The NFL’s best venue prize may go to the Indianapolis Colts’ new home. Whether it “wins” or not, precast concrete features make the stadium a standout.

By Greg Snapper

John P. Klipsch said it first: “Indiana Stadium will be the best football venue in America.”

Indiana Stadium, now called Lucas Oil Stadium after a March 1, 2006 buyout of the stadium’s naming rights, will seat 63,000 during regular season NFL play. As a Super Bowl host, capacity could stretch to 70,000. It will house Indianapolis Colts football, NCAA basketball championships and scores of major conventions. Renowned for its stadium designs, architect HKS Inc. of Dallas designed the stadium with”From all the architectural drawings I’ve seen to date, I believe the new stadium could be an award-winner,” said Klipsch, executive director of the Indiana Stadium and Convention Building Authority in Indianapolis. “But in addition to being a handsome facility, it is remarkably functional.” a retractable roof and a retractable north end zone. With these above-ground features, it will soon be the jewel of the NFL, but before Klipsch’s “best venue” dreams come true, critical problems underground had to be resolved.

Beneath the 25-acre downtown site, brick and mortar sewers crisscrossed where architects envisioned the playing field – 25 feet below street level.

At varied depths between 10 and 25 feet, a lattice of 102-, 54-, 36- and 24-inch main and lateral brick sewers interwove like a series of freeways. At depths that would otherwise halt game play after stadium construction, builders were faced with five sewer relocations before surface construction ensued. The largest of the five brick sewers was the first to go.

Sewer surgery

“An arterial 1,000-foot stretch of brick combined sanitary sewer cut right down the center of where the field was planned,” said Pat Wipperman, assistant project engineer for the stadium construction management team Hunt Construction Group. “We used 102- and 54-inch reinforced concrete pipe (RCP) to relocate this first section to the perimeter of the site.”

In an r-shaped path, the concrete sewer pipe now runs along the north and west ends of the site. The concrete 102- and 54-inch sewer pipe runs west around the stadium perimeter and turns 90 degrees south once it reaches the northwest corner. The overflow from the pre-existing 102-inch brick main was originally tied into a twin box culvert sewer called Pogue’s Run, which cuts laterally through the south end of the site. The dry run of the same 102-inch brick sewer once tied into a 54-inch brick sewer south of Pogue’s Run. Both r-shaped concrete sewers now exit through the southwest corner. The 102-inch ties into Pogue’s Run and the 54-inch ties in through a directional bore to the existing 54-inch brick sewer. Both lines leave the site through their relocated paths and flow to a treatment plant southwest of downtown.

The existing 54-inch brick line on the site’s south end that now receives the 54-inch RCP dry run previously extended out into the site, running alongside Pogue’s Run. Its path on the stadium site was relocated to receive obstructing 24- and 36-inch brick sewers. With 54-inch RCP, it was relocated diagonally to the 102-inch RCP. It now tunnels along the south and follows the eastern perimeter.

The 36- and 24-inch brick sewers were relocated south on the eastern perimeter and tied into the relocated 54-inch RCP. The two smaller brick sewers originally entered the site from the east and tied into the pre-existing 102-inch brick sewer that bisected the site.

In this relocation maze, neither steel, fiberglass nor plastic was specified. Only precast concrete presented enough advantages for the field design solution.

“The specific site conditions, loads imposed on the pipes, and corrosive soils pointed us in the direction of reinforced concrete pipe,” said Stephen Starek, P.E., with VS Engineering of Indianapolis. “We specified concrete specifically because of our firm’s past experience with reinforced concrete pipe.”

Two precast concrete 45-degree bends and a T-manhole join the 102-inch RCP sewer in the northwest corner. Precision engineering and installation gave Starek and V&S what they wanted: a functionally safe 90-degree turn for the 102-inch relocation.

“We drilled partially into the wall of the 102-inch pipe and installed brackets and a steel rod to hold the pipe from coming apart from the bend elements,” Starek said. “On the spring line of the pipes, we installed three tie bars upstream and downstream of the bends just to hold it all together.” Starek said clamping the pieces together strengthened the joints. “Once fully operating, those pipes will run near to capacity, and when water flows around that corner, it will exert significant force on those joints.” With the bend strong and safely completed, VS Engineering could add the Lucas Oil Stadium to its roster of successes.

Precast concrete manufacturers, on the other hand, tend to measure success by their bid packages, craftsmanship and, of course, dollar signs. Independent Concrete Pipe Co. of Indianapolis gauges success by the bottom line too, but for the stadium, the company wanted more product supervision on the job site, so they turned to their long-time installation expert, Terry Spencer.

Spencer is field service representative with Independent for Lucas Oil Stadium. As on-site inspector, Spencer was the watchful eye over RCP delivered, installed and backfilled. Keeping tabs on the near-simultaneous installations across the site meant his reactions and judgment had to be right on. He said the concrete pipe may represent Independent’s craft, but what’s on the line is the credibility of the precast concrete pipe industry.

“My first responsibility at the job site is to the contractor,” Spencer said. “Keep in mind, however, that when the contractor is gone, Independent’s pipe will still be in the ground representing the precast concrete industry.”

“Historical evidence for reinforced concrete pipe used for these conditions in Indianapolis has shown that the pipe installed on this project will perform beyond the 100-year-design service life,” said Eric Carleton, P.E., also with Independent.

“Our competitors say plain precast pipe will always corrode and isn’t tough enough to be specified for sanitary sewer use,” Carleton said. “But here comes a major municipality building an important long-term asset, and after much review, they’re secure with the strength and reliability of precast concrete pipe to economically do the job.”

The bulk of underground work is wrapping up at Lucas Oil Stadium, but precast panel construction will begin soon on the stadium’s shell.

John Hutchings, senior vice president with HKS Inc., said brick veneer, a popular design element found in downtown Indianapolis warehouses, inspired the exterior for the stadium.

“We tried to emulate the exterior precast concrete panels around the perimeter of the stadium in a lower scale of the warehouses found in downtown Indianapolis,” Hutchings said.

HKS specified a square manganese ironspot brick to sit high on the exterior, recessed into the veneer skin to provide shadow relief and visual detailing. Hutchings is confident that the custom-designed building with Hoosier inspirations will give its tenants a sense of pride when completed in August 2008.

“We’ve come up with a refined, well-detailed exterior that will last a long time,” he said. “I think it will be enjoyed by the entire state of Indiana.”

Lucas Oil Stadium, Indianapolis

Owner: Indiana Stadium and Convention Building Authority

Contractor: Hunt Construction Group, Indianapolis

Engineer: VS Engineering, Indianapolis

Architect: HKS Inc., Dallas

Precast Manufacturer: Independent Concrete Pipe Co., Indianapolis