Extent of traffic shockwave velocity propagations induced by U-turn facility on roadway segments

The paper is aimed at determining the extent of traffic shockwave velocity propagations induced by U-turn facility on a dual carriageway. Often U-turn traffic movements at roadway segments are channelized and aided with splitting islands so that drivers can be on their desired trajectories. Drivers will have to keep to the right lane; decelerate when diverging, accelerate when converging. These dangerous manoeuvres beg the question; ‘what are the induced traffic flow consequences when the lead vehicle decelerates or accelerates abruptly? Based on the hypothesis that U-turn facilities at roadway segments may cause traffic shockwave velocity propagations; impact studies were carried out at two locations, Malaysia during daylight and dry weather conditions. Traffic volume, speed, and vehicle types’ were collected continuously for eight weeks from January to March 2012 for both directions. The survey data were supplemented with highway design information culled from the Malaysian Public Works Departments manual. Traffic shockwave velocity propagations were estimated for roadway sections with deceleration and acceleration midblock U-turn carriageway lanes and then compared. Results show that traffic shockwaves induced deceleration and diverging, are less severe than those caused by acceleration and merging. The paper concluded that U-turn facilities will induce traffic shockwave that may cause road accidents.


  • English

Media Info

  • Pagination: 9p
  • Monograph Title: The Australian Low Carbon Transport Forum: identifying the greenhouse gas abatement potential of the Australian transport sector

Subject/Index Terms

Filing Info

  • Accession Number: 01455644
  • Record Type: Publication
  • Source Agency: ARRB
  • Files: ITRD, ATRI
  • Created Date: Nov 30 2012 2:42PM