ACPA Quarter 3 2018

Concrete Pavement Progress www.acpa.org 6 Concrete Overlay Rejuvenates Road Ride Quality and Safety Enhanced at Lower Cost to DOT By Sheryl S. Jackson WHEN THE PLANS WERE MADE TO RENOVATE six miles of SR 9 in Grant County, Ind., sev- eral options were considered to address the distressed asphalt pavement. In the end, a thin concrete overlay was selected as the best option for the project. Not only did the project serve as a test of thin concrete overlay for the Indiana Department of Transportation, but it also proved to be a lower cost when design life was considered, says JasonHoy, P.E., design projectmanager for StrandAssociates, the engineering design firm for the project. “Annual cost per lane mile for the thin concrete overlay with a functional life of 25 years was $10,860 compared to $13,750 for an HMA two-lift overlay with a 15-year functional life.” “The state wanted to try PCC overlay, and sev- eral projects were considered,” says BradTaylor, P.E., area engineer for INDOT. SR 9 in Grant County was a good candidate to test a thin concrete overlay due to the ease of detour- ing regional traffic. “The southernmost four miles of the project were in a rural area with few homes and farms along it,” he explains. “Another highway that was less than one mile from the section of SR 9 that was used to divert regional traffic, which allowed us to close the section completely.” The complete closure allowed the contractor, Primco, Inc., an ACPA member, to pave the full 30-ft width at one time. “Our paver could run at a faster pace with no stops, but we were limited to 2,000 ft at 30-ftwide per day because our central batch plant was not big enough to handlemore,” says Rick Baumer, vice president of concrete paving operations for Primco. The size of the plant also required a change in the fiber used, he says. The fiber-reinforced thin concrete overlay was 4.5 in. placed over the existing asphalt after milling 1.5 in. and patching areas that needed repair to produce a smooth surface for the concrete. Because the design called for joints every 6 ft, there were a lot of saws needed to keep up with paving progress—especially the fourmiles that were paved full width. “This was our first thin concrete overlay project, and we needed to buy additional saws for the project,” Baumer says. “We typically run two saw crews, but we had six people sawing at one time, which was necessary for the 30-ft wide sections.” The northernmost two miles of the project were in a more suburban area with residential traffic, which meant that only one lane could be closed at a time. Communication with local residents as well as the school system’s bus transportation department was needed to make sure residents could access their homes and bus routes were not disrupted. Although Primco handled traffic control at the start of the job, after the first few days, the sher- rif’s department was called in tomanage traffic, says Baumer. Barrels and drums were used to keep traffic off the new pavement while saw crews worked, but they had to remain diligent, he says because, “Residents in the rural area would drive alongside the new pavement and would sometimes cross over it.” Another challenge Primco faced was the road elevation. The existing road elevation for a O V E R L A Y continues on page 9 »