Effect of Trotros on Saturation Flow at Selected Signalized Intersections on the 24 th February Road, Kumasi, Ghana

Trotros constitute a good proportion of urban traffic on the 24 th February Road. The effect of the Trotros on saturation flow at signalized intersections could therefore be substantial. This research studies and analyses the effect of Trotros on the saturation flow at selected signalised intersections by collecting data along the route. A strong correlation was observed between the measured saturation flow using the headway method and the proportion of Trotros stopping per hour suggesting that their presence indeed impact on the capacity significantly and should therefore be considered in the capacity analysis of signalized intersections. The effect of Trotros on saturation flow rate was incorporated in the Highway Capacity Manual (HCM) model by comparing the field saturation flow to the adjusted saturation flow using the HCM model. Results show that saturation flow measured using the modified HCM equation is generally closer to observed saturation flow values.