Indiana-based Rieth-Riley is accustomed to adapting to challenges as they arise when a project is underway, and that proved to be the case when the company's Houghton Lake, MI division reconstructed a portion of U.S. 10 this past summer.
The approximate eight-mile stretch of two-lane highway required joint repair, cold milling and a new hot-mix asphalt overlay. The project was divided into two sections, east and west of the Village of Lake. Pavement joint and crack repair of the underlying concrete road required full-depth removal of some sections, which were then replaced with 6,415 tons of HMA.
Following the joint and crack repair, the contractor milled approximately 111,536 yards of old asphalt off the road in preparation for repaving. Before the initial leveling course could be applied, Rieth-Riley's paving crew had to place some asphalt wedging along various locations in the road to establish a correct profile to the structure.
The leveling course called for 17,251 tons of 4E3 Superpave designed asphalt at a rate of 220 lbs. per square yard, and the surface course called for 12,939 tons of 5E3 Superpave designed asphalt at a rate of 165 lbs. per square yard. The material placed had to meet a pavement ride quality specification.
Since it was a two-lane road, an intensive traffic control management program was required to minimize disruptions to motorists.
The original contract called for paving placement to extend beyond the 12-foot-wide travel lane onto the five-foot-wide shoulder. As Larry Bushong, project manager, recalls, the east section of the project proved to be a real eye opener when trying to achieve density specifications on the shoulder portion of the roadway.
"The original contract called for trenching out the shoulders a 1/2-inch deeper than the road surface after milling," Bushong says. "It was believed that the added thickness would provide enough structure when the new mat was placed across the travel lane and shoulder area. Unfortunately, when the shoulder was milled out in many places it was milled all the way down to a sandy subbase. There was just nothing there. There was no rigid structure underneath the shoulder."
On the first half of the project, Bushong's crews had to trench deeper in many areas to establish more compacted structure to the shoulder before the leveling course could be placed.
On the west portion of the project, the contractor convinced the Michigan Department of Transportation to approve a change in order to trench out the shoulder three inches below the milled surface of the travel lanes and then place three inches of 2C HMA to create a more substantial subbase before applying the leveling and surface courses.
Restricted work zone
Along with the shoulder challenge, the project presented restrictions on when and how much of the roadway could be under reconstruction at any given time.
"We couldn't have a milled section open more than three days. We had to place the first leveling course fairly soon after a section of the road was milled," Bushong says. "Basically, what we were capable of paving in a week (a four-day work week) is all that we could allow our subcontractor to mill. We generally were able to mill and pave a two-mile stretch each week and that's about as fast as we could go with the additional work required to fix the soft shoulders.
"We were somewhat restricted by when we could work on the project," Bushong adds. "We had to be off the project by a certain time on Fridays, and we couldn't have more than two closures that were no longer than two miles on a section of the road and there had to be a mile of unrestricted traffic in between those closures. And since the project was divided in half, with each half approximately four miles long, it was difficult to set up work zones within the confined project length."
With specification changes on the west portion of the project to address the soft shoulder conditions, Rieth-Riley received an extension to complete the job.