Changing the face of Charleston : The unbuilding of the Grace and Pearman Bridges
Frank's Internet Home Page
Blog: 2005
Archives of unbuilding sections
Blog: 2006
The story of building the Ravenel Bridge
Visit our
Adventures in Singapore
Click to view all web page segments
I enjoy hearing from you. If you have comments and suggestions, write me.

Unbuilding Highlights
(Apr 10)
Meeting St. Stories
(Jul 10 2006)
East Bay Stories
(Oct 10 2006)
Drum Island Stories
(Feb 17)
Pearman Bridge Stories
(Apr 3)
Grace Bridge Stories
(Apr 3)
Imposions: Prep and boom
(Mar 27)
Unbuilding Bridge Blog
(July 23 2006)
Unbuilding Challenges
(Mar 13)
Learning Links
(Feb 20)
Unbuilding Stories
(Mar 13)
Video and Sounds
(Feb 28)

January 9, 2006:
An early start, loading, imploding Pearman D-24 pier and making our way back home. Morning sun is wonderful, warm and golden. It is my favorite time for capturing what happens around us.

Early morning - and the trip out to D-24.

and Toby taking us to the worksite - always smiling

Ken is the boss today - Mickey had a fight with his appendix and the docs at East Cooper run

Early morning view of the Ravenel Bridge - golden sun

Before - and Toby - looking over Toby's shoulder. D-23 is over his shoulder. Today's job is to drop D-24 - to the right of the Ravenel support column and near the end of the Grace ramp.

An early morning look east - the D-25 stump and cousin Arthur looking on

and an early morning seagull keeps us company

and Sonny Miller is waiting in his crane to do the vertical fetching and toting.

Here is the horizontal fetching and toting - Ken (in the cage), Phillip, Bret and Toby

Our team: Sonny playing the crane, while Phillip, Ken and Bret play the dynamite - loading the basket for loading D-24

Ken and Phillip, with their protective purple gloves and ready to go

Ken and Phillip loading. The nearer column has been loaded and you can see the faint outline of the fuse lines. Here they are working down from the top of the far column.

Here, Phillip loads a stick of dynamite while in the foreground are the hanging fuse lines from the nearer column.

a closer look - Phillip loads a stemming bag while Ken tamps it into place.

and when all the loading is complete - here is the shock tub3 detonator array. If you have your curious eyes switched on, you might ask why some holes have a cross and other holes have an X. The X holes are incomplete. While drilling, rebar was encountered so that the hole position had to be shifted to one side or the other. The X was painted so that the correct holes would be loaded. Nice piece of documentation.

When all loading is finished, a friendly tug moves our barge.

Looking toward Drum island, you can see the tug pushing our barge as viewed from under the west Ravenel diamond

Meanwhile, on the Grace Bridge, Pio, Richie, Steve and Roy are cutting and removing more roadway.

and if you look closely, you'll see Roy in his cab and Pio in the mega-fork lift to the right.

While on the Pearman approach you can see the outline of the foundation for the Mt. Pleasant observation pier

and a closer look at Bob, Jack, Chris and Michael working on the last Pearman approach piers. In the foreground are the stumps of M1 - M5 and in the background are the support that are in shallow water - requiring a different strategy for preparation.

As the clock kept ticking - the 3pm magic moment approache. 3 toots for a 5 min warning, 2 toots for a 1 min warning , the "fire in the hole" - the blast and 1 toot for all clear. Just like clockwork.

Click for implosion video (1 Mb mpg)


This ignition sequence (stills extracted from the video)

T = 0 ms

T = 33 ms

T = 67 ms

T = 100 ms

T = 133 ms

T = 167 ms

T = 200 ms

T = 233 ms

T = 267 ms

T = 300 ms

T = 333 ms

T = 367 ms - detonation just above the base

T = 400 ms - necklace propagation at the pier cap

T = 433 ms

This set of blast photos were an experiment. To see the fuse ignition, the backup needs to be in a shadow. But with a slower shutter speed because of the darker subject, there is a bit of motion blurring. Here you can see the detonation at the base and fuse ignition at the top - like necklaces around each column. So our experiment was a partial success.

Finished - no more D-24 and another clean implosion

A few pieces of residual rebar - to be recycled

Another view

For comparison: Before in the early morning

and after: about 3:30 pm

Click to view all unbuilding web page segments

Creative Commons License
This work is licensed under a Creative Commons License.

Attribution: C. Frank Starmer and Sparky Witte from