01126671

English

http://dx.doi.org/10.3141/2107-03

The effects of automated speed photo–radar enforcement (SPE) and traditional speed reduction treatments (speed feedback trailer, presence of police vehicles with emergency lights on and off, and combinations of the speed feedback trailer and police presence) on speed were studied at a location 1.5 mi downstream of the actual treatment (spatial effects). Three data sets from two Interstate highway work zones were used. Field data consistently showed significant spatial (downstream) effects for SPE. The combination of speed feedback trailer and police vehicle with emergency lights off had downstream effects in some cases but to a lesser degree than SPE. Other treatments showed no significant downstream effects. For free-flowing traffic, SPE reduced the average downstream speed by 2 to 3.8 mph for cars and by 0.8 to 5.3 mph for trucks. Also, SPE reduced speeding cars by 7.1% to 23.4% (except for cars in median in Data Set 1), and speeding trucks by 4.2% to 48.3% (except for trucks in shoulder in Data Set 3). For the general traffic stream, SPE reduced the average downstream speed by 1.1 to 2.9 mph for cars and by 0.9 to 3.3 mph for trucks. When SPE was used, the percentage of speeding cars and trucks in the general traffic stream was reduced by 2.9% to 28.6%, and by 7.5% to 36.1%, respectively. SPE also reduced the percentage of cars in the general traffic stream exceeding the speed limit by more than 10 mph in virtually all cases, and eliminated such trucks in all but one case.

HRIS

09-3633

Print

pp 24-33

01142391

2009

Transportation Research Record: Journal of the Transportation Research Board

9780309126236

Figures (2) ; References (10) ; Tables (6)

Automated enforcement; Automobiles; Downstream traffic; Photo radar; Police traffic services; Speed control; Speed display trailers; Speeding; Traffic speed; Traffic violators; Trucks; Work zone safety; Work zone traffic control

Highways; Maintenance and Preservation; Operations and Traffic Management; I60: Maintenance; I73: Traffic Control

Oct 29 2009 7:41AM

• Benefit–Cost Analysis of Maintenance Decision Support System
• Benefits of Pavement Markings: A Renewed Perspective Based on Recent and Ongoing Research
• Computer-Aided Design of Passive Snow Control Measures
• Evaluation of Effects of Weather Information on Winter Maintenance Costs
• Evaluation of Speed Monitoring Displays for Work Zones in Las Vegas, Nevada
• Exploratory Analysis of Accelerated Wear Testing to Evaluate Performance of Pavement Markings
• How Drivers Perceive Visibility in Blowing Snow: Human Subject Experiments on Visibility—Viewing Videos of Blowing Snow
• Multilevel Assessment of the Impact of Rain on Drivers’ Behavior: Standardized Methodology and Empirical Analysis
• Nighttime Visibility of Prototype Work Zone Markings Under Dry, Wet-Recovery, and Rain Conditions
• Precipitation Variation and the Identification of High-Risk Wet Accident Locations in California
• QuickZone Improvement for Rural Freeway and Model Validation
• Revised Process for Work Zone Decision Making Based on Quantitative Performance Measures
• Strategy Implementation by State Transportation Agencies to Maintain Work Zone Mobility and Safety
• Thermoplastic Inlay Pavement Markings: Field Performance and Effect on Hot-Mix Asphalt