美国养护工区特征分析

ABSTRACT

In order to characterize and estimate the scope of work zone activity across the nation, the Federal Highway Administration (FHWA) initiated a periodic web site content

acquisition and analysis effort in 2001. This activity captures a snapshot of work zone activity from selected state department of transportation websites dealing with road

closures and roadwork. Five snapshots have been taken and analyzed in the effort, each comprising roughly two weeks of work zone activity, three in the peak summer roadwork season (2001, 2002, 2003) and two in the off-peak (winter) periods (2002, 2003).The report provides a synthesis of findings and preliminary trends observed in the five snapshots.

The snapshot efforts estimated that during the peak roadwork season (summer), there are 6,500-7,200 work zones covering 20-27% of the National Highway System (NHS). Off-peak (winter) work zone activity declines by more than half, with 2,000-3,000 work zones covering 7-8% of the NHS.

The vast majority (over 85%) of work zone descriptions contain information on project duration, most (over 50%) report lane closures by time of day and number of lanes closed, few (less than 15%) provide delay advisories. From analysis of this detailed

content, roughly one-third of work zones with lane closures occur primarily at night.The most likely hoursof the day for a lane closure are9-11 AM (roughly two-thirds of all work zones), the least likely period is 6-7 PM (one quarter of work zones).

KEYWORDS: Work Zone, Delay, National Highway System, Capacity Impacts, Construction, Maintenance, Bridge Work, Incidental Construction, Website, Project Duration, Lane Closure.