Simulation Research On Capacity Of Underground Intersection Connections Based On VISSIM

The construction of urban underground traffic has increasingly become the focus of urban development.In the face of increasingly scarce ground road resources,more and more urban management constructors have turned their attention to the development of urban underground road resources.In the planning and construction of underground roads,traffic capacity has important planning and guiding significance for road design,traffic management,etc.However,at present,there is relatively little research on the capacity of underground roads in China,and basically the capacity of the roads on the ground is still used.model.The bottleneck of underground transportation capacity is often concentrated at the junction with the ramp.Therefore,it is necessary to combine the traffic flow characteristics of underground roads to study the capacity of the underground ramp section to provide reference for engineering practice.In this thesis,the following contents are studied for the capacity of the underground interchange ramp:(1)Analyze and summarize the driving conditions and traffic characteristics of the underground interchange,and make a reasonable analysis of the driving characteristics of the driver under the underground traffic conditions;(2)Analyze and summarize the characteristics of the traffic flow in the connecting section of the ramp,including the characteristics of traffic flow in the connecting section of the inlet ramp,the connecting section of the outlet ramp,and the bottleneck section;(3)Based on the existing capacity calculation method,combined with the characteristics of traffic flow in the junction section of the underground interchange ramp,a revised calculation method for the capacity of the ramp section is proposed;(4)Through VISSIM simulation software,determine the traffic flow form,number of lanes,and traffic flow ratio correction coefficient in the calculation model of the capacity of the underground interchange ramp,and verify the model of the calculated capacity of the connected section of the underground overpass ramp to obtain the model.The accuracy of the calculation;(5)For the case of the second subsea tunnel in Jiaozhou Bay of Qingdao,apply the calculated capacity calculation model of the connecting section of the ramp to calculate the capacity of the ramp section of the case,and combine the simulation analysis of the case with VISSIM to analyze and evaluate the service level of the case.