Zugdreieck

12:48 Feb 12, 2009 

If you can take liberties with the text, it might be better for English-speaking readers to turn this around and deal directly with the concepts of tensile force and stress. The flared shape of the base of a tree trunk is a direct result of stress in the growing tissue: the tree responds to stress by forming more tissue in stressed areas (if it didn't, branches would break off from their own weight or the trunk would snap off at the base in the first storm). The same phenomenon occurs in growing bones.

12:44 Feb 12, 2009 

Thank you for the explanation, Ken! I decided to go with "tension triangle" and check with the author if he thinks the term fits.

12:40 Feb 12, 2009 

... unless the author has already used this (English) term. The English engineering equivalent of 'Zug' in this context is 'tension' or 'tensile force'. Perhaps the author is thinking about vector diagrams, where the resultant vector of two vectors at right angles forms the hypotenuse of the triangle; the purpose of a gusset in this perspective is to provide a physical 'path' for the resulting stress (tensile force). Another way to see this is that the total force acting 'at an angle' to the joint is constant, and a gusset 'spreads' the force over a longer path (a gradual corner instead of a sharp corner), which reduces the stress level.

Terms such as 'Zugdrieck' are often used in engineering, especially in teaching.

11:56 Feb 12, 2009 

Alternate suggestion: tension triangle?

11:06 Feb 12, 2009 

The article is about shapes of nature (like the triangular shape of a root flare) that could serve as a model for shape-optimized mechanical components.

11:03 Feb 12, 2009 

in conjunction with your other current question is the article dealing with structural damage to a building nearby , preventing root spread / damage?

10:47 Feb 12, 2009 

"Zugdreieck" seems actually like a made up word to me. If you follow the authors logic, a gusset will have the shape of a "Zugdreieck" to fullfill its function (I am sure the shape has something to do with the forces involved, but I don't think it's equal to the "triangle of forces"). So what I need is a word that describes this shape, it doesn't have to be a word that is actually used.

10:22 Feb 12, 2009 

Are you sure this doesn't have any reference to a "triangle of forces"? 'Cos that's what I suspect here...

10:20 Feb 12, 2009 

Would this work:
a so-called "traction triangle" in form of a gusset.?

10:02 Feb 12, 2009 

I think you are right. The author describes his “traction triangle method“ as "a purely graphical method for the reduction of notch stress and the deactivation of predetermined breaking points." The method is outlined as follows: "Starting at the lower 45° angle, a "traction triangle" is placed in the „sharp“ angle. This creates a new, already less sharp, groove above the old one. (...)"

09:54 Feb 12, 2009 

IMO the author is referring, in an abstract sense, to the triangular gussets that are often used to reinforce perpendicular joints. This will probably need some adaptation for English-speaking readers, as I doubt that most of them will immediately recognise gussets at the junction of a tree trunk and its roots (as in the given example).

see e.g.

Build the gusset plates with the ...
512 x 336 - 16k - gif
www.strand7.com

Gusset - Wikipedia, the free encyclopedia
1 Dec 2008 ... A gusset is a device, often triangular, used to reinforce a connection between two components. Gussets are commonly used in engineering, ...
en.wikipedia.org/wiki/Gusset