A new nm-vehicle traffic flow simulation model, named as MD-EBCA, was proposed, in which the phenomemon of riding against the traffic flow was considered.The proposed model was used to explain the mechanism for the formation of the m-vehicle and nm-vehicle mixed traffic flow.According to the behaviors of nm-vehicles,the new model enables the nm-vehicles to move in both logitudinal and lateral direction.The traffic phenomemon of the nm-vehicle flow on ordinary roads which are equipped with road fences or those which are not equipped with road fences were analyzed speperately through the spatial-temperal diagram and the fundamental diagram.The simulation result showed that the free flow is presented on the nm-vehicle road when the road density is less than the critical density,and the linear relationship between the average flow rate and nm-vehicle numbers can be observed.The phase transition F-J are suggested by observing the spatial-temporal patterns in high density when the nm-vehicle road is completely isolated from the m-vehicle lanes.When the nm-vehicle road is not isolated from the m-vehicle lanes, the phase transition F-S can be observed in the same high density,and the m-vehicle and nm-vehicle mixed traffic flow is finally formed as the aggressive riders enter the m-vehicle lanes and return back to the nm-vehicle road when the traffic turns better.
