Research On Traffic Operation Scheme Based On Road Diet Strategy

The two-way four-lane road,as the arterial road of small and medium-sized cities,needs to undertake more transportation functions,not only to meet the requirements of mobility,but also to take into account the accessibility.Both sides of the two-way four-lane road are often covered with institutions,commerce,hospitals,schools,and residences.The population density is large.Frequent vehicle entry and exit at the entrance has a great impact on the main road driving order.For such roads,the commonly used traffic operation method is to add middle traffic guardrail to standardize the driving order,but it will result in vehicles that should turn left at each entrance have to go straight to the front intersection and concentrate their U-turn,thereby increasing the delay at the intersection and travel time of the vehicle at the entrance.In recent years,the international approach of road diet is an advanced strategy to solve this problem.It is a comprehensive optimization strategy for existing road space resources.It can improve the traffic safety level and effectively improve the traffic environment of non-motorized lanes without significantly reducing the traffic efficiency.The usual form of road diet is to convert a two-way four-lane road into a two-way three-lane road with a two-way left-turn lane(TWLTL),but twoway left-turn lane is not included in our national standards and cannot be directly applied in China.Therefore,we need to draw on the strategy of road diet and design a three-lane scheme that is in line with the actual road traffic in China.In this study,a three-lane scheme was designed based on the strategy of road diet.The road segment is a two-way two-lane road with a central area of a certain width in the middle.A left-turning lane is set at the entrance by compressing the central area.Through theoretical analysis,the three-lane scheme can reduce the number of conflict points and balance the right of way of various types of traffic,but it may also lead to illegal overtaking and traffic congestion.In addition,the traffic volume of the main road,the left-turn traffic volume of the main road,and the traffic volume,spacing,number,distribution form of the entrance may all affect the implementation effect of the three-lane scheme.In order to evaluate the operation effect,this study applied the three-lane scheme in practice and designed a control experiment.Taking the section of Xinghai North Street Shoushan Road to Longxing Road as the experimental section,implement the three-lane scheme;take the section of Xinghai North Street Chuanbei Road to Wenquan East Road as the control section,keeping the original two-way four-lane scheme unchanged.From the subjective feelings of motor vehicle drivers,non-motor vehicle drivers and pedestrians,traffic operation,traffic safety,etc.,comprehensively evaluate the implementation effect of the three-lane scheme.The results show that the three-lane scheme can significantly reduce the speed of motor vehicles,reduce the speed difference between vehicles,improve the level of traffic safety,and improve the environment for non-motor vehicles and pedestrians.In order to study the applicability of the three-lane scheme,this study used VISSIM simulation software to build a three-lane model and a four-lane model to study the influence of the combination of different variables on the simulation results,including the traffic volume of the main road,the left-turn traffic volume of the main road,and the traffic volume,spacing,number,distribution form of the entrance.Grey correlation analysis is used to determine the degree of influence of each variable on the simulation results,and by setting the target conditions,the main road traffic range applicable to the three-lane scheme is screened.The results show that the main road traffic volume has the greatest correlation with the simulation results;if the one-way main road traffic volume is less than 1000veh/h,the three-lane scheme can be recommended.