Modelling and simulation software company PTV has detailed how its PTV Vissim software models supported an innovative upgrade of a key junction in Northamptonshire that has led to a significant reduction in congestion since its opening in 2021.
As part of its improvement plans, National Highways developed an innovative scheme to upgrade Chowns Mill, a key junction between the A45 and A6.
The upgrade involved replacing the existing priority roundabout with a throughabout junction, converted into a signalised junction with traffic lanes running down its centre.
PTV Vissim was used during the development of the scheme to demonstrate the operation and capacity of the junction. It also provided parameters for coding the scheme into the strategic evaluation model.
Visualisations of the PTV Vissim model were also used in discussions with stakeholders and members of the public, who were concerned that the layout might not work effectively. The visualisations demonstrated both the level of assessment that had been carried out, and how the intersection signals would be managed to coordinate the complex mix of movements through it.
The roundabout opened in December 2021. National Highways says new layout has significantly improved congestion and has received overwhelmingly positive feedback since its completion.
(Picture – PTV/National Highways)