golden1 250Golden 1 Center, the newly completed, $557-million home of the NBA’s Sacramento Kings in California, welcomed guests at a ribbon cutting ceremony on Sept. 30. On hand for the opening festivities were members of Thornton Tomasetti’s structural design team, who collaborated with owner representative ICON Venue Group, architect AECOM and general contractor Turner Construction to design and build the facility on an accelerated schedule.







“After three years of fast-paced design and construction administration, and the occasional challenge, it was rewarding to attend the grand opening and share in the community’s excitement as a long-awaited landmark structure finally becomes a reality,” San Francisco Vice President Justin Fahey, who managed the project locally, said.

Thornton Tomasetti designed a repetitive, bent ladder-type framing system for the arena’s façade. Photo by Matt Cummins / Thornton TomasettiThornton Tomasetti designed a repetitive, bent ladder-type framing system for the arena’s façade. Photo by Matt Cummins / Thornton Tomasetti

Following the ribbon-cutting, the arena hosted an open house on Oct. 1 as well as a Sacramento Kings Fan Fest, which saw a capacity crowd. Golden 1 Center, which replaces Sleep Train Arena as the Kings’ home court, includes a seating bowl with general and premium seating, luxury and loft-style suites, standing viewing areas, a practice court and an outdoor courtyard and terrace. Designed to accommodate 17,500 spectators for NBA games, with the flexibility to expand to up to 19,000, the LEED Platinum venue can be configured for other sports as well as concerts, conferences, conventions, trade shows and other specialty events.

The grand entrance bi-fold doors in the open position provide natural airflow to the arena. Photo by Matt Cummins / Thornton TomasettiThe grand entrance bi-fold doors in the open position provide natural airflow to the arena. Photo by Matt Cummins / Thornton Tomasetti

The Structure
The 780,000-square-foot arena features high roof trusses that measure 394 feet by 342 feet, including two primary queen-post box trusses that have a total truss depth of 55 feet at mid-span. A grand entrance with five aircraft hangar doors is supported by sloped entry columns. The doors fold vertically to tuck under the low roof soffit. Three of the doors remain partially bent, or kinked, while in the closed position, which required a custom door design from the manufacturer, to blend in with the pattern of the exterior cladding.

At the grand entrance, the upper concourse and suite floors narrow to form a thin strip of bridges that connect to each side of the upper bowl. These bridges provide a gathering place with views of the court and, when the doors are opened, vistas of the surrounding neighborhood.

Thornton Tomasetti served as the lead structural engineer on the project. We collaborated with Sacramento-based structural engineering firm Buehler & Buehler, which has extensive local experience, particularly with the existing development on the site. This included a parking garage that was partially reused in the design of the practice facility.

Thornton Tomasetti’s structural scope also included the design of a repetitive, bent ladder-type framing system for the façade. The façade panels are shaped in different configurations to evoke the striations of the granite of the Sierra Nevada Mountains. The 10-foot-wide by 69-foot-tall bent ladders were fully shop fabricated, shipped to the site and erected as one piece, resulting in an economical solution to a seemingly complex façade. Because the floors of the arena are set back from the façade, the ladders are supported from a ring beam bracketed outside the building columns at the loft level and clear-span to the roof.

Rising to the Challenge
A number of architectural features presented challenges to the structural design of the lateral system. The generally open floor plan, wide concourse corridors and narrow suite- and loft-level floor plates all provided limited opportunities to locate lateral force-resisting elements. To address this, our engineers used buckling-restrained brace frames (BRBFs) for the upper bowl structure to reduce the seismic demand and limit the number of braced frames required. We worked with the architectural designer to strategically place the BRBFs. The lower bowl sub-structure lateral system consists of special reinforced concrete shear walls located along the event-level corridor walls.

“Thornton Tomasetti was able to draw on our extensive sports experience in the design of the arena’s more distinctive features, such as the high-roof trusses,” Project Engineer Matt Cummins said. “We were able to develop an elegant, efficient and economical solution within the time frame necessary for construction.”

