Signal design for displaced left-turn intersection using Monte Carlo method

Abstract

Unconventional intersection designs have been receiving increased consideration at intersections that serve high traffic demands. Although operational performance of unconventional intersections has been evaluated in a number of studies, little research has been conducted regarding methodologies to obtain optimal signal timings for them. Several studies have reported that commercial signal timing packages have not been able to be utilized to develop optimal signal timings due to the unique design features of the unconventional intersections. In this paper a Monte Carlo simulation method to minimize intersection delay is described as well as a bandwidth maximization method for a Displaced Left-Turn (DLT) intersection, one of the most popular unconventional intersections. The proposed method is applied to a representative intersection design for two different traffic demand scenarios. It is seen that the two optimization approaches may result in different optimal solutions and the Monte Carlo simulation is able to provide near-optimum parameter selection ranges for the given traffic demands. Also, it is found that the Monte Carlo method is sufficiently flexible to provide intersection-tailored solutions with intersection specific design parameters.