Optimization model for bus priority control considering carbon emissions under non-bus lane conditions

Green extension and red truncation strategies were examined to study the influence of bus priority control strategies on traffic carbon emissions under non-bus lane conditions. Considering the main influencing factors, such as the delay and parking times, a bus speed probability density function based on the fluctuation characteristics of the vehicle speed in the intersection control area was introduced. A bus priority control optimization model was developed for non-bus lane conditions to optimize the carbon emission reductions of buses and social vehicles with different fuel types under different working conditions, and the Frank–Wolfe algorithm was used to solve the model. According to the model, when bus signal priority control was adopted under a green extension strategy, the carbon emission reductions were optimal (24.38%) when the green extension was 6 s. Under a red truncation strategy, the carbon emission reductions were optimal (26.01%) when the red truncation was 5 s. These results suggest ways in which carbon emissions in the intersection control area can be reduced to achieve the optimal overall traffic benefit for the intersection.