Golden 1 Center features the largest video display in the NBA. Photo by Matt Cummins / Thornton TomasettiGolden 1 Center features the largest video display in the NBA. Photo by Matt Cummins / Thornton Tomasetti

An Accelerated Schedule
To meet the proposed 22-month erection schedule, the design and construction team employed a fast-track, early procurement approach, in which the structural steel contractor was engaged at approximately 50 percent design development. Under this design assist delivery approach, professionals from Thornton Tomasetti’s Structural Engineering and Construction Engineering practices worked in close collaboration with the contractor, fabricator and detailer during completion of the design. This allowed for the ordering of steel, detailing and fabrication to take place before the completion and permitting of the project.

“While the contractor procurement process did not allow Thornton Tomasetti to provide full advanced project delivery services, this project demonstrates the best of what our Construction Engineering practice has to offer,” Managing Principal Steve Hofmeister, who served as principal in charge of the project, said. “From the construction sequence planning and the enhanced model, to the constructability and erection studies for the long-span roof and façade, we delivered integrated structural engineering and construction engineering services on this project.”

The design and construction team effectively utilized building information modeling, including Tekla steel 3D model review, to help meet the tight schedule. The design team provided steel designs in an enhanced Revit model, which was then used by the detailer to create a Tekla model with minor adjustments. This 3D model was then sent back to the design team for shop drawing review. Performing the review in this way, instead of the traditional 2D shop drawing review process, allowed for more accurate reviews and saved considerable time in the detailing and fabrication schedule.

“The paperless shop drawing review process enabled us to quickly review members and their associated end connections in a 3D environment,” Senior Vice President and lead project manager H.B. Warner said. “This is definitely the wave of the future.”

Green and High-Tech
Golden 1 Center is one of approximately 30 LEED-certified sports facilities in the United States, but it is the first to achieve LEED Platinum. A rooftop solar array and nearby solar farm provide 100 percent of the arena’s energy.

Unlike other arenas in the United States, air conditioning for the lower bowl is delivered through ventilation openings in the risers of the precast seating units. Thornton Tomasetti coordinated the design of the precast seating units to accommodate these openings and configured the riser stem depths to create duct plenums beneath the seats. This has proven to be a much more energy-efficient design than the conventional approach of blowing cool air down to the lower bowl from ducts hung at the high roof level.

In addition to being green, Golden 1 Center features the latest technologies powered by fully redundant fiber optic facilities and two, 100-gigabit Ethernet dedicated internet circuits. The arena has more than 1 million square feet of high-speed Wi-Fi ability to handle more than 225,000 Instagram posts per second as well as cellular coverage.

Golden 1 Center also features the NBA’s first in-stadium 4K Ultra HD video board. The four-screen Panasonic display is the largest in the NBA, and is seven times larger than the previous one at Sleep Train Arena. To accommodate the screen, our engineers designed a larger than normal hoist platform supported by the roof framing to accommodate the four hoist machines that are synchronized to raise and lower the scoreboard.

“Thornton Tomasetti is proud to have been involved in the design of this facility,” H.B. said. “We wish the City of Sacramento and the Kings all the best with this beautiful, state-of-the-art sports complex.”

Kicking things off at the new multi-purpose arena are concerts by Paul McCartney on Oct. 4 and 5, and WWE No Mercy on Oct. 9, after which the Kings will play their first home game the following day.

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Thornton Tomasetti provides engineering design, investigation and analysis services to clients worldwide on projects of every size and level of complexity. We are a 100% employee-held organization of 1,200 engineers, architects, and sustainability and support professionals collaborating from offices across the United States and in Asia-Pacific, Europe, Latin America and the Middle East. We focus on providing a diverse suite of integrated services and leading innovation in our industry to ensure the continued success of our clients.

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