车联网环境对城市快速路驾驶安全的影响评价

为明确不同情形下车联网对城市快速路交通安全的影响程度，首先，在分析车联网对快速路驾驶行为影响的基础上，对车联网和常规驾驶环境下的驾驶模型参数进行了标定；然后，选取累计碰撞时间（Time Exposed Time-to-collision, TET）和积分碰撞时间（Time Integrated Time-to-collision，TIT）指标对快速路纵向驾驶行为进行安全评价，选取侧向碰撞风险（Sideswipe Crash Risk, SSCR）作为快速路横向换道驾驶安全的评价指标；最后，基于VISSIM设计快速路进行仿真试验，考虑车联网和常规驾驶环境，研究不同渗透率和饱和度条件下网联车对纵向追尾和横向换道驾驶行为的安全影响程度。研究结果表明：车联网环境下网联车渗透率对快速路驾驶行为的影响呈现出缓慢提升（0～50%）、快速提升（50%～75%）及显著提升（75%～100%）三阶段，其中TET指标分别对应降低14.57%, 30.10%和49.01%；车联网环境下，交通饱和度对快速路的交通安全影响则呈现出先快后慢的改善趋势。当网联车渗透率超过75%之后，交通安全提升程度最为明显；车联网环境中，当快速路交通饱和度低于0.8时，交通安全改善程度更为显著。

Influence Evaluation of Internet of Vehicles Environment on Driving Safety of Urban Expressway

In order to understand the influence degree of Internet of Vehicles (IOV) on urban expressway traffic safety under different situations, firstly, the influence of IOV on the driving behavior of expressway was analyzed, and the driving model parameters under IOV and normal driving environment were calibrated. Then, Time Exposed Time-to-collision (TET) and Time Integrated Time-to-collision (TIT) were selected to evaluate the safety of longitudinal driving behavior, and the Sideswipe Crash Risk (SSCR) was selected as the evaluation index of the lateral lane changing driving safety. Finally, based on the VISSIM design of the expressway simulation experiment, considering the IOV and conventional driving environment, the safety impact of the internet vehicles on the longitudinal rear-end and lateral lane-changing driving behavior under different permeability rate and saturation conditions were studied. The research results show that under the environment of the IOV, the influence of the penetration rate of the internet vehicles on the driving behavior of the expressway presents three stages: slowly increasing (0~50%), rapidly increasing (50%~75%), significantly increasing (75%~100%), and TET decreases by 14.57%, 30.10% and 49.01% respectively; The influence of traffic saturation on the traffic safety of expressway shows a trend of improving from fast to slow; When the penetration rate of the internet vehicle exceeds 75%, the traffic safety improvement degree of traffic safety is the most obvious; When the traffic saturation of expressway is lower than 0.8, the improvement of traffic safety is more significant.