The Indiana Toll Road runs east-west across northern Indiana, concurrent with I-90 and a portion of I-80.
The 157-mile stretch provides primary connections to Chicago to the west and the Ohio Turnpike to the east. The $220 million 80/90 Pavement Upgrade for a Superior Highway (PUSH) project, funded by the Indiana Toll Road Concession Co. LLC (ITRCC), was the largest investment in the tollway since its opening in 1956.
Indiana-based Rieth-Riley Construction Co. Inc. led the design-build team. Rieth-Riley already had a long relationship with the Toll Road, including work on its initial construction in 1954.
With a contract award date in February 2016 and completion date in November 2017, the design-build team, ITR Pioneers, worked with ITRCC to develop a work schedule that would complete the massive 80/90 PUSH project quickly and efficiently while minimizing impacts on the Toll Road’s customers, particularly during high-traffic periods. One of Rieth-Riley’s advantages in meeting the accelerated project schedule was having five stationary asphalt plants within 70 miles of each other and the Toll Road and one project-dedicated portable plant.
“Having those plants spaced evenly across the corridor allowed us to reduce haul time, resulting in high-quality, consistent material, less impact on the traveling public from construction traffic, and more logistical options to choose from,” said Rieth-Riley Project Manager Jacob Kwilasz.
All about quality
ITR Pioneers wanted to provide an asphalt overlay that would deliver a smooth, durable driving surface for the duration of the design life of the overlay, if not beyond. To accomplish this, Rieth-Riley performed many asphalt mix design iterations to come up with custom aggregate gradations, custom performance-graded asphalt liquids, and optimal engineering properties, working closely with Applied Research Associates Inc. (ARA), the team’s pavement designer, to predict the performance of the asphalt overlay during the design life of the pavement. The custom-designed asphalt mixture properties were used within AASHTOWare’s Pavement-ME Design software to develop the performance predictions and confidence levels for several pavement distress criteria. Mike Harrell of ARA said the results of these performance predictions gave ITR Pioneers not only the confidence to bid and build the two-lift overlay solution that was ultimately selected, but the confidence to satisfy the 80/90 PUSH project’s performance warranty requirements and plan for minor amounts of future maintenance activities.
The mainline mix designs chosen consisted of a 3.5-in. lift of dense-graded hot-mix asphalt (HMA) binder course (Indiana Department of Transportation [INDOT] Category 5 mix, 19.0 mm with PG 76-22 P liquid), which was modified into a rich bottom layer of HMA; regressed to 3% air voids from 4% by the addition of asphalt binder. The mainline surface used a 1.5-in. lift of dense-graded HMA surface course (INDOT Category 5 mix, 9.5 mm with PG 76-22 P liquid). The shoulders received a 1.5-in. mill and fill with an INDOT Category 2 mix, 9.5-mm PG 64-22. The ramps received 4 in. of mix that consisted of a 2.5-in. binder layer of type D 19.0-mm PG 70-22, again regressed to 3% air voids from 4% by the addition of asphalt binder, making it a rich bottom modified mixture. The ramp surface was a 1.5-in. type D 9.5-mm PG 70-22.
Full volumetric quality control, utilizing a combination of plant and roadway samples, was employed to ensure pavement performance. An average in-place field density target higher than INDOT standard specifications was set (and achieved) for both the 19.0-mm binder and 9.5-mm surface courses. Density was monitored continually using non-nuclear gauges and verified with randomized core samples. Additionally, efforts to improve longitudinal joint performance included both cutting back the unconfined joint by approximately 6 in. to create a clean vertical face and then applying joint mastic to the clean vertical face prior to placing the adjoining course.
The pavement was designed for a 20-year life, with the surface designed to be milled and replaced at year 12. The mainline pavements were built with a 7-year performance warranty, providing the ITRCC even more value. The warranty includes metrics of friction, International Roughness Index (IRI), rutting, Pavement Condition Rating (PCR), cracking, and other general distress. The overall IRI on the project averages well below the initial requirement.
The crack-and-seat technique used on the existing concrete allowed the ITRCC and ITR Pioneers to utilize the existing pavement as the main structural component of the roadway.
The ITRCC decided to reconstruct the Toll Road pavement from the concrete up using the crack-and-seat method as a practical and economical way of extending the life of the roadway and reducing the level of maintenance work required in the future.
The Toll Road’s existing pavement sub-base was primarily gravel, followed by a layer of concrete that was the original driving surface and an approximately 5.5-in. layer of asphalt added to the concrete during a previous improvement project. Freeze-thaw cycles each winter had caused the concrete layer to expand and contract horizontally, resulting in reflective cracking permeating the road’s surface.
