The Calculation Method Research Of Urban Road Network Carrying Capacity Considering The Effective Utilization Of Time-space Resources

Urban road network carrying capacity is a kind of inherent attribute of the road network, it affects the traffic operation status of road network, determines the ability to accommodate the traffic volume on different traffic conditions, it is the decision index of scheme planning and reconstruction, and is the theoretical basis of network facilities planning, design and management.Firstly, in view of above-mentioned, this paper analysis the theoretical system of the urban road network carrying capacity, Time-space consumption method and capacity method, this paper illustrates the models, algorithm and the advantages and disadvantages of every method, and final determines the basic theory, the two-dimensional model of Time-space consumption method.Secondly, based on the former research, we analysis the effective utilization of time-space resources on road network and the traffic, redefining the urban road network carrying capacity, witch is the standard vehicle nuber that the traffic system can carry in the peak period, in a certain traffic operation state, considering the effective utilization of Time-space resources, and ensuring that urban road network system to maintain the sustainable development state.Then, based on the basic theory and the definition of the urban road network carrying capacity, the parameters we need to determine are the effective length and time of Time-space resources, and the time-space resources that traffic individual occupies once, and the lateral interference coefficient. These parameters of original time-space consumption method need to be investigated and to be calibrated, witch makes the method lack of accuracy and dynamic, so the fine calculation of these parameters is the focus the innovation of the this paper. Through the study on the running trajectory in the intersection, we use traffic flow wave theory and M/M/1 queuing theory to study the effective length of the time-space resources, analysis the arrival rate and the leaving rate to study the effective time of the time-space resources, modify lateral disturbance coefficient through drawing lessons from Shanghai, study the space headway through car-following theory, and calculate the average time for a trip using TransCAD, finally, we establish the scientific, accurate, practical model of urban road network carrying capacity.At the end of this paper, we make the example application and verification through the road network of a certain city core zone, and then we contrast and analysis the two different result calculated by original method and this paper’s method, illustrating the accuracy and practicability of this paper’s model.