Calibration of Highway Safety Manual Work Zone Crash Modification Factors, TPF-5(081), 2014

(2014) Calibration of Highway Safety Manual Work Zone Crash Modification Factors, TPF-5(081), 2014. Natural Resources, Department of


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The Highway Safety Manual is the national safety manual that provides quantitative methods for analyzing highway safety. The HSM presents crash modification factors related to work zone characteristics such as work zone duration and length. These crash modification factors were based on high-impact work zones in California. Therefore there was a need to use work zone and safety data from the Midwest to calibrate these crash modification factors for use in the Midwest. Almost 11,000 Missouri freeway work zones were analyzed to derive a representative and stratified sample of 162 work zones. The 162 work zones was more than four times the number of work zones used in the HSM. This dataset was used for modeling and testing crash modification factors applicable to the Midwest. The dataset contained work zones ranging from 0.76 mile to 9.24 miles and with durations from 16 days to 590 days. A combined fatal/injury/non-injury model produced a R2 fit of 0.9079 and a prediction slope of 0.963. The resulting crash modification factors of 1.01 for duration and 0.58 for length were smaller than the values in the HSM. Two practical application examples illustrate the use of the crash modification factors for comparing alternate work zone setups.

Item Type: Departmental Report
Keywords: Countermeasures, Crash data, Geometric design, Highway safety, Traffic control devices, Traffic signal timing, Work zones, crash modification factors
Subjects: Transportation
Transportation > Roads and highways
Transportation > Traffic safety
Transportation > Traffic safety > Work zones
ID Code: 18676
Deposited By: Leighton Christiansen
Deposited On: 29 Jan 2015 21:08
Last Modified: 29 Jan 2015 21:08