Cumulative curve method for calculating saturation flow rate and phase lost time

Compared with Webster method, cumulative curve method can measure starting time and ending time. As an example, this method was applied in several lanes in Changchun city. The applying results show that the saturation flow rate of one lane is between 1 600~1 900 veh/ h, and the total lost time is less than 2 s without disturbing. The saturation flow rate approxi- mates the assumptive value, 1 700~1 800 veh/h, but the lost time is less than what HCM com- mends, 3~5 s, which is also less than the yellow time, 3 s.