METHOD FOR THE LONGITUDINAL DESIGN OF ACCELERATION AND DECELERATION LANES ON ROADS

ERSTELLUNG EINES BEMESSUNGSVERFAHRENS FUER DIE LAENGENENTWICKLUNG VON BESCHLEUNIGUNGS- UND VERZOEGERUNGSSTRECKEN IM STRASSENBAU

THE LENGTH OF ACCELERATION AND DECELERATION SECTIONS IN THE AREA OF ROAD JUNCTIONS OR AT THE END OF CRAWLER LANES IS MAINLY DETERMINED BY MOTOR VEHICLE CHARACTERISTICS (ACCELERATION CAPACITY, BRAKING, POSITION ON THE ROAD, WEIGHT, WORKING LOAD ETC). THEREFORE IT WILL BE NECESSARY TO CARRY OUT TESTS ON DIFFERENT VEHICLES TO DETERMINE THESE CHARACTERISTICS AND TO COMPARE THEM. RESULTS OF THE EVALUATION OF NUMEROUS MEASUREMENTS OF ACCELERATION AND DECELERATION VALUES FOR A SUFFICIENTLY LARGE AND REPRESENTATIVE SAMPLE OF VEHICLES WILL HAVE TO BE CONFIRMED BY ESSENTIAL PARTS OF THE TEST PROGRAMME: SUBJECTIVE EVALUATION OF VEHICLE BEHAVIOUR UNDER VARIOUS DRIVING CONDITIONS, PEDAL FORCES AND RESULTING BRAKING DECELERATIONS, ENGINE BRAKING, INFLUENCE OF BRAKING AND CHANGE OF LANE ON DRIVING COMFORT. THE AIM OF THE WORK IS TO PRODUCE DIAGRAMS OR FORMULAE WHICH, IN RELATION TO THE AVAILABLE DESIGN ELEMENTS OF THE ROAD (RADII OF CURVATURE AND GRADIENTS), DETERMINE THE LENGTH OF THE REQUIRED ACCELERATION AND DECELERATION SECTIONS. CONSIDERATION IS ALSO TO BE GIVEN TO THE UPDATING OF THE RESULTS OBTAINED IN LINE WITH CHANGES IN VEHICLE CHARACTERISTICS.