Two approximately 6-mile-long sections of Interstate 94 in St. Clair County and Macomb County, MI, are being reconstructed with P-1 modified concrete. John Carlo Inc., of Clinton Township, MI, is the prime contractor for both projects. The road is two lanes in each direction. John Carlo Inc. is paving two passes: a 24-foot-wide pass and a 17-foot-wide pass. Work on the north project began in May and was expected to be completed by the end of October. The south project began in August and is expected to be completed in 2009. The contract amount for the north project is approximately $34 million, and the contract amount for the south project is approximately $26 million.
"The schedule has been pretty challenging on both projects," Jason Fowler, quality control manager for John Carlo Inc., said. "The north job is both directions, eastbound and westbound. We are doing the eastbound side on the south job this year, and we will be doing the westbound side next year. To rebuild six miles of freeway in one season is pretty tough.
"Using the P-1 modified concrete is a little challenging in that you have to monitor the aggregates coming into the plant and adjust the mix as needed in order to maintain optimum gradation."
John Carlo Inc. is using a new GOMACO GP2800 paver on the reconstruction work. The machine features an automated dowel bar inserter. Instead of manually placing contraction baskets in front of the paver, the machine inserts them into the pavement as its paving. The machine also features a system that continuously monitors the vibrators that are imbedded into the pan. The vibrators control the consolidation of the mix.
"If you don't know what those vibrators are doing, you can run into issues and vibrate all of the air out of your concrete. If you are able to continuously monitor what those vibrators are doing in real time while you're paving, you can ultimately produce a better product," Fowler said.
"Both projects are longitudinally tined, which has been a little bit of a challenge lately with respect to ride quality. There has been some new equipment out in the last couple of years that measures the ride quality of the pavement a little differently than the older machines. The newer equipment measures out a 4-inch footprint on the pavement. The older equipment used pinpoint lasers to measure ride quality. The end of the laser was about the size of the end of an ink pen. With longitudinal tining, you have grooves in the road going with the direction of traffic. So, we ran into issues where that pinpoint laser would start to ride in and out of those grooves and give a false reading on the ride quality. In the last couple of years they've come out with a new laser setup that actually takes a 4-inch line to mimic what a tire is actually feeling. So, it averages out the dips and valleys of the grooves and provides a more accurate view of the ride quality."
The project is subject to the Michigan Department of Transportation's (MDOT) new ride quality specification called the International Roughness Index (IRI).
Approximately 100,000 cubic yards of concrete is being placed for each project. Approximately 300,000 tons of MDOT 4G base material has been placed for each project. Subcontractors on the north project include Posen Construction, Inc., of Shelby Township, MI (bridges); P.K. Contracting, of Troy, MI (striping); Five Star Engineering, of Southfield, MI (surveying); and Cobblestone Pavers, of Freeland, MI (restoration). Subcontractors on the south project include: L.J. Construction, of Clifford, MI (underdrain); Monument Engineering, of Macomb Township, MI (surveying); Highway Service Company, Inc., of Woodhaven, MI (signs); and Weyand Bros., Inc., of Saginaw, MI (landscaping and guardrail).