고속도로의 K-factor와 차로별 점유율사이의 상관분석에 관한 연구

Abstract

Expressways are generally classified into urban and rural ones by the region or location of the expressway as the exclusive motorways, and also arterial highways that have medians and two lanes or more in one direction with full control of access. However, most expressways in Korea are experiencing transportation problems with increased traffic volumes and high proportions of heavy vehicles, because they are focused on a big cities in the country and are not properly linked with the small cities. Thus, it is strongly needed to study the traffic characteristics for improving the expressway traffic management system(ETMS) in expressways.

The purpose of this study is to identify the lane traffic characteristics(volume, speed, occupancy, density and K-factor) at the 8-lane basic segments for the reserved lane system aimed at Gyeongbu and Namhae expressways, conduct correlation analysis between lane occupancy and K-factor at the 8-lane basic expressway segments for the reserved lane system, and finally select the appropriate regression model between the lane occupancy and K-factor at the 8-lane basic expressway segments for the reserved lane system.

From the traffic characteristic analysis, correlation analysis of lane occupancy and K-factor, and modeling between lane occupancy and K-factor in the 8-lane basic expressway segments for the reserved lane system, the following conclusions were drawn:

ⅰ) Traffic characteristic analyses appeared to show a distinct difference depending on the direction, day of the week, time of the day and location of lane. So, it was concluded that the expressway traffic management systems(ETMS) based on traffic characteristics could be very effective in improving the safety and mobility of expressways

ⅱ) Correlation analyses appeared to show the highest correlation between K-factor and the 2nd lane occupancy and the lowest correlation between K-factor and the 4th lane occupancy regardless of the direction in expressways. So, it is concluded that the 2nd lane occupancy could be very effective in building the K-factor models of expressway

ⅲ) K-factor appeared to show a linear relationship with the 2nd lane occupancy by the high determination coefficients and valid probability(p-value) in expressways, in case of aggregating weekday and weekend. So, it was concluded that linear K-factor models could be effective in predicting K-factor for the whole week.

ⅳ) K-factor appeared to show the linear or logarithmic relationship with the 2nd lane occupancy by the high determination coefficients and valid probability(p-value) in expressways, in case of segregating weekday and weekend. So, it was concluded that linear or logarithmic K-factor models could be effective in predicting K-factor for weekday or weekend.