散性越大，加速度的波动幅度也越大.可见，沙尘环境使交通流处于不安全的状态，易引发道路交通事故.

Numerical Simulation of Car-following Model in Sand-dust Environment

Driver's sight would be affected by sand-dust environment, resulting in additional reaction time to identify road and traffic conditions, which may cause safety problems. To explore the impact of sand-dust environment on traffic flow, this study proposes an extended car-following model based on driving behaviors under sand-dust environment (SDM). Through linear stability analysis and numerical simulation, the results show that the unstable region of SDM enlarges with increasing the value of the parameter α, which indicates that it can weaken the stabilization of traffic system. Besides, the more severely the traffic flow is affected by sand-dust environment, the greater the dispersion of vehicle speed will be, and the wider the fluctuation range of acceleration will be. Therefore, the sand-dust environment will lead to traffic flow involved in unsafe state, which increases traffic accident probability.