FIRST-OF-ITS-KIND INNOVATION LEADS TO AWARD-WINNING STADIUM
BY SHERYL S. JACKSON
As the home of the Atlanta Falcons and Atlanta United, visitors to the Mercedes-Benz Stadium in A-town may be most often watching pro football and soccer, but the stadium has also hosted concerts, college football games and motorsports. Upcoming events also include the 2019 Super Bowl and the NCAA basketball Men’s Final Four.
And, while sports and music fans may come for the entertainment, the stadium itself plays a starring role in all events. Designed to hold between 66,000 and 83,000 spectators, depending on the
event and seating configuration, the stadium project, constructed by Holder-Hunt-Russell-Moody Joint Venture (HHRM JV), earned the 2018 Construction Risk Partners Build America grand award.
The 2 million-sq-ft, $1.5 billion, multipurpose sports and entertainment facility was Atlanta Falcons’ owner Arthur Blank’s vision and legacy gift to the city. The iconic design features a number of
daring formal gestures – triangular façade elements, use of an ethylene tetrafluoroethylene (ETFE) film and curtainwall façade for higher daylighting, achieving LEED platinum, an operable roof consisting of eight concurrently driven “petal” segments that open to create a Pantheonlike oculus that is 220 feet above playing level, and North America’s largest continuous video board at a sports venue – a 58-ft high, 360-degree Halo Board.
All of these features contribute to Arthur Blank’s charge to “reinvent the gameday experience” for fans, points out Wayne Wadsworth, project executive of Mercedes-Benz Stadium, HHRM JV. The project began in April 2013 in design and opened for its first event on Aug. 24, 2017. Site construction began in May 2014 – a mammoth design and construction effort delivered under a CM-At-Risk contract.
The team was selected after a design competition, which did not include any input on cost, schedule or constructability, but did promise an end date of Fall 2017. To address these issues, the team led a two-day, all-hands-on-deck meeting that resulted in a new challenge to revise the design to incorporate the value analysis ideas required to maintain the project within an updated scope and budget, with no change in the end date.
“The most unique aspect of this project, as a contractor, was the level of design and coordination that had to be completed by the design, owner, construction and trade teams — while we were building it,” observes Wadsworth. “When you set up to do first-of-its-kind innovative work, that’s what you sign up for.”
The most significant challenge was the roof structure which required HHRM to deliver a fixed roof that supports the world’s first operable roof consisting of eight cantilevered petals that open and close like a camera lens, explains Wadsworth.
While retractable roofs are not new to the NFL, an oculus retractable roof is unique. HHRM worked for months with the design team to precisely fabricate and erect steel from all over North America to create this masterpiece, says Wadsworth. “Steel was always a critical path element,” he explains. “Without steel – no roof and no dry in – which meant that we were unable to start interior construction on many of the luxury clubs and high finish areas that distinguish the building.”
STADIUM ACHIEVES LEED PLATINUM CERTIFICATION
HHRM JV contributed to Atlanta’s Mercedes-Benz stadium’s project team goal of achieving the country’s first LEED Platinum Certified professional sports stadium in a host of ways. On-site recycling of more than 90 percent of the construction waste helped achieve that mark. State-of-the-art LED stadium lighting was used to reduce operating costs and in-building recycling was used to set the standard for NFL facilities.
Other pioneering sustainable accomplishments include:
• A 1.1 million-gallon storm vault and a 680,000-gallon cistern captures and reuses rainwater for cooling tower makeup water and irrigation
• More than 4,000 solar panels produce 1.6 million kWh, enough to power nine Falcons or 13 AUFC home games
• First sports facility to pursue the LEED v4 credit strategies in the Materials and Resources category
Because of the importance of steel to the project, a Steel SWAT team was established. The prime SWAT included HHRM, the designers and the lead steel contractor, explains Wadsworth. “The SWAT integrated five structural engineering design entities, more than 32 steel fabricators, erectors and inspectors, which was no small feat,” he says. “It was simple logic that the only way to reduce information loss and non-value time lag – like time spent waiting for approvals – was to focus and expedite.”
The Steel SWAT team was assigned a conference room in which to work and meet. Meetings occurred on a daily and weekly basis to keep the focus in the right places. “We had spreadsheets, databases, tracking logs, and a hierarchy of reporting tools and mechanisms to be able to report on the status of each piece, by segment, at a moment’s notice,” says Wadsworth. “We made factory visits, site visits, inoffice visits to engineers and detailers, and reported on RFIs, bulletins and other critical documents for over four years.”
This is not the first time HHRM has established dedicated teams with one focus. “The complex nature of design and construction can create unintentional gaps or diffuse attention,” says Wadsworth. “We’ve found that assembling a singularly focused group to own all aspects of certain processes can help because they wake up each morning with no other purpose but to focus on this singular challenge.”
“We did use some new strategies, such as owning and managing a developer decision log to keep issues in front of them that were, in a sense, precluding design from being finished, and procurement and construction,” says Wadsworth. HHRM also helped with design management and at one point had three licensed architects dedicated on-site to assist with communication and coordination, and to help schedule and prioritize design efforts to keep up with construction.
Communication and conflict resolution throughout the construction process of a complex project are critical. “We set up a communication-conflict resolution hierarchy,” explains Wadsworth. Weekly principals’ meetings were held, but only the highest issues would be brought to that group. “We also had joint venture meetings, design meetings, hot list meetings, trade coordination meetings, and the list goes on. We even had spreadsheets and calendars to track the regular meetings.”
Mercedes-Benz Stadium faced never seen, seemingly insurmountable obstacles in design and construction over its several-year gestation, says Wadsworth. The HHRM JV team, with client and partner buy-in, rose to the occasion. He adds, “This stadium has redefined both the fan experience and Atlanta’s skyline.”
INNOVATIVE TECHNIQUES AND MATERIALS MERCEDES-BENZ STADIUM ATLANTA
• Steel management – 30+ steel fabricators across North America were employed to meet the demands of changing steel members and recover from missed production windows due to late design changes.
• Digital security badging system – On-site workers used digital badging and scanning to track onsite personnel.
• 4D logistics and crane sequencing – To optimize the demand for field area crane access, HHRM JV used 3D and 4D modeling via Revit, BIM 360 Glue and Synchro to produce 3D visual controls of crane reaches and workflows.
• BIM/VDC – Weekly and daily design/trade contractor coordination sessions using BlueBeam Studio with live markups to record actions, fast-forward solutions and allow days-later fabrication and installation of work were held throughout design and construction phases.
• Ethylene Tetrafluoroethylene (ETFE) – On-site mockups, 3D BIM and key work sequencing were used to implement the state-of-the-art ETFE skin. ETFE is a copolymer of ethylene and tetrafluoroethylene, refined from seawater. The durable, highly transparent, lightweight film generates 95 percent of the light, while weighing just 1 percent of glass structures.
• 4D Sequencing – 3D and 4D (3D + time) digital modeling best practices developed time-based animations of key work flow sequences for key systems such as concrete sequencing, steel erection, operable roof, MEP staging, crane and shoring tower sequencing, and other logistics.
• Roof Mechanization – Despite several operable roofs having been completed in recent years, none had yet used an eight-segment, aperture-style approach. HHRM JV captained mechanization contractors, steel fabricators, roof and skin contractors, and an army of digital scanners and layout specialists to integrate the complementary systems and ensure roof operation.