  Unlike most existing studies on off-ramp traffic signal control, this paper
focuses on the optimization problem of the signalized intersection connected to
freeway on-ramps. Conflicts are often observed between the traffic heading to
an on-ramp and the traffic continuing straight which leads to issues such as
intersection overflow, increased delay, and concerns about safety. For studying
this problem, a real-world signalized intersection in Buffalo, New York was
chosen, which has two through lanes and one short shared (through and
right-turn) lane. At the downstream of the intersection are two following
on-ramps, one to the highway I-290 West and the other to I-290 East. During
peak hours, the shared lane often observes a long queue, which furthermore
blocks the through traffic on the parallel lane. To solve this problem, a
VISSIM agent-based simulation model was built and calibrated based on field
observations. Three potential optimization solutions were proposed and tested
with the help of VISSIM: (1) increasing the length of the short shared through
and right-turn lane; (2) making the short shared through and right-turn lane
right-turn only, and (3) adding a new diverge lane for the right-turn vehicles.
According to the simulation results, solution (3) performs the best, resulting
in the least vehicle delay time.
