Tiedown tension vs az,za and temp.

Links to plots:
the total tiedown tension vs temperature (.ps) (.pdf):
the td tension by corner  vs za, az, and temperature (.ps) (.pdf):

 
   The tiedown tension model generated from the 2008,2009 tiedown data was used to plot the tensions vs az,za and temperature. The parameters used were:

• The carriage house is at  stow 8.83 degrees.
• The tensions are to keep the platform in focus (1256.22 feet).

• The red cross is the prestress tension that the ammann & whitney drawings say should be in the tiedowns at 90 F (24Kips*6 cables). We don't reach that value until 70F.

• Plots were made for 70F, 80F,85F, and 90F
• At each temp, plots were made vs za and vs az.
• Page 1,2: 70F
• page1: tension vs za.
  
• The 5 frames show az = -60,-30,0,30,60 (with the 2.87 degree tower offset).
• Page2: tension vs Az
• The 5 Frames show za=1.1,5,10,15, and 19.7 degrees za.
• The other pages are for the higher temps.

summary:

• At 90 F the total td kips on the platform is 98Kips this is 46 kips less than the 144 kips that the drawing  described.
• When the dome is at 19.7 degrees and the ch is at  stow, we can lose tension in a tiedown when the temperature goes above 75F.
  

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