Scanning the towers after the collapse

17dec20


Intro:

    The p50 laser scanner was used to scan the sides of the towers to see if they are still vertical after the platform collapse.
Timeline:

The tower configuration was/is:


 Labeling the faces of the towers:
   
When the p50 looks perpendicular to a tower face, it will see 3 flat faces.

The image below labels these faces:

planview

Each color shows the 3 faces that are visible when looking perpendicular to a face.


Processing the point cloud.

    The steps taken to process the point cloud were:

Table of tower scans:

tower
date
face
.las file
link to writeup
p5 location
Notes
plots
12
201209
1
.las
201209
visitor center balcony
After collapse
.ps  .pdf

200904
1
.las 201209
eastSide rim roade
after aux4North
failure
.ps  .pdf

201223
3
.las 201223
road next to Visitor center
after collapse
.ps  .pdf

201124
3
.las 201223
road next to visitor center
after aux4N and T4M4
failure
.ps  .pdf
4
201228
2
2L
2R
.las 201228
southeast side of helipad
after collapse
.ps  .pdf
.ps  .pdf
.ps  .pdf

200915
2
2L

.las 201228
southeast side of helipad
pre collapse
.ps  .pdf
.ps  .pdf
8
201111
1
1l
.las
201111
west side of helipad
pre collapse
.ps  .pdf
.ps  .pdf



Tower 12

09dec20: T12 (face 1) scan south looking face from vc balcony

    The scanner was located on the visitor center balcony looking north to the southern face of T12.

 We compared these results with data taken 04sep20 before the collapse


    After rotation the coordinate system was:

The first plots shows the scanned data results for 9dec20 (.ps) (.pdf)

The 2nd plot shows the scan of the T12 southern face on 04sep20 (pre collapse) (.ps) (.pdf)

09dec20 Summary:

processing: x101/p50/towers/t12/f1south/getdata_20xxxx.pro, plotit_20xxxx.pro

23dec20:T12 North looking face (face 3)

    Data was taken from the road next to the visitor center. The same location was used on 24nov20 prior to the collapse (the 24nov20  spot was about 20 feet farther away).
The plots show the results of the measurements:

The results are similar to the south looking face. There is an unwinding of the tower after the collapse.

processing:x101/p50/towers/t12/f3north/getdata_20xxxx.pro, plotit_20xxxx.pro


Tower 4

28dec20: T4 face 2 from SE side of helipad

    Data was taken from the se side of the helipad looking toward tower 4 (face 2 facing NE).



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