Tuesday, February 8, 2011


 One of the best known architectural elements of the previous Quarry Visitor Center was the snake-like entrance ramp running from the parking lot, sensuously wrapping itself along the outside of the Rotunda, and providing an entrance to the second floor of the building. This was a clever design for when entering the building the visitor was struck dumb by the spectacular overview of the entire cliff face. It was a great piece of drama and quite effective. Visitors came expecting to see mounted skeletons and instead were confronted by a vision that both awed and raised questions as to how this mass of bones come to be.

Being built in 1958, the ramp predated handicap access issues and code. That is plainly seen in photos of the original ramp, which shows a short series of steps at its base. At some later date the stairs were removed and the bottom of the ramp sloped. To visitors the ramp was deceptive. It appeared to be handicap access but the slope was much too steep and unsafe for wheelchairs.

With the design of the new QVC we wanted to retain that original majestic entrance and introduction to the cliff. But with no Rotunda to wrap around, a different solution was needed. The new design calls for a long ramp running along the south side of the building, with one switchback, to bring it to the second floor. While the ramp seems long, it is well within requirements for handicap access.

After the concrete south wall was poured and completed, its foundation was still exposed in a deep trench well below ground level. So the first step was to fill in the trench and then slope it up to the south wall. The soil fill needed to be solid, so after filling the trench the soil was compacted.

One tool was the standard handheld powered compactor. That’s a pretty jarring piece of equipment to use, but it allows one to work right up to the foundation.

A second piece of equipment was a larger, more powerful, remotely controlled compactor that was run by an operator using a control box with a joystick. This machine moved back and forth, compacting wider swaths of the soil.

With the soil compacted ramp construction could begin. The components were brought to the site. At present the frame of the upper part of the ramp has been built, installed on the footings, and welded into place. The lower part will be installed later in construction, as vehicles are still driving and working over the spot where that ramp segment will go.

Yes, I realize that this is a ramp and not a stairway, but given the opacity of Led Zeppelin’s song lyrics, I feel my title is not too much of a stretch.

Photos: NPS

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