Caesars Superdome Renovation

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Caesars Superdome opened its doors in 1975, and with its innovative 680-foot clear span dome roof and iconic hourglass shape, it became a distinctive part of the New Orleans skyline. The Superdome, home to the NFL’s New Orleans Saints, is celebrating its 50th anniversary. But this is no ordinary sports venue. It hosted major concerts from the Rolling Stones in the ‘70s to three consecutive sold-out shows by Taylor Swift last year. The Superdome welcomed Pope John Paul II, Muhammed Ali, and the Republican National Convention and is also the home of the annual Essence Festival and one of the Mardi Gras parades. In addition to the Saints, the Sugar Bowl has been played there since it opened, and the stadium has held five NCAA football championships, six NCAA Final Fours, and eight Super Bowls including Super Bowl LIX in February 2025.

The Superdome is a major economic driver for the city, so when it sustained substantial damage during Hurricane Katrina in summer 2005, an extensive repair and renovation effort was fast-tracked. The building was rebuilt after the hurricane and hosted a home football game the following September 2006.

Renovating the beloved stadium was important to not only preserve its historical and cultural importance to the city of New Orleans but also to maintain the significant and consistent revenue streams stemming from the numerous events hosted there. In addition to the post-Katrina rehabilitation, the stadium has been renovated several times over the years, including notable major renovations in 1995 and 2011. The latest comprehensive renovation sought to modernize the facility, enhance the fan experience, and prepare the venue for many more years of continued use.

The capital improvements project took place over five years, but The Dome had to remain operational for each NFL season as well as major concerts and events including the NCAA Men’s Basketball Final Four. Structural design for Phase 1 began in early 2019, with construction commencing in 2020. The design continued through the 2021 season with rolling design phases and construction being completed prior to the 2024 football season.
The $560-million project consisted of 17 mini-projects spread over the five construction seasons. This article focuses on the corner viewing decks, corner atria and escalators, and corner passenger elevators.

One of the project goals was to enhance ADA accessibility throughout the stadium, including increasing accessible seating. The continuous seating bowl posed a significant challenge due to the unbroken circle formed by the precast tread riser units with only small vomitories, or passageways connecting the circulation concourses to the seating bowl. To address this, the project team introduced eight viewing decks referred to as “super-voms ”: These super-voms, or extra wide vomitories, would include ADA-compliant seating areas and standing-room-only positions in addition to access to the seating bowl (Fig. 2).

Trahan Architects’ design enhanced the overall game day experience by connecting the concourse to the seating bowl, allowing patrons to hear the crowd and catch the action on the field. To achieve this vision, significant structural changes were required. The existing seating bowl consists of a steel-braced frame system with steel raker trusses cantilevering up to 60 feet. The super-voms are located on concourse levels 200 and 500 in each corner. Each super-vom required five existing structural bents and raker trusses to be reconfigured—a total of 40 trusses—to allow the raker and seating bowl to be removed across the width of the new super-vom.

This involved reinforcing existing members and adding new members to create a revised truss layout from which the lower concourse is hung with steel hangers. The result is a new, open cantilevered platform that extends the concourse while also supporting the above stadia, the stepped floor structure supporting the seating and aisles that make up a seating bowl.

The sequencing of the steel installation and demolition of the existing bowl structure required careful planning. The team devised the following steel erection sequencing plan (Fig. 3):

STEP 1. Install new steel diagonals and truss chords and reinforce existing members. These elements created the reconfigured truss members.

STEP 2. Demolish the existing precast seating bowl. The existing single tread-riser units were lifted from the bowl as whole pieces.

STEP 3. Install the temporary hanger at each bent. The hanger system (Fig. 4) consisted of an HSS beam below the existing concourse girder with a through-bolt on either side of the girder passing through the slab and a second HSS beam on top of the slab. This allowed for level adjustments as needed. The upper HSS was welded to two pairs of strap plate hangers, which were supported by a third HSS beam welded to the top of the existing raker. The temporary hanger was located just behind the permanent hanger and near the reconfigured truss work point.

STEP 4. Demolish existing lower raker segments (Fig. 4). Deflections were constantly monitored while sequential torch cuts were made through the webs and flanges of the rakers. Minimal deflections were experienced.

STEP 5. Install new raker tub end and permanent hanger. A stub beam supporting the new cast-in-place stadia tubs, which are found at the front row nearest the playing surface, was field welded to the existing raker. The new 4-inch diameter solid steel hanger was field welded to gusset plates on the upper raker truss and lower concourse girder.

STEP 6. Gradually de-tension and remove the temporary hanger. Steel elevations were monitored before, during, and after de-tensioning and showed minimal movement.

STEP 7. Install new floor framing and slabs. Concourse floors were filled in between the now cantilevering girders. The leading edge of the concourse was curved to follow the sweeping curvature of the newly formed seating bowl, trimmed with LED video boards.

STEP 8. Install cast-in-place concrete tubs and vomitory walls. The architectural design called for curving vomitory walls that swoop upward and turn into the upturned wall of the cantilevered stadia tubs. Cast-in-place concrete allows the components to be form-fit to the existing structure, avoid heavy crane picks, achieve the architectural curves, and be built faster. It also allowed the tubs to be seamlessly joined to the rakers with the bottom of stadia perfectly flush with the raker ends without joints (Fig. 5).

