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

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.