This old building will survive the Big One
Thursday, May 10, 2007
Fred Leeson
The Oregonian
Engineers and architects gave no thought to earthquakes when they built Portland's new Fire Station 1 in 1952.
If they had, perhaps they wouldn't have chosen the site at 55 S.W. Ash St. In those days, "people were aware that earthquakes happened in California, but not in Oregon," says Kent Yu, a Portland structural engineer. "In the past 20 years, we've started to realize that's not true."
Yu, who earned his doctorate in the heart of California earthquake country, will determine in coming months how to brace Fire Station 1 so it not only could survive the Big One but also provide emergency services immediately after.
City officials originally planned to build a new fire station and administrative headquarters a couple of blocks north of the station. But when cost estimates exceeded the budget, they decided to revamp the old building. It is home to 16 emergency-response personnel and about 68 administrators.
Issues with the 55-year-old building include its structure and the ground it sits on. Moist, soft soil that ranges from 17 to 31 feet below the building could turn to liquid if firmer ground below started to shake. Experts call it a liquefaction zone.
"One of our main concerns is liquefaction settlement in the basement," says Yu, associate principal of Degenkolb Engineers in Portland. Techniques for stabilizing the soil below will be part of the solution.
Above ground, the goal is to brace the building so it's emergency-ready after a once-in-500-years quake and still standing after a once-in-2,500-years quake.
Alas, some of the original construction documents no longer exist. "Lots of critical details are missing," Yu says. So like a doctor examining a patient, he says, "we'll run a bunch of tests on materials to get the best information we can about its condition. Once we know everything, or the most we can, we can make reasonable decisions on a rehabilitation scheme."
Fire Marshal John Klum says the Degenkolb firm was selected because of its creative solutions in retrofitting buildings. Earthquake bracing is expected to be the costliest item in a $9.5 million construction budget.
Money for the project comes from a 1998 bond approved by voters to upgrade or relocate about 30 Fire Bureau buildings. Other elements in the Fire Station 1 plan include meeting physical disability standards, separating dorms for men and women firefighters, and upgrading administrative offices.
Until earthquake bracing costs are determined, "how far we can get on the tenant improvements, we just don't know yet," Klum says.
Yu, working with Peck Smiley Ettlin Architects, plans to finish construction plans early next year. Klum says emergency-response teams will be relocated in mid-2008. Renovation is expected to take 12 to 16 months, depending on the budget.
When the work is finished, most residents won't notice any difference from the outside of the three-story brick building.
"We are treating it like a historic building, which it is," Yu says. "We will try to maintain the historic look of it."
Fred Leeson: 503-294-5946;
fredleeson@news.oregonian.com
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