Adding to our series about SimTraffic calibration, today's post focuses on the Turning Speed. Turning Speed is a simple item to code, but it can make a noticeable difference when modeling intersections with large turning radii or freeway ramps. This setting is a great place to start calibrating your SimTraffic model.

Make sure to read rest of the series; we have discussed Link OD Volumes, Lane Alignment, and the Positioning & Mandatory Distances.

We will be focusing on the westbound right turn of the intersection shown below. As you can see, it is a free-flowing channelized right-turn. With this type of geometry, drivers typically turn right at speeds approximately 5 to 8 mph higher than a typical non-channelized right turn (NCHRP 208).

Today's post is a continues our series on calibrating SimTraffic. Along with the Lane Alignment and Positioning Distances, the Link OD Volumes determine lane utilization in SimTraffic.

Located in the Volume Settings window, the Link OD Volumes window allows control over the origin and destination of two adjacent intersections. Link OD Volumes can be used to reduce or eliminate certain turn combinations, such as  preventing vehicles from turning left twice at a freeway or wide median arterial.