Cell transmission model based traffic signal timing in oversaturated conditions
来源期刊:中南大学学报(英文版)2013年第4期
论文作者:WANG Ping(王屏) L. S. Jones YANG Qun(杨群) S. Gurupackiam
文章页码:1129 - 1136
Key words:oversaturated flow; conditional cell transmission model; traffic signal timing; spillback; blockage
Abstract: in order to investigate enhancements to cell transmission model (CTM) as a tool for traffic signal timing in oversaturated conditions, randomly distributed saturation flow rates and arrival rates were used instead of constant values to simulate traffic flow movement, estimate the average delay of the network and search for an optimal traffic signal timing plan. A case study was given to demonstrate that the proposed methodology can capture unique phenomena in oversaturated conditions such as forward wave, spillback and lane entrance blockage. The results show that CTM underestimates travel time by 25% when compared to Simtraffic, while the enhanced CTM underestimates by only 3%. A second case study shows that a dynamic signal timing plan is superior to a fixed signal timing plan in the term of average delay.
WANG Ping(王屏)1, L. S. Jones2, YANG Qun(杨群)1, S. Gurupackiam2
(1. Key Laboratory of Road and Traffic Engineering of Ministry of Education
(Tongji University), Shanghai 201804, China;
2. Department of Civil, Construction, and Environmental Engineering, the University of Alabama,
Tuscaloosa, AL 35401, USA)
Abstract:in order to investigate enhancements to cell transmission model (CTM) as a tool for traffic signal timing in oversaturated conditions, randomly distributed saturation flow rates and arrival rates were used instead of constant values to simulate traffic flow movement, estimate the average delay of the network and search for an optimal traffic signal timing plan. A case study was given to demonstrate that the proposed methodology can capture unique phenomena in oversaturated conditions such as forward wave, spillback and lane entrance blockage. The results show that CTM underestimates travel time by 25% when compared to Simtraffic, while the enhanced CTM underestimates by only 3%. A second case study shows that a dynamic signal timing plan is superior to a fixed signal timing plan in the term of average delay.
Key words:oversaturated flow; conditional cell transmission model; traffic signal timing; spillback; blockage