Since 1996 Structural Design, Inc. has used a number of installations of Multiframe on a wide variety of design projects. One of their most interesting examples is a stadium upgrade for the University of Michigan. In response to increased demand for stadium seating in the fall of 1997, they embarked on a plan to add 5000 seats to their stadium, as well as scoreboards, in time for use during the 1998 fall season.

As originally designed in 1926, the stadium was a fully below grade, cast-in-place concrete bowl. Over the years, steel bleacher additions, most notably in 1949, added a ring of above grade seating around the bowl. The challenges presented to the architect were: first, to extend that ring of steel in a way that would visually unify the stadium perimeter and conform to modern codes, and second, to envision the project in such a way that it could be both designed and constructed in just ten months.

A steel perimeter truss was designed to serve several purposes: support gravity loads of the new seating above, resist dynamic lateral loads prescribed by modern codes for stadium seating, accommodate the complex geometry and circulation patterns already developed by previous expansions, and finally to provide a rich visual background for the bold graphic facade treatment designed to wrap the stadium perimeter.

The structural portion of the upgrade was modeled and analyzed using Multiframe while the Steel Designer module was used to assist with the steel design checking. Section Maker was also used to model and calculate the section properties of the numerous custom shapes used in the structure.

Photos courtesy Joseph Arcure/Paul Dannels.