Volume List  / Volume 10 (4)



DOI: 10.7708/ijtte.2020.10(4).05

10 / 4 / 456-467 Pages


Aparna Vimal Kumar - Department of Civil Engineering, College of Engineering Trivandrum, Thiruvananthapuram, Kerala, India -

Salini Sasikumar - Department of Civil Engineering, College of Engineering Trivandrum, Thiruvananthapuram, Kerala, India -


U-turning movements impart a significant effect on traffic characteritics at the medians.This paper attempts to study critical gap of U-turns at unsignalized median openings. Mixed traffic conditions in India makes critical gap estimation more tedious task. Critical gap at median openings was estimated using traditional method, modified Raff method and merging behaviour approach. The merging behaviour approach was found to be more suitable under heterogeneous conditions. The estimation of critical gap by merging behaviour approach is done based on the merging time of U-turning vehicles. A model was developed for predicting critical gap considering all vehicle types. From the analysis the critical gap was found to depend on accepted gap and merging time.

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