UKTC Archive

Re: Cavity treatment - gab ions

Subject: Re: Cavity treatment - gab ions
From: guy Meilleur
Date: Mar 06 2012 01:50:29
 
"Guy, it's some years since I read To Kill a Mockingbird, and I'm not sure 
that the "cavity-phobia" made it into the (superb) James Stewart (IIRC) 
film, so just remind me, if it's not too much trouble."

Bill, Boo Radley was a "special" neighbor to Peck/Peccary and his kids.  
Boo left his carvings and other objects for the kids to find, in a cavity 
in his front yard tree.  Very touching exchanges took place, until Boo's 
old man found out.  Ashamed of his son's specialness, he concreted the 
cavity, to end the interaction.  I never read the book--saw the movie when 
it came out though, by myself, 10 years old, in a theater 2 miles from 
home.  Longest walk/run of my life--the Radleys were behind every tree.
"To be fair to Scott, I don't think he was suggesting that filling a cavity 
was a good thing in a cavity-phobic sense, but rather as a method to 
specifically prevent failure through cross-sectional flattening. I 
suggested that although relevant in theory, the actual change in 
cross-sectional shape before critical values for material failure are 
reached is likely to be very small, such that constructing something that 
would have a beneficial effect would not be likely to be feasible."

Paul, I know Scott to be far too rational to fall prey to caviphobia, and I 
would still invite anyone with experience showing that cavity filling leant 
support to submit that experience to the A300 committee.  The BS does a nice 
job describing angles of the guys, but its "should consult with an engineer" 
is not all that useful ime.  And I would question the notion that arborists 
are not structural engineers--we engineer tree structures every day, 
especially those who are up in the tree doing the work.

I share your skepticism about the potential for gabions to be effective, but 
no one *knows*.  
Just because we lack those letters after our names does not mean that our 
experience and good standards cannot guide us to installing  effective 
supplemental support systems.  The last ANSI meeting took in a testing lab, 
where we saw a 15,000 lb. test cable break, while the Wedge-Grip end 
fasteners held.  Made me feel better about using that technology--seeing is 
believing, and knowledge is power--doo dah, doo dah.




-- 
The UK Tree Care mailing list
To unsubscribe send mailto:uktc-unsubscribe@xxxxxx.tree-care.info

The UKTC is supported by The Arbor Centre
http://www.arborcentre.co.uk/