The crack-and-seat technique addresses the underlying cause of the surface cracking by fracturing the concrete pavement slabs with frequent, transverse cracks to allow for small movements in the concrete that relieve stress but do not open/close enough to develop or propagate reflective cracks in the asphalt overlay placed above it. This technique retains much of the concrete pavement’s stiffness, which is reflected in the pavement design.
After milling the old HMA down to the original portland cement concrete pavement (PCCP), crack-and-seat was accomplished with a heavy, guillotine-type metal plate mounted on the back of a truck that cracked the pavement every 18 in. Then, a tractor pulled a pneumatic roller over the concrete to seat it and create a solid connection with the sub-base.
“The subcontractor, Specialties Co. LLC, would test a section then crack the concrete, and then we would core and check to make sure it cracked all the way through. Then they would set the parameters for that section and crack the entire concrete,” said Kwilasz. “We did use relief joints in the concrete as well. Initially we did not, and then we found we were having some issues with blowups, so we reverted back to using them. We would saw-cut a relief joint, and a lot of times those relief joints would then close up in the crack-and-seat process.”
The crack-and-seat technique used on the existing concrete allowed the ITRCC and ITR Pioneers to utilize the existing pavement as the main structural component of the roadway. However, crack-and-seat is only a viable alternative for concrete pavements if the support beneath the concrete pavement is stable and the concrete pavement is in decent structural condition.
“ITR Pioneers investigated the condition of the existing concrete pavement during the pursuit phase of 80/90 PUSH to understand the engineering properties of the underlying concrete and whether it would be a viable candidate for crack-and-seat,” said ARA’s Harrell. “The pursuit investigation, coupled with the Toll Road’s successful performance of a crack/seat/overlay project directly to the east of the 80/90 PUSH project limit, convinced ITR Pioneers that this strategy would be successful again.”
In addition to pavement reconstruction, the team evaluated 53 bridges within the project area for structural and operational conditions so that improvements could be tailored to the needs of each. This portion of the work was divided into full-deck replacements, bridge deck overlays and rehabilitation, deck rehabilitation only, semi-integral conversion and link slabs, and substructure only.
“Janssen & Spaans Engineering out of Indianapolis was the lead designer on our design-build team, and they managed the inspections on the bridges and provided durability reports,” Kwilasz said. “Those reports were then submitted to the owner for review, and then a scope of work was determined. The work included a variety of treatments such as retrofits, bearings, substructure patching and painting.”
Keeping the flow
After performing a traffic study, ITR Pioneers developed a maintenance-of-traffic plan across the corridor based on live and historical traffic counts and the potential for disrupting traffic. Kwilasz said the team also tried a couple different techniques: “When we did find that the traffic started to queue, we implemented an I-Cone system, which used message boards at 4 and 8 miles before the lane closure to inform drivers of slow traffic ahead and allow them to prepare for the merge.” Work zones were equipped with technology that monitored traffic flow in real time and automatically communicated this and other information to drivers through dynamic messaging boards.
During the project’s second year, the ITRCC and team implemented the zipper merge technique in work zones, which keeps both lanes at full capacity up until the closure point. They informed the public through changes in signage and a video promoted on social media. The 80/90 PUSH project also included installation of fiber-optic cable along the corridor that will allow the ITRCC to implement an intelligent transportation system (ITS), a key road-safety initiative aimed at lifting road safety and critical incident response. In addition to dynamic messaging signs, the ITS will provide automated incident detection, variable speed limit signs with flashing warning beacons, and extensive camera coverage.
The $220 million 80/90 PUSH project was the largest investment in the Indiana Toll Road since its opening in 1956.
The 80/90 PUSH project partners maintained quality and safety throughout the aggressive schedule, which included strict lane closure requirements such as keeping all lanes open during the Memorial Day, Independence Day, Labor Day, and Thanksgiving holiday windows and on Notre Dame home football game days. “It was a very tight window, not only to get the construction work completed in that timeframe but to get it all designed ahead of time,” said Kwilasz. “We were able to achieve 65% of the paving the first year. Then in the second year, through the winter of 2016-2017, we adjusted the initial schedule based on lessons learned so that we would not impact the summer months from Memorial Day to Labor Day. The program was accelerated in 2017, and the paving was actually completed four months early.”
At the ribbon-cutting ceremony in August 2017, ITRCC Chief Executive Officer Nicholas Barr noted that the project was delivered months ahead of schedule and without a single injury resulting in lost time. He also praised the support received from local leaders and from INDOT throughout the project period, which helped make the 80/90 PUSH successful.
“This investment will mean that the Indiana Toll Road will only require routine maintenance activity over the next 20 years, with little disruption to drivers for years to come,” Barr said. “The Midwest saying of, ‘There are two seasons: winter and construction,’ will no longer apply to this section of the Toll Road. We look forward to giving summer back to the traveling public.”