从道路结构出发,对具有内、外环道的平面环形交叉路口建立了具有多个道路瓶颈的元胞自动机模型,对平面环行交叉路口的交通流进行研究.计算机模拟结果表明,环形交叉路口的内环道中与入环车道接壤处是最容易发生阻塞的地方,内环道中车辆之间的非线性相互作用的效应随刹车概率的增大而增强,流量随之减小;而转向概率的增加有助于提高系统交通流量. Based on the road structure, a cellular automaton model with multiple road bottlenecks is built for a planar roundabout with inner and outer rings, and the traffic flow at a planar roundabout is studied. Computer simulation results show that the roundabout Of the inner ring road and into the ring road bordering the most prone to block the place, the inner ring road vehicles with the nonlinear interaction effect increases with the increase of the braking probability, the flow decreases; and the steering probability Increasing helps to increase system traffic flow.