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System Requirements

  • Windows XP or above

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Assessment of Roundabout Capacity and Delay

Prediction of capacities, queues, delays and accidents at roundabouts

ARCADY is available as the Roundabout Module in Junctions 9.

ARCADY is based on three decades of research and development by TRL and is used for predicting capacities, queues, delays (both queueing and geometric) and accident risk at roundabouts. ARCADY is an easy-to-use and essential tool for the busy traffic professional wanting to design new roundabouts and assess the effects of modifying existing sites.

Roundabouts are modelled using the well-established TRL/Kimber capacity relationships (the ARCADY Model), which take into account key roundabout geometries such as entry width, approach width, flare length, conflict angle, inscribed circle diameter and entry radius. This empirical framework intrinsically links roundabout geometry to driver behaviour and in turn to predicted capacities, queues and delays. 

ARCADY has been successfully used to design and improve a great number of roundabouts throughout the world. It has a host of satisfied customers including governments, multinational organisations and academic institutions. Its simple and intuitive interface means that it can be used effectively by everyone, in a relatively short space of time.

ARCADY 9 can model:

  • Roundabouts
  • Mini Roundabouts
  • Linked Roundabout Networks
  • Large or Grade Separated Roundabouts
  • Pedestrian Crossings (Signalled, Unsignalled and Adaptive)

Lane Simulation

First introduced in ARCADY 8, the Lane Simulation tool allows simple simulation of individual lanes to be performed on existing ARCADY models. The user can quickly see where unbalanced queuing may occur and if lane starvation may take place. The simulation takes into account the geometric layout of the roundabout, turning proportions and user-specified lane designations. Lane movements can then be altered easily using the roundabout diagram to explore and identify the optimum lane configuration.

If combined with the OSCADY module, it is possible to set up and model part signalised roundabouts, including signals on circulating lanes.

New features in ARCADY 9

Further Information

Forthcoming Training Courses

  Course Dates Location Cost*  
View Details ARCADY PICADY Course Day 1 18 Sep 2018 Crowthorne £340 Add to Basket
View Details ARCADY PICADY Course Day 2 19 Sep 2018 Crowthorne £340 Add to Basket
* The cost is per delegate and excludes VAT.

Forthcoming Webinars

There are no webinars currently planned but please check this page regularly