[TowerTalk] Tower Collapse in South Dakota

[Joseph B. Fitzgerald]

Interesting.  I had a notion that lattice towers fail due to exceeding the bending moment of the lower part of the structure trying to accelerate the upper portion too fast ... this is classic phenomenon in smokestack demolition.

Take a look at this video of a 480 foot tower with a pier pin in West Virginia that had to come down.

https://www.youtube.com/watch?v=yKQ0p5L_qvU

BTW that tower had to come down because water collected inside the tower legs, froze and split the tubes.  Check your weep holes each year before the first frost is forecast!!!

I suspect the South Dakota tower was simply built unusually well and could deal with the bending moment, while the West Virginia tower was not and buckled.  

de KM1P Joe