DEVELOPMENT OF CRITERIA FOR INTRODUCING OPERATIONAL MEASURES TO IMPROVE BUS TRAFFIC WITHIN SETS OF LINKED SIGNALS, AND STUDY OF EFFECTS ON TRAFFIC. PART A: OPERATIONAL CRITERIA FOR BUS TRAFFIC, STAGE 1: STRUCTURE OF A SIMULATION MODEL

ENTWICKLUNG VON EINSATZKRITERIEN FUER BETRIEBLICHE MASSNAHMEN ZUR VERBESSERUNG DES BUSVERKEHRS IN GRUENEN WELLEN UND UNTERSUCHUNG DER VERKEHRLICHEN AUSWIRKUNGEN. TEIL A: BETRIEBLICHE EINSATZKRITERIEN FUER DEN BUSVERKEHR, STUFE 1: AUFBAU EINES SIMULATIONSMODELLS

A FLEXIBLE SIMULATION MODEL WAS DEVELOPED FOR EVALUATING VARIOUS METHODS OF GIVING PRIORITY TO PUBLIC TRANSPORT IN ASSOCIATION WITH THE PLANNING OF LINKED SIGNALS. THE MODEL IS TIME DISCRETE AND BASED ON MICROSCOPIC VEHICLE HANDLING. IT IS POSSIBLE TO SIMULATE A STRETCH OF ROAD HAVING UP TO 9 SIGNAL-CONTROLLED JUNCTIONS AND UP TO 6 LANES. CONTROL OF THE TRAFFIC SIGNALS AT JUNCTIONS MAY INCLUDE AUXILIARY SIGNALS FOR TURNING VEHICLES AND BUSES. THE SIGNALLING MAY BE INFLUENCED BY MESSAGES FROM DETECTORS. ALL JUNCTIONS SERVE AS A SINGLE CROSS SECTION FOR THE POISSON STREAMS OF VEHICLES. IT IS POSSIBLE TO GENERATE BUSES ACCORDING TO A PRESCRIBED TIMETABLE AT ALL SINGLE CROSS SECTIONS. ALL VEHICLES ARE ASSIGNED A DESIGN SPEED WHICH DETERMINES ACCELERATION BEHAVIOUR DURING FREE DRIVING. MOVEMENT OF THE VEHICLES IS IN ACCORDANCE WITH THE LAWS RELATING TO THE THEORY OF VEHICLE FOLLOWING, LANE CHANGES BEING ALLOWED. THE BEHAVIOUR OF VEHICLES TURNING RIGHT AND LEFT IS DETERMINED BY FIXED SIGNALS AT THE JUNCTION WHICH IS CONTROLLED BY THE NUMBER OF PEDESTRIANS AND THE VOLUME OF TWO-WAY TRAFFIC. AN EXAMPLE ILLUSTRATES THE COST OF PREPARING THE DATA REQUIRED FOR ILLUSTRATING THE GEOMETRY OF A SECTION OF ROAD.