IT Lab   About Frank   ·  About IT   ·  Ravenel Bridge  ·  Unbuilding Bridges  ·  Photo Essays   ·  Forgetting
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.

Buy Sparky's History of the Unbuilding of the Grace and Pearman Bridges


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)

November 30, 2005:
Imploding Pearman Pier D-25

It was a long long day - starting about 6:30 this morning - a day to watch the loading of D-25 and the implosion. After putting this together, I visited Google using dynamite sequence control - and found two really good tutorials.

Learning Links

We made several video options revealing the dynamics of today's implosion of D-25:

What was remarkable to me was how the sequencing of the detonation was controlled. Watch how Mickey's team loaded and fused the explosives. Here is the implosion sequence from still photos and from frames of the video.

t = 15:53:08

Here you can see the detonation sequence progressing upward - t = 15:53:09

I extracted each individual fram from the video (30 frames/sec) in order to explore the individual ignitions - as shown below. Every frame is not shown - but I have indicated the time of each frame assuming 30 frames/sec. The bright (sort of) dots and lines are the individual ignition events - better seen in the shadow portion of the two columns.

t = 0, 0.033, 0.067

t = 0.100, 0.133, 0.233

t = 0.367, 0.533, 0.600

t = 0.633, 0.700, 0.733

t = 0.800, 0.867, 0.900

t = 0.933, 0.967, 1.000

t = 1.033, 1.067, 1.100

t = 1.133, 1.200, 1.233

At this point, the lower 300 ms delays have kicked in and the base starts to ignite - looking like the upward directed base dynamite ignition is chasing the upward directed fuse ignition.

t = 1.267, 1.333, 1.367

t = 1.400, 1.433, 1.467

t = 1.500, 1.600, 1.633

t = 1.667, 1.700. 1.733

t = 1.767, 1.800, 1.833

t = 1.967, 2.100, 2.633

and here the cap ignites

t = 2.700, 2.733, 2.800

Here you note almost no vertical component of the blast - t = 15:53:09+

t = 15:53:10

t = 15:53:11

t = 15:53:12

t = 15:53:28

t = 15:57:49

With Cousin Arthur smiling his approval - all that remains is the lower support - which will be the target of a separate preparation and detonation.

And of course - transport courtesy of Sharon.

and a view of the Ravenel Bridge without D-25 in the background

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 http://oldcooperriverbridge.org