The deck-assembly system Tacoma Narrows Constructors is using on the new bridge is as technically advanced as any ever tried.
But the basic concept is not new. In 1940, bridge builders hoisted the deck onto Galloping Gertie in much the same way. The main difference was that the deck sections on the old bridge were much smaller.
The deck was two lanes wide and had no stiffening trusses beneath it. Each section was just 8 feet high and 50 feet long. Each weighed about 40 tons, a fraction of the new deck sections, which weigh between 260 and 504 tons each.
Also, there were no gantry cranes. Deck sections were barged into position under the bridge and hooked to cables powered by engines at the bases of the towers.
The first lift, on the morning of March 21, 1940, did not go as planned.
The first section was to be lifted to the center of the main span, and engineers underestimated the strength of the current.
A long, frustrating attempt to hook up the cables on an incoming tide failed, nearly capsizing the Foss tugboat Tango in the process.
The second attempt, during the slack tide that afternoon, was captured this way by Tacoma Times maritime columnist Casey Davison:
“The tugs heaved together and in opposite directions; they rolled on their beam’s (sic) ends and they roiled the water to a foaming wake; they’d fight the sluggishness of the scow in the current and then they’d fight the maddening momentum which made the scow overshoot her inch-precise mark. Thus they spent a spectacular hour at cramped maneuver.”
At last, Davison reported, the tugs managed to hold the barge in position long enough to get the cables attached.
But when the cables took the weight, the barge and the deck section lurched away from each other. Three men slammed themselves on the barge deck to avoid being swept overboard or crushed. Several others leaped onto the suspended deck and were left hanging there until the Tango returned to rescue them.
The crews quickly got the gist of it, though, and in just 45 days, they had all but the last section in place.
Unfortunately, the last one was too big to fit into the gap that remained.
According to Joe Gotchy, who worked on the bridge and wrote about it in his book, “Bridging the Narrows,” crews tried forcing the piece several times without success. At last, at the suggestion of an assistant superintendent, they packed the section in dry ice overnight to cool and contract the steel. In the morning, it fit perfectly.
Builders of Gertie’s replacement – the bridge currently in use – employed a different, more dangerous deck-building technique.
That time, the deck was lifted up not in prefabricated sections but in individual pieces, like Tinker Toys, to be assembled in midair.
While the beams dangled from cables, ironworkers fastened them together by crawling out onto them and hammering bolts into predrilled holes.
“We started out at the towers and went both ways,” said Earl White, an ironworker who helped build the bridge. “We had to do it like that to keep the towers in balance. If we put so much tonnage in midspan, we had to add that much on the other side.”
White, now 85 and retired in Tacoma, was on the east midspan gang, the crew assigned to build the section of deck stretching from the Tacoma tower to the middle of the bridge.
He was what was called a bell puncher, there to guide the hoist operator. The hoist operator was situated where he couldn’t see what he was doing, so White gave him directions with a system of lights.
“I gave him signals for ‘Boom up;’ ‘Swing over;’ ‘Drop load’ and so forth,” White said. “We had it down pat.”
When enough of the deck was in place, the workers put temporary railroad rails on its top and hauled the steel from the towers to the ends of the deck on rail cars.
“They were nice little railroads,” White said. “You’d probably get a laugh out of them if you saw them today, but they really did their job. As we went, they kept on adding track to the railroad.”
At the ends of the decks, ironworkers wrestled the steel into place and fastened them with temporary pins and bolts.
“The guys worked with big old beaters, snorting as they swung,” White remembered. “They’d get about 25 percent bolts, then when the riveting gang got there they’d knock out the bolts and put in rivets.”
Although they were working 200 feet over the water, the men used no safety lines.
“We had 12-foot lines coiled on our belts,” White said, “but I never saw anybody use them. Nobody bothered.”
The ropes got in the way, White said, but more than that was the thought of how far a person was likely to be able to swim when tied to a steel beam that might fall, taking the worker with it.
“Nobody wanted to be tied off to something they couldn’t get away from in a hurry,” he said. “If you can move, you have a fighting chance. If you’re tied on, you’re done for.”
Two ironworkers fell into the Narrows and died while building the deck. One was White’s close friend Whitey Davis, who missed when he tried to step onto the lower ledge of an 8-inch-wide I-beam. White vividly remembers the sight of his friend disappearing into the water below, dragged under by his heavy tool belt.
“I thought I saw him move a little bit,” he said, “but I couldn’t be sure.”
The deck was pieced together by four gangs working in different directions, White said, giving workers themselves some doubts about whether the ends would match up.
“We were a bunch of old hardheaded ironworkers,” he said. “We just couldn’t see how it was going to come together in the middle. But those engineers had it figured out right to the gnat’s eyebrow. That last piece just fit in there perfectly.”
White is watching construction on the new bridge with great interest, and he looks forward to seeing how the new deck assembly system works.
“I think it’s going to be fabulous,” he said. “It’s going to be something. I sure envy those guys working out there.”
White said he takes every opportunity to visit the construction site and talk to young ironworkers.
“Kind of like an old fireman going to the fire, I guess,” he said.
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