Calculation And Analysis Of Urban Road Capacity Under Rainfall Condition

With the development of China's cities and the rapid increase in car ownership,traffic demand is growing,the road network pressure is getting worse.Rainfall has a wider impact on traffic,especially on urban traffic.traffic congestion,traffic delays,and urban residents' travels are affected.Studying the traffic capacity of urban road sections under rainfall conditions can provide the basis for ensuring the reliability of the future road network in rainfall weather and the reliability of taking risks.This paper first summarizes the research results of the impact of rainfall on urban traffic at home and abroad,and lays a theoretical foundation for the paper.On the basis of literature review at home and abroad,this paper analyzes the influencing factors of urban roads and the calculation of traffic capacity from the analysis of traffic flow characteristics of different sections of rainfall.Determining the influencing factors were the three aspects of rainfall intensity,visibility and lane width.Secondly,the influencing factors of rainfall under the traffic condition are calibrated,and the relationship between the rainfall condition and the vehicle speed is established by analyzing the driving behavior of the rainfall intensity and visibility.The driving behavior influence characteristic considering the influencing factors of rainfall is modeled.According to the model,the change of urban road speed under rainfall condition is calculated.According to the different rainfall velocity distribution characteristics and velocity calculation model,combined with the rainfall behavior under the driving behavior analysis.Establishing the car-following model under rainfall conditions.Building simulation scenarios of the car-following model under rainfall conditions.Simulating and analyzing the urban road capacity under rainfall condition.Calculateing the actual capacity of urban road sections under different circumstances.Analyzing the influence of rainfall condition on road capacity,and the actual traffic capacity under rainfall condition is finally obtained.determining the influence level of rainfall.Finally,Combining the influence factors of road capacity and influence grade.Verifying by an example.UC-winRoad is used to simulate road driving,and the accuracy of the coefficients is determined.A dynamic weather speed limit method based on capacity influence is formulated.To provide basis for the mitigation of urban road congestion and traffic safety in rainy days.