01660329

Component

Freight deliveries on signalized urban streets are known to cause lane blockages during deliveries. When delivery vehicles block lanes of traffic near signalized intersections, the capacity of the intersection is affected. Current practice is for traffic signals to be timed assuming that each approach can serve vehicles at the unobstructed saturation flow. The goal of this research is twofold: 1) to develop models to quantify the capacity and delay effects of a lane blocking freight delivery on a signalized urban street, and 2) to develop a model for adapting the traffic signal timing in real time for signal cycles during which a delivery blocks a link upstream of the intersection. The results of the queueing model show that accounting for the dynamics of queuing provides closed form analytical formulas for delay and capacity that can account for varying locations of deliveries and different impacts on different lane groups. The signal control algorithm requires real-time information about the location of the double-parked delivery vehicle, which is assumed to be available from connected vehicle data from urban freight vehicles or from another detection system. The results show that for low levels of traffic demand, the signal control method reduces intersection delay compared to a signal that is timed for unblocked traffic. The algorithm also keeps the intersection approach undersaturated for higher levels of demand, which is important because deliveries can last for many signal cycles.

This paper was sponsored by TRB committee AHB25 Standing Committee on Traffic Signal Systems.

18-05141

English

8p

2018

Transportation Research Board 97th Annual Meeting

Digital/other

Figures; References; Tables

Arterial highways; Evaluation; Freight transportation; Optimization; Real time control; Signalization

Freight Transportation; Highways; Operations and Traffic Management

Transportation Research Board Annual Meeting 2018 Paper #18-05141

TRIS, TRB, ATRI

Jan 8 2018 11:17AM