关键词: 交通工程；城市交通；路网优化；交通微循环；路网；双层规划

Abstract: In order to solve the problem of traffic congestion of arterial roads and low utilization rate of branch roads, a two-layer optimization model of traffic microcirculation network considering intersection delay was established by using the traffic microcirculation theory and considering the impact of intersections on the total delay of the road network. Under the constraints of road saturation, traffic capacity and investment amount, the upper model determined the roads constituting the traffic microcirculation network, and determined the reconstruction degree of the selected roads, so as to maximize the average travel speed of the road network in the planning area. The lower-layer model established the function minimizing the total impedance of the road network to assign OD traffic on the premise of meeting the requirements of upper-layer model, through combining the intersection delay with the travel time of the road section. And a solving algorithm for the model was established by genetic algorithm. Finally, taking the road network in the NEW-MART area in Daqing city as the research object, and a case study was carried out. The research results show that the average saturation of the arterial road is reduced from 0.72 to 0.65 and the average saturation of the road network is reduced from 0.65 to 0.43 after optimizing the traffic microcirculation road network. The proposed method can maximize the operation benefits of the road network within the scope of the investment quota.

Key words: transportation engineering; urban traffic; road network optimization; traffic microcirculation; road network; bi-level programming model