October 6, 2006 Volume 107 Number 19
Crew at Thompson Metal Fab kept tram construction on scheduleMonths before the Portland Aerial Tram became visible from Interstate 5, a 100-person crew in Vancouver, Wash., was working around the clock fabricating the steel components for the upper station tower at Oregon Health and Science University and the intermediate tower located off SW Macadam Ave., in Portland.
That work crew represented some of the finest craftsmen and women at Sheet Metal Workers Local 16 — all of them employees at Thompson Metal Fab Inc.
Thompson played a somewhat unusual role as general contractor for both the fabrication and erection work. The company subcontracted the actual building of the towers to Carr Construction. (An article featuring the topping out of the upper station tower by members of Iron Workers Local 29 at Carr Construction was featured in the Sept. 15 issue of the NW Labor Press.)
“For the most part, fabrication went very well. Our guys did an outstanding job. There were very few glitches,” said John Rudi, president of Thompson Metal.
Design changes and coordination problems early on had put the tram project five weeks behind schedule. Once those issues were worked out, Thompson’s crew was able to make up ground so that by the time the upper station was topped out on Aug. 31, it was back on schedule for a tentative opening on Dec. 15.
The 196-foot intermediate tower (pictured above left) was built in three pieces — each with a complex series of welding challenges — the largest of which was the foot, measuring 90 feet long by 33 feet wide at the bottom and weighing 130 tons. As the Daily Journal of Commerce noted, “The tower was built of five-eighths-inch plate steel with T-stiffeners attached inside to resist the heavy twisting loads that the tram will exert. Full penetration welds were used wherever the pieces of steel were spliced together.”
The upper station tower (pictured above) was even more complex, featuring four tiers and a steel superstructure on top. The footing required 78 drilled shafts averaging 70 feet long each and 1,500 cubic yards of concrete.
“It was a difficult fabrication project,” Rudi told the NW Labor Press. “It was very thick steel with a lot of heat input. It required a lot of skill to hold the tolerances. There wasn’t a lot of room to make adjustments in the field. Our guys had to make it right in the shop.”
Curtis Anderson, field operations manager for Carr Construction, said the intermediate tower had to be within one inch of plumb. “We came in at a quarter-inch. I can’t say enough good things about the fabrication work.”
Mike Mayes, president of Mayes Testing Engineers, told the DJC that the tram project is one that “people swell up with pride thinking they were even involved. Portland doesn’t have an icon. I think this is going to be it.”
© Oregon Labor Press Publishing Co. Inc.