Rewriting the Playbook
When the Chicago Bears and the Green Bay Packers met last September 29 for the first game in the renovated Soldier Field, there was much more at stake than just football. In play was the reputation of Chicago's venerable lakefront landmark and the Building Team who devised a new playbook for stadium design and construction.
"The project was about more than building the best stadium. It was about creating an environment that worked with this unique city," said Carlos Zapata, who (with Ben Wood) served as project principal with Boston-based Wood + Zapata, one of two firms of the project's architectural design team LW+Z. Wood + Zapata had primary responsibility for architectural design, while Chicago-based Lohan Caprile Goettsch Architects handled the master plan and North Burnham Park.
The $606 million project was aimed at creating a state-of-the-art stadium within the footprint of the existing field and to link Soldier Field to Lake Michigan and the adjacent museum complex — the Field Museum, Shedd Aquarium, and Adler Planetarium. All this had to be done in a mere 20 months to meet the Bears' 2003 season opener.
Designed by Holabird and Roche and built in 1924 as public multipurpose sports venue, the originally named Municipal Grant Park Stadium was renamed to honor the military personnel who died in the Great War. Easily recognized by its 64 Doric columns, the stadium has hosted everything from boxing matches and stock-car races to concerts and religious festivals. When the Bears moved there from Wrigley Field in 1971, it was the oldest stadium in the NFL. "The new Soldier Field is the first new football venue in Chicago's history," says LCG associate principal Joseph Dolinar.
Clearly, a new stadium was needed. Sports fans and civic officials alike complained about the outdated facilities and the makeshift repairs that literally held the building up. The bathrooms and concession stands were an embarrassment. Due to adverse revenue-sharing rules and inadequate luxury suites, the Bears' annual income from Soldier Field ranked 28th of the 31 NFL teams. But it took 13 years of public and behind-the-scenes wrangling before the plan was approved in 1999, and another year or two to get the design in place.
A game plan for communication
"We had an entire playing field of consultants to achieve the project's objectives within that tight space and time frame," said LCG principal Joseph Caprile. "One of the keys to getting this project done was having our goals and schedules laid out at the beginning so everyone knew what they were to accomplish."
Drawings were fast tracked to meet the schedule. "We always had two tracks, one for design and construction, the other for approvals and signoffs," says Caprile. "Those two schedules were invariably linked, and the entire team was tied into them. They were the lifeblood of the project."
Web-based ProjectTalk software was used to manage more than 3,000 design drawings and documents at a given time. The team also employed a process called "team contracting," which involved everyone reviewing architectural documents for completeness and constructability, and suggesting alternate products and methods as the design progressed.
The renovated Soldier Field proves true to Chicago’s reputation as the city that
works. Completed in just under 20 months, Soldier Field features 61,700 blue seats in several tiers, 8,000 club seats, and 133 luxury suites, offering fans expansive views of Lake Michigan and the city’s unmistakable skyline. In addition, the stadium’s 64 Doric columns have been restored, standing strong against the new structure as a memorial to the men and women who served in the armed forces.
"The construction team was on board early so that we had a buildable project on day one of construction," said Mark Simonides, project executive with Turner Construction, one of the project's three general contractors, along with Barton Malow Co. and Kenny Construction Co. This was essential for the contractors to be able to squeeze a state-of-the-art stadium within the confines of a historic structure that was 80 feet narrower than most NFL stadiums.
The team toured stadiums around the world to study best practices, but they didn't just copy. "Soldier Field's unique shape gave us the opportunity to go beyond typical stadium design," said Anthony Montalto, Wood + Zapata studio director and project director. "We created a design specific to the site that provides a better experience for the fans."
The narrow bottle-shaped bowl made it impossible to put suites on both sides of the field. The design team devised an asymmetrical solution with suites stacked on the eastern side of the stadium. The stacked suites feature a combination of low-iron, nonreflective glass in a design that eliminates vertical mullions, thus providing unobstructed views of the field while minimizing glare and reflection. The skyboxes have operable awnings that can be adjusted to draw in the roar from the crowds and the action on the field.
On the west side, cantilevered seating guarantees fans unobstructed views of the city and the lake and takes them much closer to the field than had been the case in the old stadium, whose low-pitched seating configuration pushed fans away from the playing field.
