Work on approximately 12 mi. (19 km) of Interstate 94 between the west Waukesha County line and County T in Wisconsin sped toward a revised interim completion date of Oct. 22. Paving was originally scheduled for completion on Nov. 3, but good weather, teamwork and a lack of serious issues along the way led to the accelerated deadline.
Incentives to hit the new target date also are encouraging crews to push, although exactly what those incentives are has yet to be determined.
“We’re coordinating with the contractor to provide incentives for the new dates,” explained Kurt Flierl, project manager of the Wisconsin Department of Transportation (WisDOT) SE Region — North Project Development. “We’ve identified the amount of time required to complete HMA paving by Nov. 3 and asked for an accelerated schedule in return for providing incentives.”
The figure is approximately $3,700 per day, which correlates to the estimated user delay cost for nighttime closures and contract administration costs.
According to Paul Piccione, WisDOT project manager, approximately 75 percent of the work on I-94 has been accomplished at night, with crews working “every hour available,” including some 10-, 12- and even 16-hour days.”
In addition to nighttime lane closures from 6:30 p.m. to 6:30 a.m., off-peak lane closures regularly occur to allow crews safer access to the busy commuter route west of Milwaukee that typically sees a daily average of 81,000 vehicles.
To provide for increased safety in work zones during so much nighttime work and because two lanes of traffic remained open in both directions during peak hours, temporary barrier walls were set up at locations of ramp reconstruction and the speed limit was reduced to 55 mph. State troopers enforced the work zone speed, gaining a little help from local news reports of a “sting” operation.
Piccione said state troopers dressed up as construction workers and staged themselves in reduced speed zones at night, with eight chase vehicles for support. What appeared to be auto levels were really radar detectors.
Piccione estimated that about 80 vehicles were pulled over, but said the real benefit came after the news reports. “We don’t care why they slow down, we just want them to slow down.”
No Bumps in the Road
While traffic was slowing down, work was speeding up. That work included repairing the underlying concrete pavement prior to resurfacing the existing pavement, widening and lengthening the WIS 83 on-ramp to eastbound I-94, lengthening and reconditioning the westbound I-94 on- and off-ramps at County C, and replacing guide signs and installing alternate route signing. Flierl counted 1,100 permanent alternate route markers along the corridor. “There were a lot of signage enhancements.”
As of early October, Waukesha-based contractor Payne & Dolan Inc. was still in the midst of paving. The lower of two layers was nearly complete. Approximately 62,000 tons (56,200 t) of E-30 mix design is being placed as a lower layer, while 40,000 tons (36,200 t) of stone matrix asphalt (SMA) is being used on the upper layer. Piccione likened SMA to Rice Krispies in texture because it contains “a lot of asphalt cement and a lot of coarse aggregate” and there are fewer small stones. “There’s a definite learning curve with SMA. It’s more porous.” About 27,000 tons (24,490 t) of E-1 is being used on the shoulders.
Flierl explained that the DOT is pursuing more use of the SMA pavement because of its long-term performance in relation to reflective cracking.
“When you overlay concrete pavement, transverse and longitudinal cracking can occur. SMA helps retard cracking. It lasts longer, so we expect better long-term performance from it.” It’s more expensive, he admitted, and more difficult to produce, but he believes the product will be well received. Payne & Dolan is responsible for producing the material and determining the correct mix design, which Flierl says has more requirements and more variation than other mixtures.
The last resurfacing of this stretch of I-94 was done in 1991. Wisconsin’s freeze-thaw cycles have contributed to cracking and general deterioration of the pavement to the point where it has reached a level of concern. The intent of this project, Flierl explained, is to address the pavement condition. Pavement distress levels have reached the threshold for improvement and WisDOT’s improvement cycle calls for resurfacing this section of IH 94 before a future reconstruction. Concrete base patching was done where joint problems were discovered. Between 1.8 and 4 in. (4.5 and 10 cm) of overlay was left in place. Variable milling was conducted to remove overlay to the correct depth for cross-slope to improve drainage. A cross-slope of 0.02 was achieved — an improvement over the previous cross-slope of 0.15.
