Project Highlights

• On-site representative for structural engineer of record
• Steel connection design
• Structural support of plaza and auxiliary structures

Overview

MBJ provided plan review and on-site representation for structural engineer of record Walter P. Moore on the Minnesota Twins ball park. In addition, MBJ designed steel connections for the stadium, as well as providing structural engineering for related pedestrian plaza structures, which included the following:

The 6th Street pedestrian bridge is a 310 foot long (7,500 square foot) elevated walkway connecting 1st Avenue North and the elevated ballpark plaza in downtown Minneapolis. The structure was built below the existing Target Center structure, around existing building columns and used cantilevered construction to minimize the footprint at grade. The structural system consisted of reinforced concrete deck with unbonded topping, structural steel framing, reinforced concrete columns, grade beams and pile caps supported by helical anchors.

The Skyway Stair on the pedestrian plaza is designed with structural steel stringers supporting cast-in-place reinforced concrete on the stair and landing. Design included reinforced concrete walls and planters. Base support and reactions were coordinated with the bridge Engineer of Record (URS). Design and detailing was coordinated with the ballpark architect (Populous). The existing skyway was modeled to analyze capacity of existing structure to support additional loading.

The Gate Canopy is a cantilevered structural steel canopy and gate structure built on top of an existing bridge structure. Base support and reactions were coordinated with the bridge Engineer of Record (URS). Design and detailing was coordinated with the ballpark architect (Populous).

Foundation design for various plaza elements included base support and reactions coordinated with the bridge Engineer of Record (URS). Design and detailing of the various foundation structures was coordinated with the Landscape Architect (Oslund and Associates). Supported structures included a 40-foot bat-shaped topiary, statuary, signage, and canopy structures designed by others.

An existing 90-foot tall flagpole from the original metropolitan stadium had been salvaged by a local VFW post. The VFW agreed to donate the historic flagpole to the new ballpark if a new flagpole was provided in its place. MBJ designed and detailed a retrofit base-plate for the existing flagpole, coordinated structural loading with the bridge Engineer of Record (URS) and provided minimum acceptance criteria for the testing agency to verify.