Rivals Crown State Capitol with New Dome

By Greg Lewicki

It took close to 90 years, but Oklahoma finally completed its state capitol dome in the fall of 2002-95 years after the state entered the union. According to all involved, the use of design-build was crucial to the success of the project.

"The design-build process was the only legitimate way to have approached it," says John Jamison, project executive for Manhattan Construction Co., Oklahoma City, one of the joint venture contractors. "Putting a dome on top of an existing building that is 87 years old...while keeping the legislature in session [posed] severe challenges that you couldn't depict on the normal" construction management or bid documents. "There were too many unknowns," he says.

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The original capitol architect, Solomon Layton, completed the design in 1914 and construction began that year. However, the state decided to deviate from the original design and top off the capitol building with a low, 2-million-lb "saucer" dome because the U.S. was on the verge of entering World War I, the state was short of money and steel and other construction materials were in short supply. There were rumblings over the ensuing years to finish the job, but it was not until 1994, when Frank Keating (R) was elected governor, that momentum turned in the dome's favor. Keating made it a priority to find funding and complete the dome by Statehood Day on Nov. 16, 2002. Of the project's nearly $21-million price tag, all but $1.3 million came from non-tax revenue, including $17 million that was raised through private donations.

Frankfurt-Short-Bruza Associates P.C. (FSB), Oklahoma City, completed a feasibility study for the project in 1998 that determined that the existing structure could support the 5- million-lb, 157-ft-high x 80-ft-dia dome. Once the feasibility study was completed, the Oklahoma legislature, through a special act, allowed the project to go forward using design-build. It was the first design-build project authorized by the state. FSB provided architecture and engineering services and two of the state's oldest construction companies, Flintco Inc. and Manhattan Construction, entered into a joint venture as Capitol Dome Builders, Oklahoma City. It was unanimously selected by the state in 2000.

The capitol dome project had lots of public scrutiny.

Although the two contractors were used to bidding against one another, the visibility and importance of the project compelled them to put aside their differences and work together. "We are two archrivals. Both of our companies have been in business close to a hundred years and we are the two largest contractors in the state of Oklahoma," says Mark Grimes, senior vice president of Flintco, Oklahoma City. "We've always competed fiercely with each other [but] we had to put our competitiveness aside and just do a good job because it was such an important, visible project."

From the start, the team had an organizational advantage with design-build project delivery. "I think what the design-build approach afforded this project was the marrying of the expertise of the design profession of architects and engineers and the construction expertise of the contractor at the very beginning of the project," says Fred Schmidt, FSB director of architecture. "We really had to solve together how we could accomplish not just the final design but how we would actually get there from the first day to the last day of construction."

"Extremely intricate constructibility issues were probably what led this to design-build," says Jamison. "People just had to sit down and scratch their heads and figure out the rotation and the methodology of keeping this thing alive. It couldn't have been done by any other method. Design-build was such a very, very important player in a project like this that had so many intricate things to discuss and feel through. It's not a cookie cutter; you don't just put it on the ground."

The dome also was a highly visible project that needed to withstand the test of time, be done right and serve as a beacon for Oklahomans. "This was to be a 100-year-design type of building, not a 50- or 25-year-life building," says Schmidt. Oklahoma "wanted this to meet some very high quality standards of construction. It had a very aggressive timeline in terms of beginning of construction through completion and I think those two elements together were probably the leading reasons for the choice of design-build on this project."

"I would have hated to go into that project with a competitive, low-bid process because it was an extremely difficult [project]," says Dave Brown, construction administrator for the Oklahoma Dept. of Central Services, which handled the project for the state. "The dome had to basically be redesigned from the original drawings to fit modern materials technology and the firms did an excellent job doing that....We just felt design-build was the way to go." Brown is a licensed architect and he worked closely with the team to make sure that the project went smoothly.

Dome Home

	Steel "wagon wheel" supported scaffolding.

Although FSB had never before designed a classic dome, Schmidt says the firm has experience in designing long-span structures, especially engineering airplane hangars with long, column-free spaces. The firm completed its design for the dome in 2001 using Layton's old drawings as a template. However, FSB incorporated modern materials into its design, which cut the weight of the structure from an estimated 14 million lb to 5 million lb. A structural steel framework largely was responsible for the reduction. It was designed for fast and easy placement and a "wagon wheel" of additional steel provided a temporary platform for interior and exterior scaffolding. It later was removed through the windows of the dome.

