BUS PRIORITY OF SCOOT EVALUATED IN A VISSIM SIMULATION ENVIRONMENT

The Split Cycle Offset Optimization Technique, SCOOT, provides opportunities for bus priority options while also reducing delays for all traffic. A connection between an actual SCOOT system and the simulation VISSIM has been developed to evaluate bus priority performance. A Salt Lake City, nine-intersection modeled corridor evaluates SCOOTs performance, both with and without bus priority. The SCOOT analysis is compared to an actuated-coordinated optimal signal timing developed in SYNCHRO. The modeling includes the existing 7- routes on the corridor. A single route with a range of bus headways is also modeled to evaluate the impacts priority with increasing bus frequency. The results indicate that SCOOT with bus priority, compared to the actuated-coordinated timing, reduces non-bus vehicle delays by 16% or 4.4 seconds per person per intersection and bus delays by 27% or 9.2 seconds for the 7-route system. Without bus priority, SCOOT reduced non-bus person-delay by 21% or 5.9 seconds per person and bus person-delay by 5% or 1.8 seconds per person. SCOOT's bus priority can reduce transit delay with a minimal impact to other traffic