Spatio-temporal dynamics of jams in two-lane traffic flow with a blockage

A two-lane traffic model is presented to investigate traffic jams induced by a car accident. The model is an extension one of the optimal velocity model taking into account lane changing in the open flow. We study the jammed states and the fine structures of jams. It is shown that there are two kinds of jams: one is the localized jam just behind the car involved in the accident and the other is the extended jam. The jamming transition from the localized jam to the extended jam occurs with increasing inflow density. The extended jam exhibits the fine spatio-temporal structure. The local density fluctuates highly at the edge of jam. The number distribution of lane-changing cars is derived for both jams.