A NEW MODEL FOR ESTIMATING CRITICAL GAP AND ITS DISTRIBUTION AT UNSIGNALIZED INTERSECTIONS BASED ON THE EQUILIBRIUM OF PROBABILITIES

This paper presents a new model for estimation critical gaps at unsignalized intersection. The theoretical background of the new model is the probability equilibrium between the rejected and accepted gaps. The equilibrium is established macroscopically using the cumulative distribution of the rejected and accepted gaps. The model yields directly the probability distribution function of the critical gaps. The new model has the following positive properties: a) solid theoretical background (equilibrium of probabilities), b) robust results, c) independent of any model assumptions, d) possibility of taking into account all relevant gaps (not only the maximum rejected gaps as is the case of the Troutbeck model (1992)), e) possibility of achieving the empirical probability distribution function of the critical gaps directly, and f) simple calculation procedure without iteration. The implementation the new model is simple and robust. It can be carried out using spreadsheet programs (e.g. EXCEL, QuatroPro etc.). Thus, with the new model a useful and promising tool can be set up for professionals in traffic engineering