Applicability of Coordinated Signal Control Strategies for Urban Traffic in High Saturation

Simultaneous system and progressive system are two classic control systems in transportation .The tradi-tional progressive systems currently used in China are not sufficient to deal with high-saturation traffic flows .Further-more ,it even worsens the complex traffic conditions by inappropriate control strategies .For traffic states in high satura-tion ,the reason why progressive system doesn't work is analyzed ,and the simultaneous system as the signal control strat-egy is proposed .Based on the theory analysis ,effects of these two signal control strategies are compared in different satu-rations with Vissim simulation .The conclusion is drawn and proved with certain cases .