To minimize disruptions to the travelling public, MassDOT utilized rapid bridge replacement approach featuring precast concrete to replace eight bridges over eight weekends
On select weekends during the summer of 2021, MassDOT (Massachusetts Department of Transportation) replaced eight bridges along the I-90 corridor. This major project updated the decades old infrastructure and extended the life of each bridge by 75 years.
MassDOT utilized modern construction techniques and precast concrete systems to upgrade the crossings between Worcester and Boston that serves over 100,000 drivers a day while minimizing the impact to travelling public and local residents.
On I-90 in the bridge construction area, all vehicles were shifted to the opposite side of the highway using two median crossovers. Two lanes were open in each direction with temporary barriers maintaining traffic flow. Local roads were closed under the bridge being reconstructed to ensure public safety. Typically, the local roads beneath the other bridges supported detour routes for the closed road of the active bridge.
Deteriorating abutment walls and bridge decks, rusting and corroding steel made this project well needed. Not only were the eight failing bridge decks and superstructures replaced but the clearance height to local roadways below was improved. The roadway vertical profile was raised 3.5 feet to match adjacent construction and to increase minimum vertical clearance as compared to existing conditions.
The eight bridges were replaced over six weekends, requiring two of the bridges (Parkerville and Flanders Roads) to be constructed simultaneously. The remaining two weekends were set aside specifically for waterproofing and paving for eastbound and westbound respectively.
“The experience on the Fast 14 project proved invaluable to the success of this project,” says Tim Cullinane, Jr., Project Manager, J.F. White Contracting Company of Framingham, MA. Ten years earlier, JF White Contracting had successfully completed the first accelerated bundled bridge project in the state. No stranger to crews that had to work around the clock to meet the deadline at each location over the summer weekends, they took those lessons learned over 10 weekends completing the I-93 Rapid Bridge Replacement Project, known as the I-93 Fast 14. Similar to the issues faced on I-90, with multiple lanes in each direction on the highway and traffic demand requiring use of every lane, long-term closures were out of the question.
Design Build (D/B) and Accelerated Bridge Construction (ABC) provided the benefits of one source responsible for both final design and construction as well as one source for precast concrete systems. It reduced the schedule from several years to 8 weekends. The use of precast concrete elements such as abutment caps, shortened the duration of construction which reduced traffic impact. NEXT D beams required only small closure pours which lends itself to the compressed schedule. To meet the deadline, temporary barriers were placed during the rapid weekend and bridge barriers were installed with cast-in-place concrete at a later time.
JP Carrara & Sons, Inc. manufactured a total of 242 precast concrete pieces including NEXT Beams, Precast Abutments, Precast Approach Slabs and Precast Moment Slabs. The Northeast Extreme Tee (NEXT) beam offered significant advantages over other solutions by providing a fast construction option for variable-width bridges with spans up to 85 feet.
Each weekend required 60 precast pieces to complete the east and west bound bridge construction. Some of the precast concrete pieces exceeded 60,000 pounds which required a heavy crane to hoist them into place. Trucks delivering precast bridge components from the JP Carrara & Sons facility in Vermont were originally dropped at storage lot and during the weekend were staged along I-90 and local roads.
The 56-hour weekend shutdown started at 9:00 PM Friday and ended at 5:00 AM Monday. First, traffic was shifted at the two crossover points, approximately three miles apart. At the same time as one bridge was being replaced, work was ongoing at the other bridges on the same side of the highway to prepare for future replacements. For most people, the transition from old bridge to new bridge was seamless.
J.F. White Contracting, led the 56-hour construction effort using a temporary “zipper” barrier to switch traffic. The rapid weekend started with Friday night demolishing the existing bridge and preparing the existing abutment stem surface. Saturday they placed precast abutment caps and grouted in place prior to setting the NEXT D beams (precast beams with integral deck) and approach slabs. On Sunday, the moment slabs that support jersey barriers that sit directly on wing walls were installed. Then crews backfilled and paved to open the structure to traffic by 5 am Monday morning.
The Cordaville Road crossing over I-90 involved the replacement of the entire bridge which was demolished and replaced with precast components to carry the three lanes of traffic plus shoulder. The work in the other locations was for the replacement of the superstructure only.
Weekends were chosen after MassDOT evaluated the lowest traffic volume months of May through August. The project had to be completed ahead of the Labor Day weekend and they also wanted to avoid holiday weekends like Memorial Day and July 4th. After eliminating holiday weekends, the project team had 14 remaining weekends available to complete the 8 bridges, which allowed limited flexibility for potential weather and other impacts.
It took two years to develop the means to make eight bridges in eight weekends possible. Acceler-8 used single-contractor design-build management and ABC techniques. This tried-and-true strategy has been successful for MassDOT and other agencies. ABC methods utilizing precast concrete components resulted in safer and more efficient construction.