基于安全间距的T型交叉口临界间隙分析

Analysis of Critical Gaps at T-type Intersection Based on Safe Distance

对于无信号T型交叉口,找出临界间隙的合理分布估计对研究交通行为控制有重要意义。考虑主路车流车头时距分布对临界间隙的影响,在汽车安全行驶间距模型基础上,运用运动学原理分析了安全间距条件、通过时间条件以及车头间距、车头时距与速度的关系,给出了临界间隙的表达公式。通过Matlab模拟计算比较,证明用WU Ning的方法计算临界间隙,泊松分布比以往直接套用的正态分布和对数正态分布更适合。

For an unsignalized T-type intersection, it is very important to find out the reasonable distribution of critical gaps for studying traffic behavior control. Considering the impact of time headway distribution on the critical gaps, and analyzing the conditions of safe distance, passing time, and the relation among space headway, time headway and speed using the principle of the kinematics with the vehicle safety distance model, an expression formula of critical gap was constructed. Through Matlab simulation comparison, it was proved that using WU＇s method to calculate poisson distribution and the critical gaps would be better than directly using normal distribution and lognormal distribution.