In order to clarify the longitudinal running speed characteristics of vehicles at the entrance,exit and connection sections of high-density interchanges,five interchanges in Chongqing were selected for the study,and a minibus driving test with 47 drivers was conducted.The data collected by speedbox and mobileye,including vehicle speed and longitudinal acceleration,were processed and extracted by entrance,exit and connection sections,and the corresponding speed profiles were plotted to clarify the longitudinal operat-ing characteristics of vehicles at entrances and exits of high-density interchanges and connection sections.The analysis results show that there are two types of speed trends at the entrance,parallel entrance is rising-steady and direct entrance is continuously rising,the mean value of parallel entrance speed is higher than that of direct entrance,and the standard deviation of parallel entrance speed is smaller than that of direct entrance;different types of entrances have certain influence on the driver's choice of acceleration operation;parallel entrance has lower mean value of longitudinal acceleration than that of direct entrance.The overall speed distribution at the exit shows a smooth downward trend;the mean value of running speed of parallel type is lower than that of direct type,but the standard de-viation of speed is higher;the characteristic point of exit speed change is influenced by drivers'preference of deceleration at the exit of main line;the maximum value and mean value of exit deceleration of parallel type are larger than that of direct type;when the net dis-tance between adjacent interchanges is shorter,the speed change of connecting section is flatter and the speed amplitude of different drivers is closer.In contrast,the velocity volatility of the connecting section is large and discrete for adjacent interchanges with regular clearances.The research results provide theoretical support and basic data for the safety evaluation and improvement of the entrances and exits of high-density interchanges and their connecting sections.
high-density interchangesmall spacing interchangefield driving testentrance and exitoperating speedlongitudi-nal acceleration
维普
万方数据
