Research On Fine Modeling Method Based On Three-phase Traffic Flow Theory

The solution to traffic problems requires clarifying the internal mechanisms of the transportation system and mastering the evolution laws of traffic flow.Traffic simulation modeling,as one of the important methods of traffic flow theory research,is the process of theoretical analysis or optimization of complex traffic phenomena by assuming or reproducing the operating conditions of the traffic system.Three-phase traffic theory,because its interpretation of traffic phenomena such as traffic phase is consistent with the actual situation,has been recognized by many scholars,and has become a hot spot of traffic flow theory research.Based on the three-phase traffic theory,this paper constructs a refined dual cruise-control limit model and an improved dual cruise-control limit model.The models are simulated with cellular automata,and the simulation results are analyzed and studied in depth.In this paper,the work completed follows:（1）In this paper,a refined dual cruise-control limit cellular automata model is established under the three-phase traffic theory.Inspired by the cruise-control limit rule,this refined model designs high-speed or low-speed vehicles that are not affected by noise.In addition,it introduces the slow to start rule for stationary vehicles with only one free unit in front.The computer simulation results show that whether the initial distribution is homogeneous,dense or random,the refined model can successfully reproduce the empirical characteristics of the three-phase traffic theory,including the three phase distribution characteristics and phase transformation characteristics.Furthermore,it also finds that the slope of the linear synchronous flow varies with the delay probability and the maximum value of low velocity v _LMin the synchronized flow region.Under homogeneous distribution,the linear synchronous flow with double slopes is first discovered.Under random distribution,all possible co-existence phases of three-phase traffic flow are presented in the fundamental diagram.（2）On the basis of refining the double cruise driving limit,adding a new slow-to-start rule,an improved dual cruise-control limit model is constructed.The simulation results of the improved double cruise control limit model are more suitable for the actual road traffic situation.The model can simulate three traffic phases:free flow,synchronous flow and wide moving jam.And the simulation results of fundamental diagram are qualitatively consistent with those of previous models under the three-phase traffic theory.By adjusting the model parameters,many traffic flow patterns like synchronous flow and wide moving jam that consistent with the relevant traffic constants can be obtained.