TRAFFIX™ implements the Circular 373/1994 HCM method, the 1997 HCM method, and the 2000 HCM method for calculating the capacity and level of service for All-Way Stop Controlled Intersections. To insure an unsignalized calculation, for three-way and all-way stop conditions, all of the approaches must be coded as “Stop” in the geometry screen.
Stop sign control is selected in TRAFFIX™ in three ways. 1) When the network is initially drawn, the “Four-Way Stop Intersection” tool can be used to place a node which has all-way stop control. 2) This tool can also be used to change an existing node to a “Four-Way Stop Intersection” node. 3) At an “Unsignalized Intersection” node, the control method will be changed to “Four-Way Stop” by selecting “Stop” for all approaches in the Geometry…Control screen.
The user should ignore any signal related output by TRAFFIX™ (such as g/c times, cycle length, loss times) when stop sign control has been selected for the intersection. The above stop sign method does not calculate average queue lengths, so this information is not available from TRAFFIX™ when stop sign control has been selected.