CONDITIONS GOVERNING THE USE OF MERGING LANES AND DISTRIBUTOR ROADS AT GRADE SEPARATED JUNCTIONS

EINSATZBEDINGUNGEN FUER VERFLECHTUNGSSPUREN UND FUER VERTEILERFAHRBAHNEN AN PLANFREIEN KNOTENPUNKTEN

THE RESEARCH IS A CONTINUATION OF A PRELIMINARY STUDY (SEE IRRD NO. 700575) IN WHICH A METHOD FOR STUDYING TRAFFIC FLOW IN MERGING AREAS WAS FOUND. THIS METHOD WAS AGAIN TESTED AND IMPROVED SO THAT EVEN DENSER STREAMS OF TRAFFIC COULD BE COUNTED WITH THE ANTICIPATED COMBINATION OF TIME PLOTTERS AND VIDEO-CAMERA. OF THE SIX POSSIBLE TYPES OF CLOVERLEAF JUNCTIONS HAVING MERGING LANES OR DISTRIBUTOR ROADS, THREE TYPES WHICH ARE PARTICULARLY SIGNIFICANT FOR THE FEDERAL MOTORWAY NETWORK WERE SELECTED FOR FURTHER MEASUREMENTS. FOUR FURTHER MEASURING POINTS (MOTORWAY CROSSES AT COLOGNE-SOUTH, COLOGNE-WEST, VIERNHEIM AND BAD HOMBURG) WERE SELECTED FOR BEFORE-AND-AFTER STUDIES, SO THAT VARYING WEAVING SECTION LENGTHS AND VARIOUSLY LARGE AMOUNTS OF TRAFFIC AND DIFFERENT TYPES OF CARRIAGEWAY MARKINGS COULD BE INCLUDED AS FURTHER INLFUENCING FACTORS. THE PRELIMINARY MEASUREMENTS WERE CARRIED OUT IN THE EARLY SUMMER OF 1975. DATA OBTAINED FROM THE MEASUREMENTS HAVE TO A LARGE EXTENT BEEN PROCESSED AND ARE READY FOR STATISTICAL EVALUATION BY MEANS OF REGRESSION ANALYSES. AFTER THE JUNCTIONS HAVE BEEN REDESIGNED OR CARRIAGEWAY MARKINGS HAVE BEEN ALTERED, THE FOLLOWING WORKING STAGES ARE TO BE STARTED: CARRYING OUT OF THE SECOND SERIES OF MEASUREMENTS (THE AFTER STUDY) AT THE FOUR MOTORWAY CROSSES, PREPARATION OF THE DATA FOR STATISTICAL EVALUATION, AND INITIATION OF THIS STATISTICAL EVALUATION.