- Examples of SIDRA INTERSECTION Application and Validation Studies
- Ferntree Gully Rd - Scoresby Rd, VIC, Australia
- Road corridor in the historical city of Lucca, Tuscany, Italy
- US study of alternative traffic models for signalised intersections
- Fitzsimons Lane - Porter St Roundabout, Melbourne, VIC, Australia
- Richmond Rd & Garfield Rd Intersection, Marsden Park, NSW, Australia
- US study on SIDRA roundabout model
- US study on travel time function
- South Australian study on fuel consumption
Actuated Signalised Intersection
The SIDRA INTERSECTION estimates of performance measures for actuated signals were found to be highly accurate based on the results of real-life surveys at an intersection in Melbourne, as seen in the graphs below.
Recent research on actuated signal timing and performance evaluation and its application in SIDRA 5. Compendium of Technical Papers (CD). 67th Annual Meeting of the Institution of Transportation Engineers, Boston, USA.
Results of extensive research on actuated signal control methods are presented. A method for predicting actuated signal timings, and analytical models for predicting various performance statistics (delay, queue length, queue clearance time, proportion queued), that are implemented in the SIDRA software package are described. With actuated signal timings, equal degrees of saturation do not necessarily result, and the minor movements may get lower degrees of saturation than the major movements, indicating inefficient operation with long cycle times. Comparisons of SIDRA estimates of delay, back of queue and queue clearance time for actuated signals with those predicted by microsimulation as well as those observed at a real-life intersection are presented.
The University of Pisa researchers studied a1.5 km roadcorridor with seven intersections including signals, roundabouts and two-way stop controlled intersections.SIDRA NETWORK model was used to analyze two scenarios. The researchers concluded:
“This study has been possible thanks to SIDRA INTERSECTION (NETWORK version) that showed its capability of modelling both single intersections and the road corridor.”
NICOLI, F., PRATELLI, A. and AKÇELIK, R.(2015) Improvement of the West road corridor for accessing to the New Hospital of Lucca (Italy). Presentation at the 21stInternational Conference of Urban transport and the Environment (URBANTRANSPORT 2015), Valencia, Spain, Jun 2015.
This paper presents results ofthe study of a road corridor in the historical city of Lucca, Tuscany,Italy. The corridor is about 1.5 km with seven different intersectionsalong the corridor, including signalised and two-way stop controlledintersections and roundabouts. SIDRA INTERSECTION network model was usedto analyze two scenarious; namely, the "Present situation" and the"Design situation" to verify the effectiveness of some proposedintersection improvements. The network model results strongly supportedthe design proposal of improving the West corridor for accessing the newhospital of Lucca. The analyses showed that significant improvementscould be made to traffic performance in the road corridor in general,including environmental benefits in terms of reduced fuel consumptionand emissions.
North Carolina State University carried out a comprehensive study and evaluation of alternative software packages for signalised intersections (SIDRA, TRANSYT, HCS/HCM, Signal 94, HCM/Cinema, EVIPAS) for the North Carolina Department of Transportation. The report stated: “SIDRA’s powerful combination of high model usability, superior matching of field delays at the lane group level, versatile optimization features, and graphical user interface makes it the model of choice from this study. ”.
SIDRA was rated best on all accounts and recommended for use as the standard model.
Average ratings were as shown in the table below.
|Model usability||SIDRA: 4.1/5||TRANSYT 7F: 3.3/5||HCM/HCS: 3.2/5|
|Quality of signal optimisation||SIDRA: 4.0/5||TRANSYT 7F: 2.0/5||HCM/HCS: 3.0/5|
|Delay model evaluation||SIDRA: 4.5/5||TRANSYT 7F: 4.0/5||HCS/HCM: 3.0/5|
Field Assessment of the Performance of Computer-Based Signal Timing Models at Individual Intersections in North Carolina. Report for the North Carolina Department of Transportation. Center for Transportation Engineering Studies, Department of Civil Engineering, North Carolina State University.
