ACCIDENTS AND TRAFFIC FLOW AT JUNCTIONS WHEN SIGNALS ARE DISCONNECTED

UNFALLGESCHEHEN UND VERKEHRSABLAUF AN KNOTENPUNKTEN BEI AUSSCHALTUNG VON SIGNALANLAGEN

THE OBJECT OF THE STUDY WAS TO EXAMINE WHETHER AND IN WHAT WAY SAFETY IS IMPAIRED IF SIGNALS AT JUNCTIONS ARE DISCONNECTED AT NIGHT. EXTENSIVE ANALYSIS OF ACCIDENTS - BEFORE AND AFTER COMPARISONS - AND TRAFFIC OBSERVATIONS WERE UNDERTAKEN. RESULTS SHOW THAT, OVERALL, DISCONNECTION LED TO A SIGNIFICANT INCREASE IN ACCIDENTS. THEREFORE ONE MUST RECKON ON A POTENTIAL INCREASE IN ACCIDENT RISK IF SIGNALS ARE DISCONNECTED. IRRESPECTIVE OF THEIR DESIGN AND POSITION, MANY JUNCTIONS HAD NO ACCIDENTS AT NIGHT, SO THAT DISCONNECTION OF SIGNALS CANNOT BE GENERALLY RULED OUT. IT SHOULD HOWEVER BE RESTRICTED IN SPECIFICATIONS AND BE MADE DEPENDENT ON INDIVIDUAL INVESTIGATIONS. A STUDY OF THE POSSIBILITY OF TAKING CERTAIN MEASURES IN AREAS OF VEHICLE-ACTUATED CONTROL AS AN ALTERNATIVE TO COMPLETE DISCONNECTION, IS RECOMMENDED.