All eight super-voms with their 40 trusses were demolished and rebuilt in the 2021 offseason owing to the collaboration between Thornton Tomasetti’s structural engineering and construction engineering teams, construction manager Broadmoor LLC, fabricator Postel International, and erector Foster Steel. At the height of structural construction, steel components could be field measured, shop drawings adjusted, steel fabricated, delivered, and erected in as little as one week.

Upon entering the renovated stadium, visitors are greeted by an expansive atrium, which provides a grand entry point while also enhancing the vertical transportation within the structure in three of the four corners. The main entry at the elevated plaza level (Level 100) serves as the primary gateway to the stadium. Fans ascend to designated levels via newly installed escalators. Similar, but shorter, sideline atria were also created in the new sideline clubs—space that was taken back from the original spiral sideline ramps that were demolished in Phase 1.
Creating a corner atrium required cutting 40-foot-wide by 90-foot-long jelly-bean shaped holes at four floor levels. At Level 200, the existing structure consisted of a cast-in-place concrete pan-joist system with concrete girders and columns. The demolition extents were taken to the nearest girder or joist with new steel framing, composite slabs, and curved slab edge plates built-back to create the shape of the opening (Fig. 7).

The existing structure for the upper levels, comprising 2-way flat slabs spanning to girders on column lines, were modified in a similar manner. Additional framing was added as needed to support existing-to-remain 2-way slabs where the new atrium opening created end span (fixed-pinned) conditions that were originally designed as interior spans (fixed-fixed). At least one radial flying beam at each level was kept or added to provide support for the long escalators and lateral support for the floor and facade outboard of the atrium.

The engineering challenge extended beyond simply removing existing slabs; it involved rebuilding the lateral load path. The Level 300 structure was particularly challenging because it resolves lateral component forces generated from the sloping, hanging exterior columns, which are under sustained tension. In the existing condition these forces were resolved with in-plane lateral bracing under the floor. Removal of these braces and select radial girders was facilitated by installing a 20-foot-deep horizontal truss outboard of the atrium under the low roof that redistributes the lateral forces around the large opening (Fig. 8). The truss was assembled in the field with new W12 chords and diagonals but used existing radial low roof beams as the truss “verticals.” Gusset plates and local member reinforcements were field welded to existing steel framing. Sequencing the reinforcement and build-back work with demolition was critically important to maintain structural stability throughout construction, but with careful coordination, the team was able to accomplish this with minimal temporary support.

Each atrium was clad with a “veil” of extruded, serrated aluminum tubes extending the height of the atrium. The veil shape echoes the stadium’s hourglass exterior. Connections between the veil system substructure and the attachment to the superstructure were closely coordinated between Thornton Tomasetti steel detailers and the architectural metals fabricator, Zahner. Steel bent plate brackets and curved slab edge plates were field welded to allow precise placement and supported the shop fabrication and panelization of the cladding system.

Thornton Tomasetti provided erection engineering support for the construction team and helped devise a plan to assemble the escalator on the Level 100 floor below the atrium, lift it up vertically through the atrium, then rotate it into place with final supports at each end and two intermediate levels.

Enhancing ADA accessibility required the addition of 16 new elevators. One challenge was navigating the narrow “waist” of the building, where it comes together and then widens again.
The elevator shaft was hemmed in with the circumferential braced frame and girder line on the field side and 14WF facade girts on the exterior (Fig. 10). To provide enough clearance, the girts were reinforced by welding bars to the exterior flanges and top and bottom reinforcing angles to replace the inside flanges. Then the inside flanges, which encroached on the clear hoistway, were removed and a sloping sheet metal shroud was installed to eliminate a ledge condition inside the hoistway.

Foundations for the elevator pits also proved challenging with existing pile caps limiting the pit Dome roof depths and low head-heights limiting equipment sizes. A concrete podium was built to access the elevator entry with a short flight of stairs and a ramp or ADA lift up to the podium. The foundation support for the elevator pit and podium was provided by steel open-end pipe piles driven to a depth of around 90 feet. A low-head-height pile driver was used in areas with head-heights as low as 14 feet with pile segments as short as 3 feet.

At the top of the elevator shafts that access the press boxes, the elevator overruns pass through the existing roof gutter tubs, precast concrete basins that collect rainwater. These pretensioned precast concrete tubs have the important job of catching and draining water collected from nearly 10 acres of roof area. To prevent a cascade of water from pouring into the stadium, a temporary enclosure was built above the gutter to divert it and provide a dry workspace. This enclosure, designed for full hurricane force winds, was supported by wide flange steel framing that can be disassembled and reused for the opposite elevator shaft, during the following offseason construction.

Erecting the enclosure structure was perhaps more difficult than the permanent elevator overrun structure itself. Thanks to the creative steel erector and careful planning and coordination, a scheme was devised to use spliced members that were small enough be lifted to the top of the seating bowl, into the press box, and through a hole in the gutter wall using a series of splayed cable winches guyed off the roof trusses. Once in the gutter, a cable-stayed steel mast supported a cable and trolley that carried the steel into place. After completion of the temporary enclosure, the existing gutter tub was demolished, steel overrun framing installed—respecting the dome roof movement joints—and new cast-in-place gutter tubs were built. Then, the temporary enclosure was disassembled and rebuilt for the elevator at the opposite end of the press box.

The capital improvements at the Caesars Superdome were gradually rolled out to Saints fans after each phase of construction and when the completed project was unveiled to the world at the hosting of the eighth Super Bowl this past February. The stadium, now equipped with modern amenities and improved accessibility, is poised to welcome a new generation of fans, ensuring its legacy continues for years to come. ■