No news is good news on many a roadway project.
With no hotline calls coming to the public engagement team led by Kimley-Horn, construction looked to be going off without a hitch from a public perception side, and the public was right.
Like ghosts in the night, the Granite Construction team managed by Zach Schweinsberg, Project Manager, completed the SR-26 bridge joint repairs, adding new life to the confluence of roadways in Riverdale.
Mind the Gap
The SR-26 bridge, originally built in 2006, was working well except for two critical junctures—the expansion joints between the bridge deck and approach slab.
The gap from the expansion joint only widened at the surface—nearly eight inches, according to the project team—but created ongoing issues for the traveling public. Repairs in 2013 and consistent maintenance were effective bandaids to keep the joints safe and smooth, but not permanent solutions for such essential infrastructure.
At 8–10 inches wide, the bridge would need more steel, both physical and metaphorical, to endure the rigors of daily travel from an average of 52,000 vehicles. The project team wasn’t interested in chiseling away at the old to find a new solution, said Travis Jones of UDOT’s Structures Division.
Instead, “We hit [the problem] with a sledgehammer.”
They used the full force of expertise, high-end materials, and a best-in-class project team to close the gap for good.
Fill the Gap
Closing the existing joints would require a bevy of materials: rebar would nearly double in size from the previous joints, giving the joint closure the needed steel to remain closed for the life of the bridge.
It led to an early complication, according to Guy Evans, Resident Engineer for designers and owner representatives HW Lochner. “We couldn’t detour people during the day,” he said. “We had to have traffic flowing in the morning” in time for everyone’s daily commute.
Speed, stealth, and precision were the themes for the project, according to the various team members. Schweinsberg said the team streamlined the process by pre–saw cutting the removal phase lines in the concrete to ready it for demolition work on the succeeding night. This concrete precutting halved the projected construction time by allowing the crews to work on both joints in a single night shift.
To deal with the traffic volume and limited construction window, the construction team bought in 73 CY of Rapid Setting Hydraulic Cement Concrete to work its magic. The concrete, Evans said, came in a volumetric truck that mixes the specialized concrete to exact specifications seconds before placement into the joint.
“You can walk on it in an hour and drive a semi over it two hours later,” said Evans of the high-strength, quick-curing concrete. It was the perfect product to seal in steel and resiliency—and seal up the joint.
Matt Rink, also from UDOT’s Structures Division, explained that each night, the project team would install traffic control, jackhammer and saw cut to remove the existing concrete and rebar, then put the new rebar back (totaling 21,821 lbs of rebar), pour the rapid-set concrete, remove traffic control, and effectively disappear—all before the clock struck 6 A.M.
New Joint
As one joint closed, another opened. The combination of HW Lochner’s Evans and the UDOT team led by Jones and Rink designed an entirely new joint to tie the bridge deck to the approach slab, relocating the new compression joint to the end of the approach slab and concrete roadway.
Just 25 feet away, saw cuts and jackhammers returned to provide a rhythm to the night. Crews cut away three inches of concrete to place the new EMSEAL compression joints, highly durable, rubber-topped foam that bonds well to concrete and expands and contracts with any thermal expansion or shifting from the two sides. Instead of expansion occurring between the approach slab and bridge, it is now happening between the approach slab and concrete roadway, said Schweinsberg.
Crews also removed four feet of rebar from the approach slab as they worked to close the old expansion joint. Schweinsberg said that, because of the tight working areas at the bridge, it was nearly impossible to obtain enough lap between the existing and new rebar.
“By using mechanical couplers, we were able to attach the new no. 8 and no. 9 bars while only exposing six inches, as opposed to 48 inches for required lap length,” he said in regards to the special order transition couplers
that made the tie-in possible. The couplers also reduced the removal footprint and and made traffic maintenance more feasible.
On this new joint portion, too, designers had nothing but praise for the construction team and their work. Evans said, “Granite [Construction] really shined on this. Their production rates were double what we anticipated.”
Both joints were replaced across the entire roadway in just 13 nights, while parapet repair and more constituted the other six nights crews spent on the project so far.
The experience between the trade partners, Rink said, made this a sequencing dream. “It was the A-Team all the way across the board.”
With old joints closed and new joints created, the project is just a few more workdays away from full completion. Once the weather warms up, the Granite Construction crews return and complete the final phase of their work. Like a special forces team placed into a hot spot, they will add in the thin-bonded polymer overlay and concrete coating to get the bridge back to its transit-supporting best.
SR-26 Bridge Joint Repairs
Location: Riverdale, Weber County
Cost: $967,769
Project Team
Owner: UDOT
Owner’s Rep:
HW Lochner
Public Involvement: Kimley-Horn
Prime/General Contractor: Granite Construction
Subconsultants: AAA Barricade, American Pavement Markings, A-Core, Forte, Western Paving Inc, Comers Concrete, Protech and B Jackson