To construct this new bowl arrangement — the first of its kind in the U.S. — the team decided on a skeleton of structural steel and precast concrete. "Steel is a lot more conducive to constructing in Chicago weather," said Simonides. "It's faster, and we were able to have the materials in front of us with the upfront lead time we had secured for steel fabrication."
The team used the 3-D modeling program Xsteel, by Tekla, to detail the steel frame. "If you can model it in 3-D, you can build it," said Joseph Burns, managing principal, Thornton-Tomasetti Engineers, Chicago, the project's structural engineer.
"The software helped us understand the interaction of the systems and the opportunities," said Caprile. It did require a shift in workflow, however: The design team needed to commit to details much earlier in the process in order for the structural engineer to determine precise dimensions to create the model. When construction began, the steel was on site and ready to go, enabling steel erection to begin 12 days ahead of schedule.
Running down the clock
Even as the Bears were concluding their 2001-02 season, demolition crews were at the ready. Nine months of site preparation, including the demolition of an adjacent six-story park district building, enabled demolition to begin four hours after the final whistle.
The opening challenge was to manage the unexpected abatement of hazardous soil below the stadium. The stadium sits on landfill from a 1920s freight tunnel excavation, creating a work surface that could not support multiple cranes at a time. Using concrete rubble from the demolition, the construction team created a pad that could take the weight on many cranes. "With more than a million dollars of construction put in place per day, we needed to be ready for the unexpected with decision makers on site," says Simonides.
Building phases overlapped substantially, with simultaneous work on the east and west sides of the stadium. "We worked in a circular pattern around the stadium," says Burns. "Different crews would complete their jobs in a section and move into the next. There was activity all around." Given the short timeline, the Building Team didn't have the luxury of postponing precast work until all the steelwork was complete, so the cranes that put up the steel by day installed the precast at night.
To keep on schedule, close communication with OSHA and union leaders was essential. A bar-coded ID system was used to make sure that the right teams were on site to complete the job on time. "I could go to the Web site at any time and check to see which subcontractors were on site," says Simonides.
The old stadium was surrounded by 66 acres of parking lots and pavement. Now, the 98-acre area surrounding the stadium contains 80 acres of parkland, a veterans' sculpture and water wall, a children's garden, a terraced park, a police memorial garden, a winter garden, and a sledding hill.
The team put much of the parking in two underground garages, a four-level structure on the north side and a two-story garage just south of the stadium. The precast concrete north garage connects directly to the stadium and serves the Museum Campus on non-event days. Landscaping covers the garage, completely hiding vehicles and enhancing the parkland setting. Precast was chosen over poured-in-place concrete due to schedule demands. According to Dolinar, "Precast was also more cost effective and allowed for placement during even the coldest Chicago weather."
Excavating the parking garages yielded 120,000 cubic yards of dirt and debris, which was used to create a sinuous landscape of greenbelt berms and pedestrian pathways. "It was environmentally the right thing to do," says Peter Lindsay Schaudt, principal of his namesake landscape architecture firm in Chicago.
To continue these rolling, natural forms above the parking garage, Schaudt employed structural plastic foam covered with nine inches of soil. "Most observers would never guess that it actually conceals parking," he says. "This project is designed to fit well within its surroundings and respect the Burnham vision, but not hark back to the past."
The new stadium had its critics even before the opening kickoff. Blair Kamin, the Pulitzer Prize-winning architecture critic of the Chicago Tribune, called the bowl-on-column solution a "nightmare." Ordinary citizens and visitors used phrases like "UFO," "toilet bowl," and "Mistake by the Lake" to describe it. The editor of this magazine (who recused himself from judging this entry) called it "the $606 million calamity."
Despite the critics, construction proceeded apace — in fact, ahead of pace — and the new Soldier Field is now a sea of 61,700 blue seats, an enlarged concourse, two 86x23-foot video boards, 8,000 club seats, and 133 luxury suites. The new park is popular with city residents and visitors. The historic colonnades have been renovated (although, contrary to Chicago Park District assertions, they are not always open to the public), and a 250-foot-long granite wall sculpture honors the men and women who served in the armed forces.
Once again, Chicago lived up to its reputation as the city that works.