THE INFLUENCE OF MULTIPURPOSE LANES ON TRAFFIC FLOW ON TWO-LANE PROVINCIAL ROADS

DER EINFLUSS VON MEHRZWECKSPUREN AUF DEN VERKEHRSABLAUF ZWEISPURIGER LANDSTRASSEN

HEAVILY LOADED TWO-LANE ROADS WITH MIXED TRAFFIC AND A HIGH PROPORTION OF SLOW TRAFFIC HAVE IN THE PAST BEEN CONSTRUCTED SOMETIMES WITH AND SOMETIMES WITHOUT MULTIPURPOSE LANES, ON THE BASIS OF THE FEDERAL GUIDE TO CROSS SECTIONS. ONLY VALUES GAINED FROM EXPERINECE WERE AVAILABLE FOR THE LIMITS OF APPLICABILITY AND THE PERMISSIBLE LOADINGS OF THE TWO COMPARABLE CROSS SECTIONS. THE OBJECT OF THE RESEARCH IS TO DETERMINE SUCH LIMITS BY STUDIES OF TRAFFIC FLOW ON TWO-LANE ROADS WITH GENERAL- PURPOSE LANES. BY MEANS OF JOURNEYS THROUGH TOWNS, AN INVESTIGATION WILL BE CARRIED OUT INTO THE QUESTION AS WHETHER AND WITH WHAT LOADING BY VEHICLES PARKED ON THE GENERAL-PURPOSE LANE THE FLOW OF MOVING TRAFFIC FALLS BELOW THE PERMITTED SPEED, AND WHAT DANGER ARISES FROM THIS SITUATION, IF THE TRAFFIC FROM THE GENERAL-PURPOSE LANE HAS TO MOVE INTO THE DRIVING LANE BEFORE THE JOURNEY THROUGH THE TOWN. THE CRITERIA FOR THE EVALUATION ARE THE INSERTION SPEEDS, SPEED DISTRIBUTION, EXTENT AND FREQUENCY OF OBSTRUCTIONS, NONUNIFORMITY OF SPEED, FORMATION OF COLUMNS, FREE MOVEMENT AND RELATIVE JOURNEY TIME.