Changing the face of Charleston : The unbuilding of the Grace and Pearman Bridges
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(Apr 10)
Meeting St. Stories
(Jul 10 2006)
East Bay Stories
(Oct 10 2006)
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(Feb 17)
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(Apr 3)
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(Apr 3)
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(Mar 27)
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(Mar 13)
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(Feb 28)

October 5, 2005:
Dropping a Pearman Support Column

Sort of like dropping a tree. You tie a rope near the top, notch the bottom and then pull the tree top with the rope while a brave soul cuts away at the opposite side of the tree. Here instead of a rope, there is a cable, instead of someone pulling the rope, there is a CAT and instead of cutting away at the opposite side of the tree with an ax - small explosive charges are placed near the bottom of the column.

Click for a composite video of the falling column

Here is the before. Click on the image and you can see the cable looped around the cap.

On the left you can see the cable looped around the cap, in the middle, the grapple that will tension the cable and on the right, the grapple in its final position. (Click on the image for a larger view)

On the left, the cable is tight but in the middle, the cable broke and as luck would have it, you can see the wiggles in the cable as it recoils. On the right - a limp cable, waiting for repair. Click the image for more detail.

Here are the guys investigating the end

making a new loop

and then the cable is pulled tight - final inspection of the site.

and the charge is triggered (left) and you can watch the column fall forward - just like dropping a tree

a little bit further

and a bit further

until its down and the dust begins to settle

Here is final resting place until it is broken up

and a different view

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Attribution: C. Frank Starmer and Sparky Witte from