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John Larkin[_3_] John Larkin[_3_] is offline
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Default Treehouse bridge update: one section blew down in the California storms

On Wed, 31 Dec 2014 09:23:38 +0000 (UTC), "Danny D."
wrote:

The third section blew down in the California storms.
https://c4.staticflickr.com/8/7511/1...6a237edc_c.jpg

It was just the frame, and a few deck timbers:
https://c4.staticflickr.com/8/7478/1...ec573ed9_c.jpg

Apparently the mistake was to attach it here to the redwood:
https://c4.staticflickr.com/8/7515/1...3135617f_c.jpg

These two smaller redwoods apparently bowed to the sides:
https://c4.staticflickr.com/8/7541/1...27bc211f_c.jpg

We had only the far end attached to the steel cable:
https://c1.staticflickr.com/9/8658/1...9ac90178_c.jpg

So, we think the mistake was to trust the redwoods and not attach
the close end to the overhead steel cable, and also that we had
attached the far ends to the cable temporarily with just rope,
which broke when the redwoods splayed out in the winds.

What we think happened was:
1. The redwoods splayed outward, pulling the boards out.
2. The close end fell downward putting pressure on the far end.
3. The rope on the right side of the far end broke under stress
tumbling the boards to the steep hillside below:
https://c4.staticflickr.com/8/7478/1...ec573ed9_c.jpg

We still can't get the dog out onto the bridge yet, though:
https://c4.staticflickr.com/8/7536/1...5aedd4e3_b.jpg



The winds were vicious yeaterday. Driving back to SF, somewhere around
Vallejo, a huge multi-trunk tree blew onto I80 and blocked traffic for
miles. Westbound, traffic was blocked by the trees, and eastbound, it
was blocked by idiots.

http://www.sfgate.com/bayarea/articl...RT-5985826.php


Here's The Brat, the kid what does our PCB layouts.

https://dl.dropboxusercontent.com/u/...ee/TheBrat.jpg

The wind chill up there was in single digits up there on Monday, and
predicted -20F in places on Tuesday night. They can get 100 MPH gusts
up there on the peaks. Sunny California.


--

John Larkin Highland Technology, Inc
picosecond timing laser drivers and controllers

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com