Research On Applicability Evaluation And Optimization Of Mountainous City Bus Dedicated Lanes

Prioritizing the development of public transportation is an effective way to solve the contradiction between supply and demand of urban transportation and adjust the transportation structure.The establishment of bus lanes is one of the most direct and effective measures to develop a bus priority policy.When major cities have set up bus lanes,mountain cities are more complicated than plain cities due to their special topographic features,such as limited land resources and tight road resources.This article evaluates the applicability of the built bus lanes in Chongqing,and explores the effects of its layout.This dissertation firstly studies and analyzes the layout mode of bus lanes in mountainous cities.Starting from the topographic and transportation characteristics of mountainous cities,the unique urban form,spatial layout,transportation composition,and residents’ travel modes of mountainous cities are analyzed,all of which are significantly different from those of plain cities.Based on the layout mode of bus lanes,this paper explores the layout of bus lanes in mountainous cities from the perspectives of lane setup methods,intersection entry lanes,and road section exits.Secondly,the appraisal index of applicability of bus lanes in mountainous cities was selected.This article selects 12 evaluation indexes from the aspects of passengers,vehicles and road sections.Based on the basic indicators of the evaluation of bus-only lanes in plain cities,this paper proposes evaluation indicators such as motorcycle occupancy rate,right-turn social vehicle delays,and lane-only vacancy rates according to the unique geographical environment of mountainous cities.The speed model and time model were optimized for the particularity of mountainous cities,and provided support for the comprehensive evaluation of subsequent dedicated lanes.After analysis,this article selects the Topsis method as a comprehensive evaluation method for mountainous urban bus lanes,and introduces the entropy weight method to determine the index weight,and builds a comprehensive evaluation model suitable for mountainous city bus lanes.Finally,taking the mountainous city of Chongqing as an example,the applicability of the three bus lanes in Chongqing is comprehensively evaluated.This paper not only analyzes and evaluates the status quo after Chongqing’s bus lanes are set up,but also uses Vissim software to simulate and calculate the traffic conditions before the lanes are set up.It compares the changes of the indicators before and after the set up in detail,and also analyzes the mountain cities The applicability of bus lanes is analyzed.The results show that the applicability of bus lanes in mountainous cities is better,but there are still high congestion rates in sections,poor headway stability of buses,serious delays in rightturning social vehicles,high idle lane rates,and motorcycle lane occupation.The problem remains to be solved.Therefore,this paper further refines the length of the interweaving zone under different traffic volume by establishing a model of the length of the interweaving zone turning right.And from the aspects of the setting form of the interweaving area,the setting of the right turn starting point markings,vehicle management and special road management,etc.,it puts forward optimization suggestions for the improvement of the mountain bus special roads.