The dome itself was constructed of precast concrete panels. The team had to find the right recipe of colored sand, stone and cement to produce panels that matched the limestone used in the rest of the building. A series of hidden tracks, tie-off points and removable panels were included in the design to allow for easier maintenance. Mechanical systems were designed to evacuate smoke in case of a building fire through the dome at 50,000 cu ft per minute and to dehumidify the air at the top of the dome to protect finishes.

Dome colors symbolize state history.

One of the complexities of the project was removing the existing saucer dome, which left a gaping 80-ft-dia hole above the capitol rotunda. Since the capitol remained open during construction, the design-build team had to figure out a way to seal the opening without disturbing the workings of the state government. The team did this by closing off the fourth-floor rotunda area and soundproofing it. The rotunda then was filled with scaffolding and a work deck was installed 15 to 20 ft below the saucer dome.

During the demolition, a 6-ft-high interior plaster cornice, 7-ft-wide plaster state seal and a 28-ft-wide stained-glass skylight had to be disassembled and stored. Four historic and priceless murals painted by artist Charles Bank Wilson in the 1970s also had to be protected from debris and humidity. Since the 8-ft-high by 25-ft-wide acrylic-on-canvas murals were too large to be moved, they were protected with airtight plywood boxes in which temperature- and humidity-controlled air was pumped in from the building's ventilation system. Humidity was monitored weekly.

Another challenge was the height and breadth of the dome itself. The design-build team determined that a tower crane would be the only possible solution for hoisting precast concrete panels in excess of 15,500 lb and placing them approximately 200 ft from the tower base. The team erected the tallest free-standing tower crane ever used in Oklahoma, with a final height of 281 ft and a boom length of 230 ft.

"That was another constructibility issue," says Jamison. "How were we going to lift these big panels and demolish and take everything up and out, instead of down? It took a lot of teamwork."

Although the construction work went relatively smoothly, the team members could not control Mother Nature and there were some weather-related delays. "A big problem we had building the dome was the wind," says Jamison. "We were shut down 45 working days because of the wind. You have 25 to 30-mph winds [and] the amplitude goes up at 280 ft. We were experiencing wind factors up to 50 mph, and we had to shut down operations [because] we could not use the tower crane." Despite these frequent shutdowns, the project was not irreparably delayed.

The scaffolding also provided challenges. The entire exterior of the dome was encased in scaffolding during the erection of the steel superstructure. The scaffolding then was removed for erection of the precast concrete sections. It was replaced in sections, following the panels up the side of the dome. The scaffolding then was removed again.

On the interior of the dome, a freestanding, independent scaffolding system extended from the fourth floor of the rotunda, through two temporary work platforms and up to the interior apex (oculus) of the dome. This 140 ft of scaffolding was self-supporting and not tied to the structure at any point.

Despite the various obstacles and challenges, all involved agree that the project went off practically without a hitch. "I don't think it could have gone any better," says Grimes. "If we had done it 10 times over, I don't think it would have gone any better than the first time. There was a lot of good planning and a lot of good people on the project who knew what they were doing, [which] made a really difficult job go pretty smoothly."

A significant part of the design of the dome is its artwork, which is meant to reflect Oklahoma's heritage, particularly Native American. The state wildflower, the Gaillardia, or Indian Blanket, is the central theme for the colors of the dome's interior. A lower drum of blue symbolizes the vastness of the Oklahoma sky, and is accented with bands of gold punctuated by dark reds, blues and greens, which are meant to depict Native American beadery. At the apex of the outer dome stands a 5,980-lb, 21-ft, 9-in. bronze statue of a Native American called, "The Guardian." The artist is state Sen. Enoch Kelly Haney.

For Oklahomans, the capitol dome project took on a special resonance, especially since it was constructed in the aftermath of the terrorist bombing of the Alfred A. Murrah federal building in 1994. "It was a very special project, a once-in-a-lifetime project," says Schmidt. "It was an opportunity to be a part of Oklahoma history in the making and so everyone just rallied and everyone had their A-team on the project...and it went off without a hitch."

"We were extremely pleased with the process, everything seemed to work extremely well," adds Brown. "We were real happy with the coordination and how well [the design-build team] worked with the state."

Brown says that Oklahoma officials will continue to use design-build if a particular project calls for it. "Design-build for government agencies is coming alive now because what they found out [with the Oklahoma state capitol dome] is they want one-point responsibility, somebody that says 'I will design it, I will build it and I will guarantee the money,'" says Manhattan's Jamison.

The author, a freelance writer and editor, lives in Weehawken, N.J. He has written articles for Engineering News-Record, which he also proofreads.

All photos courtesy of Oklahoma State Capitol Dome.

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