The Modeling And Simulation Research On Traffic Capacity Of Highways Under The Effect Of Speed Dispersion

Transportation, the important material base for human development for all along, isdeveloping rapidly as the quick development of the country. Highways, which arefoundation stones of transportation area, need considerable investment in construction.Because highway capacity is the main decision base for the scale of the construction ofhighway infrastructure, it is especially important to research on the highway traffic capacitysystematically, fully, and reasonably.This paper summarized the influence sources of the characteristics of highway trafficflow from macro perspective by analyzing the main influence factors on traffic capacity andtheir function characters, based on the specialty of the operation of highway systems inChina. It analyzed the interferences and interaction relations among key factors. This paperelaborated the mechanism of the speed dispersion, which is a key factor. This paper alsointroduced the development of basic models for traffic capacity, and analyzed thecharacteristics of the changes in models. The specialty of the analysis of the traffic capacityof highways in China was presented in the paper. The traffic capacity models for basicsections of highways, including a model for roads and a model for cars, were built based oncellular automation model. Combined with operation patterns of vehicles on highways inChina, the developing rules were distributed to models to research on the traffic operationpatterns and developing rules under different vehicle types and different rules of lanes. TheMatlab program was applied to simulate the models. By changing the inputs, it analyzed theresult of the speed dispersion under operation and the interaction relationship between thespeed dispersion and the changing of lanes. The paper finally concluded the actual trafficcapacity of highways under different limiting conditions.The research result of the paper will help to systematize the analysis of highway trafficcapacity, which will make highway traffic capacity more accord with the present conditionin the country. These results have certain practical significance to satisfy the demand ofhighway management and the long-term and immediate-tern planning and constructionwork.