Modelling critical gaps for U-turn vehicles at median openings under Indian mixed traffic conditions

Abstract

Establishment of un-signalized median openings have expanded in numerous urban districts of cities in India. The thought process behind this establishment is to take out issues connected with illicit U-turns occurring at crossing points and other transportation facilities near these median openings on multi-lane urban streets. Gap Acceptance concept of U-turn drivers is an imperative angle at un-signalized median openings for deciding limit of accidents. Critical Gap structures the sole parameter in Gap acceptance models for assessing U-turns at median openings. Estimation of critical gaps for U-turn vehicles at median openings under mixed traffic conditions have not been addressed until today. The explanation for this carelessness is the complex vehicular associations and dangerous path changing operations by non-motorized vehicles at these facilities. So as to take care of this issue and to address the blended/ mixed traffic conditions in India critical gaps were assessed utilizing a few Gap acceptance models with a point of evaluating limit of these U-turns at median openings. Information gathered for this study is in the form of video-image processing/recording of nine bi-directional-mid-block median openings on 4-lane and 6-lane roads without left-turn lanes placed in the urban areas of Bhubaneswar and Rourkela located in the eastern part of India.ANOVA regression modelling is done in IBM –SPSS which resulted in predicting power variation of merging time with accepted gaps for both male and female 2 Wheeler drivers."). The principal piece of this study focuses on the estimation of the critical gaps while the second part draws our attention towards various models relating variables like accepted gaps and critical gaps with other traffic characteristics like through/conflicting traffic flow and speed, driver’s waiting