Hi all,
I am simulating three independent actuated_uncoordinated signals. Here I have three issues to get clarification.

1. Basically the right turn queues showing up in simtraffic are very high. This situation is not for all scenarios. In some cases, though the right turn volumes are low, the queues are high. There are no Queueing penalties or storage block time (in the report). But in simulation I see that some right turn vehicles are being blocked because of the thru traffic. Changing turning speed did not help much.

2. The 95th Queues reported are more than Maximum queues? How can this be? I am using PHFs. This situation is not specific with right turn vehicles. Its observed with many turning mvmts.

3. One of the intersections LOS is really low because of the traffic in almost all turning mvmts. This is shown up in synchro. The simtraffic report delays are also close to synchro network (whole intersection with the links) delays. But the simulation graphically doesnt seem so. Vehicles move really smoothly and there seems to be not much delay or stop times at all.

Any ideas and thoughts will help me a lot.

Thanks a bunch

Simha

Simha,

1. A vehicle is considered queued whenever it is traveling at less than 10 ft/s (3 m/s). A vehicle will only become queued when it is either at the stop bar or behind another queued vehicle.
2. The 95th Queue is equal to the Average Queue plus 1.65 standard devidations. The 95th Queue is not necessarily ever observed, it is simply based on statistical calculations.
3. SimTraffic reports the observed values from the simulation model history file. The animation and output should be consistent in their results. If you cannot explain it, send the file to support@trafficware.com and we will look it over.

Sincerely,
Jeff Gerken