An Analysis of a Partially Signalized Roundabout using SIDRA 6 Software

a School of Natural Built and Environment, University of South Australia, South Australia, 5095, Australia; Email: hong_ki.an@mymail.unisa.edu.au b Same as the first author; Email: Wen.Yue@unisa.edu.au c School of Computer Science, Engineering and Mathematics, Flinders University, South Australia, 5001, Australia; Email: branko.stazic@flinders.edu.au Abstract: Normally, under unbalanced traffic volumes, roundabout metering that operates with traffic signals on one (sub-dominant) approach is used to improve roundabout operating conditions. There are few reports of studies concerning roundabout metering that operates with traffic signals on two approaches. SIDRA INTERSECTION 6 is a widely used intersection evaluation software with a roundabout metering model which allows only one approach to be signalized. This paper reports a study of roundabout metering with signals on two approaches using a SIDRA INTERSECTION 6 network model, representing the roundabout as a four-node network. The model is applied to a real-life case on Old Belair Road in Adelaide for the morning peak period (08:00–09:00 AM). Calibration methods are suggested for this analysis. The results of the analysis indicate that the level of service (LOS) and the delay time on the dominant approach are C and 23.2 seconds.