Research On Signal Control Method Of Nontypical Deformity Intersection

Intersection is key factor restraining urban road network operating level. Deformity intersection can be classified into two types, i.e. regular and irregular deformity intersection. Although the number of irregular deformity intersection is not much, these deformity intersection often become not congested points and black points of urban road network, but the emphasis and difficulty of road traffic management and control for the reasons of complex surrounding, staggered alignment, trffic conflicts and their interlaced direction and so on. So the traffic control method of irregular deformity intersection study are studied in this paper.Based on comprehensive investigation of urban road intersection, the connotation of deformity intersection is defined. Deformity intersections are classified into two types, i.e. typical and nontypical deformity intersection. The irregular deformity intersections are defined as nontypical deformity intersection, and nontypical deformity intersections are classified as three types, i.e. single point type, the group type and roundabout whit five or more than five roads.Five types in some cities were investigated. The parameters of geomitric alignment and traffic operating were analyzed. The quantitive impacts of geometric alignment parameters (including cross angle, turning radius) on driving speed, traffic delay and queue length were conducted and corresponding relation models were established.For the traffic control problems of nontypical deformity intersection, conflict must be isolated. Based on the relationship between intersection angle and driving speed, the principal of phase composition of each direction was optimaized. The general method and procedure of traffic signal control was proposed for nontypicla deformity intersection based on the judgement of traffic conflict seerious degree. The coordinated optimization control method of the A group type of deformity intersection was given based on the optimal principals of road network and phase difference.Finally, a single point type (K type), a group type of nontypical deformity intersection and a roundabout with multi-roasd were selects as example, and application analysis was conducted for proposed traffic control method in this paper. The examples shows that proposed method is reasonable and feasible.