Freeway work zone lane capacity.

Details

• Creators:
  Notbohm, Thomas ; Drakopoulos, Alex ; Dehman, Amjad
• Corporate Creators:
  Wisconsin. Dept. of Transportation ; Marquette University. Dept. of Civil and Environmental Engineering
• Subject/TRT Terms:
  • Freeways
  • Work zones
  • Highway capacity
  • Tapers (Work zone traffic control)
  • Traffic flow
  • Traffic congestion
  • Traffic volume
  • Traffic speed
  • Data collection
  • Lane closure
  More +
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States
• Corporate Publisher:
  Smart Work Zone Deployment Initiative
• NTL Classification:
  NTL-HIGHWAY/ROAD TRANSPORTATION-HIGHWAY/ROAD TRANSPORTATION ; NTL-OPERATIONS AND TRAFFIC CONTROLS-Congestion ; NTL-OPERATIONS AND TRAFFIC CONTROLS-Traffic Flow
• Abstract:
  The focus of this report is a capacity analysis of two long-term urban freeway Work Zones. Work Zone #1 ; tapered four mainline lanes to two, using two separate tapers; Work Zone #2 tapered two mainline lanes to one. ; Work Zone throughput was analyzed throughout the day over multiple days and traffic operations conditions ; were analyzed up to a distance of five miles upstream of the Work Zone entrance. Historical data from ; pavement-embedded detectors were used to analyze traffic conditions. The database consisted of five-minute ; volume, speed and occupancy data collected from 78 detectors for a total of 50 days. ; Congestion during each analyzed Work Zone existed for more than fourteen hours each day; Work Zone ; impacts adversely affected freeway operations over distances of 3.7 to 4.2 miles. Speed and occupancy ; conditions further upstream were, however, not affected, or even improved due to significant trip diversion. ; Work Zone capacity was defined based on the maximum traffic flows observed over a one-hour period; ; throughput values were also compiled over longer periods of time when traffic was within 90% of the maximum ; observed one-hour flows, as well as over the multi-hour mid-day period. The Highway Capacity Manual ; freeway capacity definition based on the maximum observed 15-min period was not used, since it would have ; no practical application in estimating Work Zone throughput when congested conditions prevail for the majority ; of the hours of the day. ; Certain noteworthy changes took place for the duration of the analyzed Work Zones: per-lane throughput ; dropped; morning peak periods started earlier, evening peak periods ended later and lasted longer; mid-day ; volumes dropped accompanied by the highest occupancies of the day. Trip diversion was evident in lower ; volumes entering the analyzed freeway corridor, higher volumes using off-ramps and lower volumes using onramps ; upstream of the Work Zones. The majority of diverted traffic comprised smaller vehicles (vehicles up to ; 21 feet in length); combination truck volumes increased and their use of the median lane increased, contrary to ; smaller vehicles that shifted toward a heavier use of the shoulder lane.
  More +
• Format:
  PDF
• Funding:
  8591
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/26349/dot_26349_DS1.pdf
• File Type:
  [PDF - 3.98 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:cba91e2eef0036ae96ccbd8e0051909fecdc4ac433b753b5d129f067babbe989