The Michigan Department of Transportation (MDOT) has embarked on an Interstate 75 improvement project in Monroe County, replacing pavement and updating interchanges to make the road safer for the traveling public.

"The pavement condition is the reason behind the project being built," says Greg Losch, MDOT Engineer in charge of the I-75 project. "You drive through there, and the concrete is falling apart and needs to be replaced."

Approximately 70,000 vehicles drive on this section of I-75 daily. Between 20 percent and 25 percent of those vehicles are commercial trucks. The roadway was constructed in the 1950s, widened during the early 1970s, and segments reconstructed in the 1990s. HNTB in Detroit served as a consultant to MDOT on the pavement and Bergmann Associates of Rochester, New York, the bridge.

MDOT divided the project, which spans 20 miles from I-275 on the south to the Michigan/Ohio state line, into five projects to control the cost. Additional sections are included in the state's five-year plan and are in design. The agency will bid the other sections as funds become available.

Construction on the first $101-million, 5.6-mile phase from Dixie Highway to Interstate-275 began in June 2015 and is on schedule to wrap up at the end of 2016. Dan's Excavating of Shelby Township, Michigan, serves as the prime contractor. Scope of work includes bridge replacements and widening, culvert replacement and ramp reconstruction.

"The biggest thing with this job is the coordination," says Dennis Rozanski, Vice President and Project Manager for Dan's.

Losch described the job as expedited. It has an A plus B schedule, with a penalty of $50,000 for each day the project is late.

Dan's completed the northbound improvements on the first phase in 2015 and started on the southbound work this spring, after a seasonal suspension of activity. During construction, Dan's maintained two lanes of traffic in each direction on the southbound lanes, except for some nighttime closures. The speed limit was decreased during this period of time.

"Because the road is falling apart and we had both north and southbound traffic being maintained on the southbound lane, there were some nights when we had to close additional lanes to do some repairs," Losch recalls.

During the winter break, three lanes in each direction were open to traffic. When the southbound construction takes place, all traffic will move to the northbound lanes. 

Upgrading the Bridges

Bridges on the project required upgrades to meet current design criteria. Dan's Excavating and subcontractor CA Hull of Charter Township, Michigan, worked on all five northbound bridges simultaneously, and will do so again on the southbound side.

"Coordinating five bridges and still keep the project progressing was a challenge," Rozanski says.

Utility relocations delayed some of the bridge work, necessitating restaging of the rest of the job.

On the northbound side, three bridges required superstructure replacements and substructure widening. Two of the bridges are over railroad lines and one over a road. CA Hull of Charter completed these bridges. The bridges have steel girders. On the largest bridge, all of the girders were replaced, but not the piers. On the other bridges, crews added steel girders.

"The girders had to be replaced in kind, so as to not change the substructure too much," Losch says. The substructures were not changed because those were in good condition.

Dan's completely replaced two bridges with concrete girders. Those two bridges were on the MDOT and Federal Highway Administration scour critical list.

"We replaced the original design with scour-resistant foundations and a new structure," Losch reports.

The old roadway was dug up and then paved with concrete. The cross section is 12 inches of nonreinforced concrete on top of 6 inches of cement-treated open-graded drainage course. That sits atop of 10 inches of an open-graded drainage course. Beneath that is subgrade or the starting point.

The project also includes upgrades to signage, guardrails, median barriers, drainage, lighting, intelligent traffic system improvements and pavement markings within the corridor.

The southbound bridges will require similar work: two replacements and three improvements; five ramps; and repaving. The same type of girders will be used.

"This is the largest project I have worked on and even with the challenges, I am happy with the results," Losch concludes.

About Dan's Excavating

While the name of the contractor suggests a specialty in excavation, Dan's Excavating, founded in 1974, has left its initial roots of digging dirt to serving as a prime contractor for major projects, including large scale, high profile underground projects, site preparation, road construction and structural concrete work. Dan's now performs subdivision, private developments and electrical work.

Dan's has completed multiple projects on I-75, including a 2-mile portion of I-75 in 1998 and another 2.5-mile portion in 1999. About 75 percent of its work comes from the Michigan Department of Transportation.

"For us, this is a standard job that needs to be done by a certain time, hitting our milestones, which we plan to do again this year," Rozanski concludes.