ENTRY ASSISTANCE FOR DRIVERS AT MOTORWAY ACCESS POINTS IN CONURBATIONS

EINFAHRHILFEN AN BUNDESAUTOBAHNANSCHLUSSSTELLEN IN BALLUNGSGEBIETEN

This research, to increase safety and capacity at the entry point without significant disturbance, is based on the interpretation of tables and diagrams derived from comprehensive traffic engineering measurements. Simulations are used to investigate methods which could not be operated within the road traffic regulations. Five techniques were used: the setting up of speed limits on the motorway before the entry point; two-way and one-way lane delimitation; a model of merging traffic and speed grading in the lanes. The performance of each technique was assessed in terms of journey time and vehicle separation, lane changing, overtaking and braking. Details are given of the measurement techniques and the results obtained from a typical busy junction. Empirical studies showed that the introduction of a speed limit gave advantage to entering traffic and increased the flow but led to reduced vehicle separation. Continuous markings between the entry road and the inside lane was not acceptable. One way delimitation prohibiting a lane change from outside to inside lane at the junction would probably be acceptable with associated publicity. Simulation studies confirmed empirical results and showed the potential limitations of some techniques when traffic flows were very high. This publication was originally published in German in Forschung Strassenbau und Strassenverkehrstechnik (1982) heft 362, p1-87 and for the German abstract see IRRD 319320. (TRRL)

• Corporate Authors:

  Transport and Road Research Laboratory (TRRL)

  Wokingham, Berkshire  United Kingdom 
• Authors:
  • Maecke, P A
  • Von Ray, K
• Publication Date: 1990-11

Language

• German

Media Info

• Pagination: 85 p.

Subject/Index Terms

• TRT Terms: Access; Highway delineators; Highway safety; Interchange ramps; Speed limits; Traffic engineering
• Old TRIS Terms: Delineators (Traffic); Freeway entrances and exits
• ITRD Terms: 435: Access road; 643: Capacity (road, footway); 562: Carriageway marking; 9108: Improvement; 697: Journey time; 647: Merging traffic; 2752: Motorway; 1822: Overtaking; 648: Priority (traffic); 556: Signalization; 9103: Simulation; 5408: Speed; 624: Speed limit; 673: Traffic concentration; 2827: Traffic lane; 8538: Translation; 694: Vehicle spacing
• Subject Areas: Highways; Operations and Traffic Management;

Filing Info

• Accession Number: 00620086
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Report/Paper Numbers: T 3705
• Files: ITRD, TRIS
• Created Date: Mar 31 1992 12:00AM