Hello everybody:

Here is a situation. I am asked to look at the options of improving
intersection capacity of very congested intersections of an arterial. The
arterial is 5 lane road with center lane serving as two way left turn lane.
There is not enough right of way to add another lane to improve the congestion
and capacity. However, DOT wants to look at different options to improve the
capacity. One of the options I am considering is to run simtraffic and get
queue length assuming we can add one lane in each direction at the
intersection. The existing condition results shows that there is high number
of through queues at the intersections. It would be nice if we could add one
through lane throughout the network, however it cannot be done because of some
constraints. Therefore, I want to run simtraffic model adding one through lane
on upstream and downstream of intersection up to certain distance. The
distance will be depend upon the queue results obtained from simtraffic
output. The addition lane will be reduced back to two lane after certain
distance on both approaches. I was wondering if i could get any reference
regarding this kind of study done in the last. I would appreciate your input.
Thank you.