Research On The Measurement Method And Evaluation Of The Whole Chain Accessibility Of Public Transport In Urban Agglomeration

In the context of optimizing the spatial layout,building a strong transportation country,promoting coordinated regional development and advocating transportation equity in China,it is relevant to explore a method for measuring the public transportation accessibility of urban clusters with relative accuracy and evaluating transportation equity from multiple dimensions.This paper focuses on the accessibility of public transportation in urban agglomerations through public transport.This paper focuses on the whole process of completing intercity travel by public transportation in urban agglomerations,integrates the concept of full-chain travel into the calculation of accessibility,divides the influencing factors of intercity travel into two parts:traffic impedance and traffic attraction based on the concept of gravity model,and constructs a multidimensional accessibility evaluation index system in terms of time,space,economy,transportation service level and infrastructure,etc.Each factor is also closely related to the fullchain The factors are also closely integrated with each stage of the whole chain of travel.Based on the accessibility of the whole chain of public transportation,the transportation equity is measured and evaluated from multiple perspectives through the Lorenz curve and the Gini coefficient,the Thiel index and the absolute equity index derived from the concept of Gini coefficient.Finally,the study area of the Guanzhong Plain City Cluster is used to measure and evaluate the chain-wide accessibility of intercity buses,trains and high-speed trains as well as the horizontal and vertical equity based on the chain-wide accessibility of public transportation.The results of the study show that(1)the accessibility of public transportation tends to decrease from the center to the periphery,and the variability of the peripheral areas is also significant(2)the impedance of inner-city travel accounts for more than half of the total chain travel in urban clusters on average,and is an important part of intercity travel.(3)High-speed rail brings rapid intercity travel while also widening the regional transportation equity gap.(4)Among all age groups,transportation inequity is greater among young adults;among groups with different education levels,transportation inequity is greater among highly educated groups.