ISSN: 1813-0410

Author : A. Ewadh, Hussein

Traffic Conflict Technique to Predict Countermeasure Effectiveness at 3-legs Signalized Intersections

Hussein A. Ewadh

journal of kerbala university, 2008, Volume 4, Issue 1, Pages 9-15

Traffic accident reduction is a measure to evaluate the effectiveness of any proposed countermeasure. A draw back of estimating this reduction is that, traffic accidents involve; rare occurrence, under-reporting, unreliability, and difficult observation. This paper aims at estimating the effectiveness of countermeasures using traffic conflict technique (T.C.T) as alternative.
This paper involves a study of the traffic operations and safety analysis for a sample of three legs signalized intersections in Baghdad City. Traffic and conflict data are collected through observation of the selected sites. Regression analyses are performed to relate hourly traffic conflict and average stopped delay. Some countermeasures of traffic control and geometric design are adopted. Analysis of traffic operation before and after countermeasure is implemented using HCS software.
A developed statistical model indicates that 92.5 % of variation in hourly traffic conflict can be predicted significantly by average stopped delay. A countermeasure can be evaluated due to before and after average stopped delay based on HCS output and accordingly the involved conflicts based on the developed statistical model. The results show that, more than 35 % of potential conflicts can be reduced due to countermeasures and the highest reduction (62.6 %) is introduced due to increase of lane width. This paper maximizes the usefulness of T.C.T as a tool to predict the effectiveness of any proposed countermeasure before its implementation.