“The job was complicated,” Piccione stated. “Over the 40 lane miles we had to rebuild, there were different aspects — at least 20 varying site conditions: slope, depth of existing asphalt, shoulder width … ”
Complexity did not stop WisDOT from trying new things. Flierl indicated that all longitudinal joints must be heated for better long-term performance.
“The joint is the most vulnerable point. Because it’s exposed to weather and water; failures usually begin there.”
Typically, the longitudinal joint between lanes is a cold joint, but in an effort to prevent future problems and avoid later costs, WisDOT planned ahead and decided to heat the joints. They “spec’ed it out as a method” and discovered it cost only about 4 cents per linear foot to heat the joint. “It cost us about $5,300 to heat the center line joint.”
In addition, because Payne & Dolan had nearby operations, the contractor was capable of producing and placing three different mixes in one night. That allowed crews to place SMA in the driving lane and E-1 on the shoulder on the same night, achieving a hot longitudinal joint for better long-term performance and strength.
“We had production nights of up to 6,600 tons,” Flierl said. “That includes three separate mixes.”
Working with a big contractor geared for interstate paving, with multiple plants in Waukesha County, was a key element in reducing the paving schedule from 14 to 9 weeks, Flierl said.
“They were able to efficiently coordinate getting the mix to the site, which helped expedite the work.”
Another experiment WisDOT tried on a portion of I-94 is an asphalt joint adhesive. Flierl explained that it’s an emulsion similar to tar and is placed along a joint prior to the placement of the adjoining surface. It acted as a sealer, primarily to prevent water from seeping into the joint. Because it bonded the surfaces, it was similar in quality to the heating method.
“We’ve tried it in a few smaller locations,” Flierl indicates, “but not on an extensive level. We may use it more in the future; we’re still evaluating it.”
One new element incorporated into the project and coordinated as a demonstration project with the Federal Highway Administration was the use of pavement marking placed across the rumble strips on the shoulders. The epoxy markings show up better at night when headlights shine on them, adding a visual clue to travel lane boundaries.
“We’re in a rural section with no lighting,” Piccione said. “This pops better at night so drivers can see where the road ends.”
In addition to work on the driving lanes, two ramps underwent improvement. The westbound exit ramp at County C was reconditioned and lengthened 600 ft. (182 m) for better deceleration. “We reconstructed the entire ramp,” Flierl said.
Westbound on- and off-ramps at County C were closed for 21 days, as scheduled, for reconditioning, opening prior to school registration. The WIS 83 on-ramp to eastbound I-94 remained open during peak hours while it was reconditioned and lengthened.
Little work remained to be completed once paving was finished. Flierl mentioned some freeway traffic management equipment that needs to be installed.
Additionally, a separate project will cover installation of cable guard at select median locations to reduce the potential for crossover crashes.
To accomplish this complex project at breakneck speed, Piccione estimated an average of 100 crew members were on-site daily. An average daily list of equipment included a few skidsteers, a skid loader, a bull dozer, an International boom auger truck, a Caterpillar rubber tire roller, 35 dump trucks, an Ingersoll road paver PF 320, an Ingersoll road vibratory roller, a main and a small milling machine, a concrete truck, a power broom, a street sweeper and a water truck. Among the equipment used on the job was a 12-ft. (3.6 m) drum mill.
Blaunox T3200 paver and a Roadtech SB 2500C shuttle buggy helped replace that torn up road surface.
But it was the dedicated DOT and contractor staff and the good working relationship that contributed to the success and speed of the project.
“We had a unique situation,” Piccione revealed. “The contractor shares an office with the department staff. If one of us has a question, we just turn and yell. It eases communication.”
A cohesive group was key on a project that let late. Typically, on a project of this size, Flierl said, work would have begun in May. However, this project did not even let until June and work did not start until the week of July 30.
Other factors in the project’s success include thorough pre-planning, good weather, public cooperation and no major surprises.
Flierl credited pre-planning and early public information with preventing problems. For example, one large supermarket distribution center along the route receives a lot of truck deliveries. WisDOT worked with them to coordinate ramp closures without impact to their operations. Pre-planning also kept the project slightly ahead of schedule and slightly under budget.
“The total cost as bid was $12,664,000. The original engineer’s estimated cost was $12,820,000. We were accurate from the start. If all my jobs went this well, my job would be easy,” Flierl said. CEG