North Carolina State University carried out a comprehensive study and evaluation of alternative software packages for signalised intersections (SIDRA, TRANSYT, HCS/HCM, Signal 94, HCM/Cinema, EVIPAS) for the North Carolina Department of Transportation. SIDRA was rated best on all accounts (model usability , quality of signal optimization and delay model evaluation) and recommended for use as the standard model. The report concluded: “SIDRA’s powerful combination of high model usability, superior matching of field delays at the lane group level, versatile optimization features, and graphical user interface makes it the model of choice from this study.”.
Using SIDRA INTERSECTION, Vic Roads engineers redesigned a highly congested two-lane roundabout in Melbourne as a three-lane roundabout (shown below) eliminating persistent congestion.Detailed field surveys were carried out before and after the reconstruction.
Three-laning a two-lane roundabout - the outcomes. paper by O'BRIEN, A., AKÇELIK, R., WILLIAMSON, D. and PANTAS, T. Compendium of Technical Papers (CD). 67th Annual Meeting of the Institution of Transportation Engineers, Boston, USA, (1997).
Using SIDRA INTERSECTION, VicRoads engineers redesigned a highly congested two-lane roundabout in Melbourne, Australia as a three-lane roundabout eliminating persistent congestion. Detailed field surveys were conducted before and after the reconstruction. This article presents detailed information about this study.
Case studies undertaken by ARRB Group Ltd under AUSTROADS project NS 1371 (Guidelines for Selecting Techniques for the Modelling and Analysis of Network Operations) included comparison of the performance of micro-analytical (SIDRA INTERSECTION) and microsimulation (VISSIM) modelling of this intersection including comparison against field measurements.
The study found that
“Cycle average queue estimates of the two models were within one vehicle of field measurement” and suggested that "Resources (i.e. labour and software) used to develop and run SIDRA models were substantially less" compared to the resources allocated for developing and running microsimulation models. It was estimated that microsimulation required three to five times more resources than SIDRA.
Guidelines for selecting techniques for the modelling of road network operations. 24th ARRB Conference, Melbourne, Australia.
This paper describes guidelines for the selection of the appropriate modelling techniques for the analysis of road network operation schemes. The quidelines include a worksheet that faciliates in the assessment of four major categories of modelling techniques based on a scoring system. The guideliines were further refined for application to single intersection analysis through a case study. SIDRA and microsimulation models, including fixed time, vehicle-actuated and SCATSIM models were compared based on field data. The viability of manual calculation techniques was also examined. Based on the findings, a hierarchy of modelling techniques was recommended.
A study comparing field-measured delays at single-lane roundabouts in the USA with those predicted by SIDRA INTERSECTION concluded that SIDRA INTERSECTION can accurately predict delay for American single-lane roundabouts.
Flannery, A., Elefteriadou, L., Koza, P. and McFadden, J. (1998).Safety, delay, and capacity of single-lane roundabouts in the United States.Transportation Research Record 1646, pp 63-70.
A study of field-measured delays at single-lane roundabouts in the USA with those predicted by SIDRA concluded that "SIDRA can accurately predict delay for American single-lane roundabouts".
See here for other technical articles reporting use of SIDRA INTERSECTION for roundabouts.
The travel time function used in SIDRA INTERSECTION for uninterrupted movements was found to be very accurate for US conditions.
Dowling, R.G., SINGH, R. and Cheng, W.W.K. (1998).The accuracy and performance of improved speed-flow curves. Technical Note.Road and Transport Research 7 (2), pp 36-51.
Read more related articles on speed-flow functions.
Through actual measurement of vehicle fuel consumption, this study found that the fuel consumption model which is the basis of the SIDRA INTERSECTION model is very accurate.
TAYLOR, M.P. and YOUNG, T. (1996). Developing a set of fuel consumption and emissions models for use in traffic network modelling. Proceedings of the 13th International Symp. on Transportation and Traffic Theory. (Ed. J-B. Lesort). Pergamon, Elsevier Science, Oxford 1996, pp 289-314.
Read more information on this topic.