A construction crew will demolish the remainder of Gilbert Hall’s Commonwealth Bridge on Monday in the most recent phase of a $40 million project to remodel and build a four-story addition to the business school.
Crew members of Lease Crutcher Lewis company tore down about 6,000 tons of concrete, steel and brick from the east side of the Commonwealth Bridge early this week as many passersby looked on. A 140-ton trackhoe with a mechanical claw and a “thumb” ripped out steel bars from inside the concrete walls and brought them crashing to the ground. Workers sprayed sections of the walls with water to quell dust.
Workers used the trackhoes to separate the rubble into piles Thursday so drivers could move the materials to Delta Sand & Gravel. Large heaps of discarded rebar, brick and steel trusses sat on the grass on the site’s south end by 13th Avenue. Crew members said nearly all of the materials will be reused.

“A lot of it goes to roads,” said Matt Pearson, project manager for Lease Crutcher Lewis. “They’ll grind up the concrete for base rock.”
Rexius Forest By-Products Inc. workers used a powerful air hose to cover roots of the trees west of Deady Hall with an organic compost.
Larry Bolan, who’s been with the Eugene-based company since 1977, said the area’s irrigation system will remain shut off during construction. He said the compost, made from yard refuse, would help the trees retain precious water in the event of another dry summer. Bolan said the company will eventually lay the equivalent of about three football fields of mulch 4 inches thick.
Pearson said crews should begin excavating the basement in two weeks, after demolishing the remainder of the bridge. In the fall, the team will use a 211-foot tall crane to erect the building’s steel and concrete frame.

Onlookers gathered each day this week to watch the demolition, including architecture graduate student Jess Ellingson.
As crews exposed the skeleton of the bridge, Ellingson said she picked up many valuable lessons for an aspiring architect.
“I can see what the fate of one of my buildings might be,” she said. “The construction system of reinforced concrete doesn’t allow the building to adapt to future uses.”
Contractors used concrete for the building’s lateral bracing instead of a system of steel supports, Ellingson said. Steel-brace systems can be more easily adapted to meet structural changes, such as adding useable space to a building.
Wick and Hilgers originally built the bridge in the 1950s at a time when contractors were using more open-web steel joists as cheap replacements for standard beams, architecture professor Don Peting said. Contractors ordered steel joists with specific, unchanging dimensions.
“They couldn’t be extended or anything like that,” he said.
Ironically, the removal of the Commonwealth Bridge brings the University’s design more in line with what the school’s first architecture dean had in mind, Peting said. Ellis Fuller Lawrence, who served as dean from 1914 until his death in 1946, wanted to create a clear line of sight from Knight Library to the fence lining 11th Avenue — Dad’s Gate.
The Lillis Business Complex will be completed for the 2003-04 school year. The project will add 600 classroom seats and numerous media resources.