DEVELOPING DENSITY CONTROLS FOR IMPROVED TRAFFIC OPERATIONS

Abstract

TRAFFIC THROUGH A SINGLE-LANE ROAD SECTION WITH A BOTTLENECK AT OUTPUT IS CONSIDERED AS A SYSTEM INVOLVING INPUT FLOW, SECTION DENSITY, OUTPUT SPEED, AND OUTPUT FLOW. EFFECTS OF OUTPUT FLOW ON OUTPUT SPEED ON SECTION DENSITY, AND SECTION DENSITY ON INPUT FLOW ARE SHOWN. FOUR CASE STUDIES ARE DESCRIBED, EACH WITH DIFFERENT PATTERNS AND LEVELS OF TRAFFIC PRODUCTION. CONSISTENT RELATIONS AMONG SECTION DENSITY, OUTPUT SPEED, AND OUTPUT FLOW ARE OBSERVED. FLOW IS AT A MAXIMUM WHEN OUTPUT SPEEDS ARE IN MIDRANGE. OUTPUT SPEEDS ARE A DELAYED INVERSE FUNCTION OF SECTION DENSITY. THE EFFECT OF AN EARLY AUTOMATIC SYSTEM FOR CONTROLLING SECTION DENSITY BY LIMITING INPUT FLOW BASED ON MEASURING OUTPUT SPEEDS IS DESCRIBED. /AUTHOR/