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Topic Date User

SRENE anchors may go the way of the dinosaur 13-Mar-2006 At 6:03:42 PM uwhp510

Message

>But this is 100% false.
>
>Your assumption a) is completely wrong and impossible. I agree with your
>physics of the springs but from a basic static force diagram you will see
>that what you are suggesting is impossible. (in physics speak) The horizontal
>components of the tensions vectors in each cord must cancel. (horizontal
>is perpendicular to the fall line).

There are NO horizontal components, because I did the analysis in ONE dimension. Any angle between the pieces will increase the loading, but it will still be shared in the ratio I've implied.

>I am going to make a few blanket statements regarding a two piece anchor
>setup. These apply even if arms are different length. Please if you disagree
>or want explanation just ask.
>
>1. Going back to 'perfect' equalisation. If you managed to perfectly
>equalise the anchor and the cord is completely static then the equalisation
>remains perfect. This is because the angles don't change therefore the
>equalisation can't change.

I will say it again, there are no angles and no such thing as completely static cord.

>2. However in practice you cannot perfectly equalise an anchor and no
>cord is completely static. Any stretch that occurs in the cord will IMPROVE
>equalisation. A really stretchy cord will give better equalisation, likewise
>static cords offer less equalisation.

This is complete rubbish because both arms of the cordalette will stretch, and the one that will stretch the most is the one that is more springy, ie the longer one, which will transfer load to the shorter arm. Try it with rubber bands.

>3. The notion that unequal arms will introduce unequal loading is flawed.
> In fact it makes no difference. If it is equalised to begin with then
>it is equalised for all loads.

Its not a notion, its a proven fact. I'll give you the statics diagram, with a nice step by step explanation, stay tuned.