As the prime highway contractor, Shelly & Sands recently installed temporary portable rumble strips (TPRS) in a work zone in Mahoning County, Ohio. The concrete joint repair project was located on I-76/I-80 eastbound, between Bailey Road and the Ohio Turnpike, in the Warren-Youngstown area.
Ohio Department of Transportation (ODOT) District 4 requested the installation as part of an ongoing ODOT test, conducted in partnership with Ohio Contractors Association (OCA). District 4 was especially interested in testing TPRS in a live work zone, as there had been two crashes in that work-zone area in mid-July.
In an online article published July 20, 2017, the Youngstown Vindicator stated: “In 2017 in Mahoning County, the patrol has investigated 32 injury crashes in the construction zones and one fatal accident, as well as 155 crashes that have caused damage to property.”
The author of the article also quoted Jerad Sutton, a Lieutenant of the local post of the Ohio State Highway Patrol, who identified the problem. ‘“Some people also don’t pay attention when they are driving,” Sutton said, adding some are on phones or other electronic devices while driving.’
The RoadQuake 2F TPRS from PSS is designed to alert distracted drivers, through sound and vibration, as drivers traverse the rumble strips. Having driven over the strips, distracted drivers usually return their focus to their driving.
On the nights of Aug. 23 and 24, Shelly & Sands installed the PSS rumble strips in the I-76/I-80 eastbound work zone. Traffic was significant, as the area is a crossroads where two major interstates, traveling together, soon separate nearby. On both evenings, about 18,000 vehicles traveled over the rumble strip arrays—30% of the vehicles were large trucks. The interstate speed limit there is 70 mph, 55 mph in the work zone. RoadQuake TPRS is rated up to 80 mph.
Shelly & Sands deployed and removed the rumble strip arrays by rolling roadblock. The crew required only 5-8 minutes to deploy four three-strip arrays— two arrays in the travel lane, two in the passing lane.
Shelly & Sands followed the PSS recommendation of 20-ft spacing between each rumble strip in an array in speeds above 55 mph. With this spacing, at interstate speeds, drivers will hear and feel the engineered sound and vibration of RoadQuake when they drive over the rumble-strip arrays. Distracted drivers typically return their focus to driving.
In addition, Shelly & Sands reported an ancillary benefit of TPRS arrays, noticing a difference in speed reduction when the vehicles hit or approached the rumble strips. On the first night, they recorded average speeds at 60 mph entering the work zone, and 50 mph through the work zone. On the second night, they achieved similar speed reductions of 62 and 52 mph.
As the installation was a trial project, Shelly & Sands also recorded movement of the rumble strips in live traffic. About two hours after installation, the travel lane strip had moved about 2 in., while the passing lane had not moved (see second photo below). After 5 hours, the travel lane had moved about 5 in., and the passing lane strip had moved about 2 in.
PSS recommends that users routinely monitor rumble strips, like they would all temporary traffic control devices. The duration between checks will vary between jobsites, but should not exceed 4 hours. They also recommend that strips exceeding 3 ft of skewing movement should be repositioned.
Shelly & Sands measured movement of each rumble strip throughout both evenings. Some strips’ movement approached 10-12 in. over six hours. Most movement ranged between 4-8 in., and some were less, at 2-3 in. Of the 12 strips installed, no strip moved more than 15 in. on either night, during six- to eight-hour installations each night. About 18,000 vehicles drove over the strips each night, of which 5,400 were large trucks, with most of those vehicles traveling at speeds in excess of 60 mph.