ARCADY 5 (UK) USER GUIDE

ARCADY 5 (Assessment of Roundabout CApacity and DelaY Version 5) is a computer program for predicting capacities, queue lengths and delays (both queueing and geometric) at non-signalised roundabouts and mini-roundabouts. It can also be used to predict accident frequencies or indices for a particular layout from information about traffic flow and site data. The program is used as a tool by junction design engineers to help them to assess their designs. It is used primarily for modelling peak periods and can be applied to any single-island roundabout with 3 to 7 arms and any mini-roundabout with 3 or 4 arms. ARCADY 5 is the first version of ARCADY to incorporate the result of extensive research into the factors affecting capacity and accident risk at mini-roundabouts. The user guide describes animation; graphical-assisted data entry, and a new feature allowing batch processing of data files. A comprehensive context-sensitive help system is also integrated in to the program. Other topics in the guide include a description of the theory and research incorporated in ARCADY, how an ARCADY model should be specified and the way data are entered using its graphical user interface (including guidance on how to measure data). Also described is the output and how it should be interpreted. A number of examples have been included to aid the understanding of different roundabouts and the modelling problems they pose. (A)