Monday, June 28, 2010

CRANE EXITS STAGE EAST

Throughout the entire Quarry Visitor Center rehab project, one part was always seen as a looming menace and universally recognized as the greatest threat to the fossils. That component was getting the crane out of the Visitor Center without damaging the bones. Given its weight, removing the crane was a challenge. And there really weren’t too many options.

The first was to take it apart, either cutting it up or disassembling it, inside the Visitor Center. This was fraught with problems. How would one hold up the entire crane while pieces were removed and how would the pieces taken off be moved and taken out of the building? Space inside the QVC is limited and there is not sufficient space to have multiple large pieces of equipment inside the building holding and moving heavy pieces of the crane. Dropping a bolt from the crane would be bad enough, but dropping a separated subunit of the crane would be catastrophic.

The alternative was to take the crane out of the building intact and take it apart in the parking lot. Fortunately, the plans for rehabing the QVC included replacing the glass walls. Of particular relevance to the crane problem was the multitude of problems involving the east wall of windows. The most serious of the problems was that it had pulled off the foundation and was hanging by the welds to the roof beams. Repairing that problem required removing all of the glass on the east wall as well as the window framing and I-beams. So the entire glass wall would at some point be gone. That gave an opening for getting the crane out.

Eventually the plan developed was to extend the track railing on the floor outside the building and into the parking lot. Two large cranes, each with a lift capacity of 50,000 pounds, would attach chains to the crane and slowly pull it out. Once out far enough that it was beyond the overhang of the roof, the crane could be lifted up and moved.

In the end, the pull went smoothly and only took about an hour to complete. Nevertheless, everyone breathed easier once it was finished. With the crane safely out of the building the most dangerous part of the QVC project (at least to the fossils) was over with. It was a great show and I was glad to be able to see it.

Photos courtesy of Dinosaur National Monument.

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