Study of traffic delay at signalised junction

• Main Author: Boddu, Shruti Shree.
• Other Authors: Wong Yiik Diew
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Civil engineering::Transportation
• Online Access: http://hdl.handle.net/10356/53853
• Institution: Nanyang Technological University

Traffic delay is the additional traffic time experienced by a vehicle due to various circumstances that impede the desirable movement of vehicles. It is measured as the difference between the actual travel time and the free-flow travel time. Traffic delay can occur at signalised junctions due to the signal timings. Hence, to minimise traffic delay, signal timings can be adjusted according to the specific needs of a junction. However, the first step to this is to accurately calculate the traffic delay at that junction. This purpose of this research project is to obtain a method that accurately calculates traffic delay under the local traffic conditions. The existing traffic delay formulas do not give an accurate representation of traffic delay under the local conditions. Additionally, they do not take vehicle types into consideration while calculating the delay. This project aims at taking these factors into consideration. For this project, traffic flow is studied at four signalised junctions in Singapore. Data is collected in order to calculate the observed traffic delay as well as the traffic delay using existing formulas. Subsequently, an attempt is made at modifying these formulas to suit local needs. Additionally, the junctions are simulated on the micro-simulation software VISSIM, to obtain an additional value of traffic delay, to better facilitate the comparisons and calculations. It was found that the observed traffic delay had a substantial variation from the traffic delay calculated using existing traffic delay formulas. Traffic delay calculated for different vehicle types using these formulas yielded the same answer, while the observed traffic delay was different for different vehicle types. The traffic delay obtained using VISSIM was closer to the observed values, while the traffic delay obtained using the modified model was the closest to the observed values.