Research On The Traffic Organization Mode Of Diamond Interchange Secondary Road And The Technical Index Of Double Crossover Intersection

The level of urban motorization in China is rising rapidly,and the number of motor vehicles is increasing continuously.However,there is a huge contradiction between the increasing traffic demand of residents and the level of urban traffic service at this stage.The diamond interchange has the advantages of large capacity,low cost and small land occupation.However,the traffic flow of the secondary road intersection is complex,accidents occur frequently and congestion is serious,which affect the road capacity.Setting up double crossover intersection on secondary road of diamond interchange is an effective method to improve the above problems,and can ensure the safe and smooth running of vehicles.First of all,on the basis of analyzing the characteristics of the intersection traffic organization,the paper expounds the single-point diamond interchange,double roundabout interchange,Milwaukee design interchange and diverging diamond interchange,four kinds of diamond interchange secondary road traffic organization form and characteristics;and summarizes the applicability of each organization mode.Furthermore,the traffic organization characteristics of double crossover intersection are studied in depth.Secondly,the influencing factors of crossover design and layout forms are analyzed.Combined with the lane changing trajectory of vehicle model,the opposite lane changing distance on crossover was put forward.based on the traffic flow theory and queuing theory,the calculation model of the crossover spacing is established,and values are given.The lane width,widening value and the median width in the intersection area are studied.Finally,according to the characteristics of traffic flow at double crossover intersection,the signal phase design scheme is proposed through traffic flow combination,and the signal timing parameter calculation method is given.The offset optimization model was established by MAXBAND,and the optimization model of crossover spacing is established according to the traffic flow theory.VISSIM simulation experiment is used to verify the advantages of double crossover intersection.