美国养护工区特征分析(3)

美国养护工区特征分析

BACKGROUND

In response to increases in work zone fatalities and evidence of growing traveler frustration with delays associated with work zones, in 2001 the Federal Highway Administration (FHWA) Work Zone Safety and Mobility Integrated Product Team

initiated an effort to measure and report national-level statistics on work zone exposure and delay. Lack of data on the number and type of work zones from year to year made the formulation of national policy on work zone safety and mobility difficult, since

increases in fatalities or delay could not be examined with respect to key factors such as a potentially corresponding increase in nationwide work zone activity or exposure.

One approach to the development of national statistics on work zone activity was the automated capture and interpretation of work zone data posted to state road closure and construction websites. In order to assess the potential value of these web-based resources as a part of a national monitoring program, researchers conducted an initial “snapshot” survey of 13 state road closure and construction websites during a two-week period in the peak summer roadwork season of 2001. The pilot snapshot [1] was followed by a two-year series of semi-annual snapshot analyses for 20 state road closure and construction websites [2,3,4,5]. Two snapshots per year are analyzed to identify trends for work zone activity in what are traditionally considered off-season (winter) and peak-season (summer) construction periods.

The objective of the series of snapshots was to explore the suitability of web-based work zone data to support the calculation of measures that could characterize the extent and nature of work zone activity across the nation. In addition to documenting findings with respect to this goal, this paper summarizes observations and trends regarding work zone activity seen in data posted to state road closure and construction websites. Data

collection techniques and analysis methods are described in the next section. The paper then provides an overview of the kinds of work zone data found on state websites as well as observed trends in the form and content of state road closure and construction

websites. Last, the paper presents highlights and trends of the nationwide statistics that could be supported by the data obtained.

APPROACH

In this section,data collection sources considered for the work zone snapshot study are described. In addition, our general approach for interpreting work zone data is presented. This is a key issue given that states do not report the same data, convey the data in a similar format, or provide detailed explanation for various ambiguous data rmation regarding the location of roadwork can be found in several web-based resources. For this effort, three potential sources were considered:

1.Rand McNally Road Construction Website

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