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  • Windows XP/Vista/7/8

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Assessment of Roundabout Capacity and Delay

Prediction of capacities, queues, delays and accidents at roundabouts

"TRL has emerged as a leader in training and software, INDOT was very fortunate to adopt ARCADY. We now have 50 INDOT engineers trained and fully engaged in investigating all of our upcoming projects for the feasibility of using a roundabout." John Wright, Indiana Department of Transportation.

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 8 can model:

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

Entry Lane Simulation

ARCADY 8’s Entry Lane Simulation tool enables full simulation of individual entry 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.

Save Time Incorporating ARCADY into your BIM Workflow

The ARCADY-AutoTrack Link is available to all users of ARCADY 8 to allow for "on-the-go" analysis of roundabout CAD designs, saving valuable time and money. Since the acquisition of Savoy Computing (developers of AutoTRACK) by Autodesk®, ARCADY 8 has been updated to support the new product, Autodesk® Vehicle Tracking.

Other new features in ARCADY 8

  • The HCM 2010 Roundabout Capacity Model has been included in ARCADY 8 for international customers requiring different analysis models.
  • Simplified options for modelling linked roundabouts (first introduced in ARCADY 7).
  • Bypass flows at roundabouts can now be explicitly specified.
  • Residual Capacity mode quantifies the ‘spare’ capacity at any roundabout.
  • Junction results show demand-weighted delay and LOS for the whole roundabout. 

Further Information

Further details about the individual versions of ARCADY can be found in the support section.

Forthcoming Training Courses

  Course Dates Location Cost*  
View Details ARCADY / PICADY Workshop 01 Jul 2015 Crowthorne £320 Add to Basket
View Details ARCADY / PICADY WORKSHOP 08 Sep 2015 Crowthorne £320 Add to Basket
View Details ARCADY / PICADY Workshop 04 Nov 2015 Crowthorne £320 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