Road User Impacts due to Speed Limit Reduction in Work Zones: Which Tool Is Best--QuickZone or VISUM?

The Utah Department of Transportation (UDOT) ExpressLink project on I−15 will increase capacity by adding express lanes in each direction from 500 North to I−215 ramp in Davis County, Utah. These express lanes will help ease the commute between Salt Lake County and Davis County. The construction requires planning work zone activities in such a way that user delay costs are minimized. Any lane reduction will increase congestion. So, UDOT instead of closing lanes will reduce both speed limits and lane widths. The paper presents an evaluation of UDOT’s procedures for deriving the user delay costs due to reduced speed limits. UDOT user delay procedures are compared to estimates from two common simulation tools (VISUM and QuickZone (QZ)). The reliability of results from these tools depends upon the type of field conditions assumed. QZ results are reliable when detour traffic conditions are neither available nor assumed in the field due to work zones. VISUM provides accurate estimations, if there are detours. The UDOT’s own procedure delivers results that are commensurate with those from QZ. In contrast, the paper shows how trip assignment modeling, through VISUM, is justified when a network provides drivers with alternate routes and diversionary paths.

• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Nadimpalli, Bhagavan
  • Martin, Peter T
  • Chaudhuri, Piyali
  • Stevanovic, Aleksandar
• Conference:
  • Transportation Research Board 89th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2010-1-10 to 2010-1-14
• Date: 2010

Language

• English

Media Info

• Media Type: DVD
• Features: Figures; Maps; References; Tables;
• Pagination: 12p
• Monograph Title: TRB 89th Annual Meeting Compendium of Papers DVD

Subject/Index Terms

• TRT Terms: Express lanes; Highway capacity; Highway operations; Speed limits; Traffic congestion; Traffic delays; Traffic simulation; Work zone safety; Work zone traffic control
• Identifier Terms: QuickZone (Computer program); VISUM
• Geographic Terms: Utah
• Subject Areas: Construction; Highways; Operations and Traffic Management; I73: Traffic Control;

Filing Info

• Accession Number: 01154463
• Record Type: Publication
• Report/Paper Numbers: 10-2678
• Files: TRIS, TRB
• Created Date: Apr 14 2010 7:14AM