Abstract:
Dan Brown and Associates (DBA) teamed with Richard Goettle, Inc. (Goettle) to design the permanent retaining walls for the new Columbus Crew Major League Soccer (MLS) stadium. This presentation will focus on the design and challenges associated with the perimeter secant pile wall and anchored soldier pile tunnel entrance wall.
Lower.com Field is located near the confluence of two rivers and the stadium includes a recessed playing field (pitch) and lower stadium seating below the floodplain elevation. DBA designed the perimeter secant pile wall for temporary and permanent earth retention to establish field and service level elevations and for groundwater cutoff. The secant pile wall design incorporates cantilever heights of 24 feet, shallow groundwater, and rigorous deflection limits. The secant piles are comprised of interlocking 46.5 in diameter piles with alternating piles reinforced with W36x210 steel beams. Primary, unreinforced piles were constructed using continuous flight auger drilling methods and secondary, reinforced piles were installed using drilled shaft techniques with sectional casing.
A pitch access tunnel provides vehicle access to the field under the main concourse. DBA designed anchored soldier pile walls that form the access tunnel walls and extend in two directions from the tunnel along the perimeter of the stadium to form the tunnel entrance walls. The tunnel and tunnel entrance wall designs include maximum wall heights of 23 feet between the concourse and pitch elevations. Additionally, the tunnel retaining walls provide permanent vertical support for the concourse-level slabs, columns, and parapet walls. The design incorporates post-tensioned tieback anchors installed through the soldier pile beams. Anchors were located and installed in close proximity to foundation piles and overlapping anchor locations, which required special consideration and control though the design and construction phases to ensure successful completion of the tunnel walls.