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Field Measurements on the Effect of Temporary Rumble Strips in Work Zone Flagging Operations


Principal investigators:

Co-principal investigators:

Project status


Start date: 07/01/14
End date: 06/30/17


Report: Field Measurements on the Effect of Temporary Rumble Strips in Work Zone Flagging Operations (0.98 mb pdf) May 2017



About the research


Work-zone safety is a persistent problem that requires an effective suite of tools that can be applied to constantly varying conditions. The Federal Highway Administration (FHWA) summarizes the severity of the problem by noting the following in work zone crashes during the past five years:

•  More than 4,400 persons died (85 percent of which was the driver or passenger)

•  More than 200,000 persons were injured

•  Drivers are the most frequent fatality in work zone crashes

•  Most work zone fatalities involve working-age adults

•  Rear-end crashes (running into the rear of a slowing or stopping vehicle) are the most common type of work-zone crash occurring within the advanced warning and transition areas of a work zone

Limited-scale field measurements were collected to quantify the impact of two temporary rumble strip (TRS) layouts at two different two-lane roadway construction projects in Iowa. The field work was not designed to produce statistically valid comparisons for TRS effectiveness, nor contrast between TRS layouts, work zone project locations, or measured locations per site.

The findings are not comprehensive or consistent with any type of before/after or test/control evaluation. However, given the results, the presence of temporary rumble strips were found to have the following impacts as vehicles approached the work zones:

•  Increased driver braking

•  Minimal driver avoidance (driving around the rumble strips)

•  Reduced vehicle speeds

These field data are considered positive and should serve future study efforts in terms of hypothesis development and testing as part of a controlled evaluation.