How many times have you been caught in a traffic jam without apparent cause? Although there are no works, accidents, or peak time, you can get to form traffic jams, are called “ghost retention.”
According to science, there are two factors in every traffic jam: the capacity of the road (volume of vehicles that can be transported) and the intensity of the service (traffic demand). The relationship between both defines the level of service. In order for the road to be congested, the volume of vehicles must be close to its capacity.
When reaching this capacity, certain elements such as a braking, a sudden change of lane or an accident in the opposite lane can cause a vehicle to reduce its speed producing a domino effect that triggers a retention.