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Topic Date User

Slackline - fatigue effects on biners? 16-Jun-2010 At 4:18:44 PM ET

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On 16/06/2010 One Day Hero wrote:
>Its not actually engineers whom you seek, do you think someone can just
>jot out an accurate answer to that question on a piece of paper?
>
>Rather than theorists, ask the guys in the lab........there are thousands
>of people out there logging thousands of hours boinging on exactly the
>same setup you will use. I don't know why they do it, seems rather boring
>to me.....but, the experiment has been done and will yield much more useful
>info than wanky speculation.
>
>So, anybody broken a biner slacklining? Seen one break? Have reliable
>reports of them breaking?
>
>My guess is that it doesn't happen cause you'd have heard about it already...........hey,
>why can't you afford 4 old biners for slackline duties? Are you a single
>mum?

Here's a wanky's theoretician's 2 cents worth...
http://www.physics.usyd.edu.au/~et/slackline.pdf
Feel free to criticise/make corrections...

Though I would like to add engineers are the people with equipment to measure the breaking force of your biners... It's not all done on paper...

However given the time and information I assure you that a wanky theoretician can make a fairly accurate model of the system and provide much more insight of what's happening in your setup... and can tell you if your record breaking highlining attempt is going to likely end in your death or not...

Anyway, you may notice the lack of values in the pdf as couldn't easily find spring constants for nylon webbing, but I plugged in values which I thought were "reasonable" and tension on either biners never exceeded 10 KN...

If someone has more time than me (looking at the Klaw...) feel free to show otherwise, by either showing me what I did wrong, setting up an experiment to measure the force on the slackline (I imagine the equipment/setup would be similar to your break test ones) or any other means...