Gulf Coast Research Center for Evacuation and Transportation Resiliency Louisiana State University, Baton Rouge, LA 70803, United States.
Accid Anal Prev. 2011 Sep;43(5):1610-6. doi: 10.1016/j.aap.2011.01.006. Epub 2011 Apr 30.
The two-fluid model for vehicular traffic flow explains the traffic on arterials as a mix of stopped and running vehicles. It describes the relationship between the vehicles' running speed and the fraction of running vehicles. The two parameters of the model essentially represent 'free flow' travel time and level of interaction among vehicles, and may be used to evaluate urban roadway networks and urban corridors with partially limited access. These parameters are influenced by not only the roadway characteristics but also by behavioral aspects of driver population, e.g., aggressiveness. Two-fluid models are estimated for eight arterial corridors in Orlando, FL for this study. The parameters of the two-fluid model were used to evaluate corridor level operations and the correlations of these parameters' with rates of crashes having different types/severity. Significant correlations were found between two-fluid parameters and rear-end and angle crash rates. Rate of severe crashes was also found to be significantly correlated with the model parameter signifying inter-vehicle interactions. While there is need for further analysis, the findings suggest that the two-fluid model parameters may have potential as surrogate measures for traffic safety on urban arterial streets.
车辆交通流的二流体模型将干线交通解释为停止和行驶车辆的混合。它描述了车辆行驶速度与行驶车辆比例之间的关系。模型的两个参数本质上代表了“自由流”行驶时间和车辆之间的相互作用水平，可用于评估城市道路网络和部分限制通行的城市走廊。这些参数不仅受到道路特征的影响，还受到驾驶员群体行为方面的影响，例如攻击性。本研究对佛罗里达州奥兰多的 8 条干线进行了二流体模型估计。二流体模型的参数用于评估走廊级别的运行情况，以及这些参数与具有不同类型/严重程度的碰撞率之间的相关性。在后车碰撞和角度碰撞率方面，发现二流体参数之间存在显著相关性。严重碰撞的发生率也与表示车辆间相互作用的模型参数显著相关。虽然需要进一步分析，但研究结果表明，二流体模型参数可能有潜力作为城市干道交通安全的替代指标。
