The Analysis Method of Capacity and Delay on Entrance Lane with Road-side Bus Lane

In order to reveal the traffic characteristics at signalized intersections with road-side bus lane, the analysis methods of capacity and delay at entrance lane were studied. Selecting a signalized intersection with road-side bus lane as investigation location, several traffic parameters were surveyed. Considering the traffic conflict between right-turn vehicles and through buses in this kind of entrance lane and based on the Gap Acceptance Theory, the calculation model of saturation flow rate, which is a key parameter both in the formulas of capacity and delay at signalized intersection mentioned in HCM2000, was improved. Using the investigation data, the calculation results of the traditional model and improved model were compared and analyzed. The research indicated that, comparing with common entrance lane, the capacity of right-turn lane at the entrance lane with bus lane should be reduced, and the travelling delay of bus lane and its inside adjacent lane should be increased. The degree of these effects is related to bus volume, right-turn volume and headway between buses.