A review of critical gap estimation approaches at uncontrolled intersection in case of heterogeneous traffic conditions

Abstract

Keywords: critical gap gap acceptance uncontrolled intersection mixed traffic clearing behaviorThe gap acceptance study is an indispensable study in the determination of capacity and delay of the individual moment at uncontrolled intersection and critical gap is one of the chief parameter allied with this study. Most of the studies related to critical gap estimation have been carried out in developed countries where traffic is homogeneous and rules of priorities as well as lane disciplines are voluntarily followed. However, in India, priority rules are less honored which consequently create more clashes on intersections and modelling of such behavior becomes complex. Even though very limited studies have been reported in such case. This paper presents the study of gap acceptance behavior of drivers on an uncontrolled intersection. In order to examine the gap acceptance behavior of drivers, 4-legged uncontrolled intersection located in a semi-urban area of Ahmedabad in the state of Gujarat was selected. Video recording technique was adopted for collection and analysis of the data. Different existing methods are used to calculate the critical gap for through and right turning movements from the minor road. Gaps are analyzed for three different vehicle types. A comparison between different existing methods of critical gap determination is carried out and their critical analysis is presented. The result shows, except clearing behavior approach, all other methods are failing to represent the actual scenario of the critical gap under mixed traffic conditions as these all methods had been developed for homogeneous traffic conditions.

Gap acceptance behavior of drivers at uncontrolled T-intersections under mixed traffic conditions

“…The results suggest that the clearing behavior approach gives higher values of critical gap than the logit method if the aggressive behavior is not taken into consideration. This observation is consistent with the studies under mixed traffic conditions [5,15]. However, incorporating aggressive behavior helps to visualize the actual scenario because the critical gaps can be obtained for aggressive and nonaggressive drivers separately.…”

“…Amin and Maurya [15] calculated the critical gap using logit model along with others methods and compared them. Sangole et al [16] used an adaptive neuro-fuzzy interface system (ANFIS) approach to model the gap acceptance behavior of two-wheelers at uncontrolled intersections.…”

“…Clearing behavior approach has proven to give satisfactory results in mixed traffic conditions so far [5,15]. The clearing time curve (1-F ct , where F ct is the cumulative frequency distribution curve for clearing time) and the corresponding gap acceptance cumulative frequency curve (F a ) intersect at a point which indicates a situation when clearing time is just equal to the gap accepted.…”

RETRACTED: <i>Estimation of Critical Gap of U-Turns Road in Turkey</i>

“…The main advantage of this method is, it provides a true average of the critical headway, and it does not need any predefined distribution function of critical gap and assumptions related to the consistency and homogeneity of drivers whereas MLM needed predefined distribution function as well as these assumptions [16]. Wu explained the method as described below.…”

A method to estimate the capacity of an intersection of waterways in ports

“…Though a method to estimate the capacity of waterway intersections does not exist, the concept of estimating intersection capacity has been extensively studied for road traffic. Previous research on unsignalised road intersections presented two methods to estimate capacity: the gap-acceptance theory (among others, Brilon, Koening, and Troutbeck 1999;Amin and Maurya 2015), and the conflict technique (Brilon and Miltner 2005).…”