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karlbaba
Jul 4, 2005, 5:43 AM
Post #26 of 32
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In reply to: .......The Beal website reference above that showed the actual fall factor to be higher than the theoretical fall factor due to rope drag through the carabiners would indicate that gear placed farther apart would result in lower actual fall factors. Sounds counter-intuitive despite being correct. .....
On the other hand, that website would also seem to imply that if the fall factor is actually higher, that would result in the rope not being fully stretched, and that if a piece ripped, new sections of rope would become available for stretching more fully. It would seem that you can't have it both ways, if friction is keeping the fall factor high by restricting the absorbing potential of the rope within the system, that means absorbing potential remains.
Of course, none of this takes into account the give of the harnesses on both ends of the belay chain, slippage through the device, release of human waste into the climbing pants, or other forces coming into play
Peace
karl
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karlbaba
Jul 4, 2005, 5:52 AM
Post #27 of 32
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Registered: Jul 10, 2002
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In reply to: .......The Beal website reference above that showed the actual fall factor to be higher than the theoretical fall factor due to rope drag through the carabiners would indicate that gear placed farther apart would result in lower actual fall factors. Sounds counter-intuitive despite being correct. .....
On the other hand, that website would also seem to imply that if the fall factor is actually higher, that would result in the rope not being fully stretched, and that if a piece ripped, new sections of rope would become available for stretching more fully. It would seem that you can't have it both ways, if friction is keeping the fall factor high by restricting the absorbing potential of the rope within the system, that means absorbing potential remains.
Of course, none of this takes into account the give of the harnesses on both ends of the belay chain, slippage through the device, release of human waste into the climbing pants, or other forces coming into play
Peace
karl
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adnix
Jul 4, 2005, 7:57 AM
Post #28 of 32
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Registered: May 20, 2003
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In reply to: - The rope stretches its full capasity and length, ergo it cannot stretch anymore, and is essencially static.
The more I've learnt the less I'm interested in rope properties. The difference on forces between a good belayer and a bad belayer can be upto 50%. During the 50s people held factor two falls all the time with hemp ropes and body belay. Sometimes the rope broke but most of the times it didn't.
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adnix
Jul 4, 2005, 8:19 AM
Post #29 of 32
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In reply to: The real safety issue in these scenario is whether hit simething on the way down until your rope stops you, and if you managed to avoid the rope flipping you over (cause maybe it was between your legs.) In a real situation, if you don't hit anything, you're going to be fine with impact forces on your body in any scenario where God is not out to get you, and a good piece is going to hold you. (assuming modern rope) |
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norushnomore
Jul 8, 2005, 1:08 AM
Post #30 of 32
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Registered: Nov 4, 2002
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I think this subject was made more complicated than it needs to be.
As your pieces fail you progressively go from low fall factor to the worst possible fall ff2. That means each successive pro will be taking harder and harder fall factor hit (read: you will hit each successive piece with harder and harder force). As simple as that.
If any piece does indeed hold for some duration of time that simply can subtracted from absorbing qualities of the rope so the end result is about the same: you will hit your next pro with less speed but your rope is more static: same force anyway.
Good news is that you will never exceed max force of ff2 on any given piece no matter how many of them you zip along the way.
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papounet
Jul 8, 2005, 7:53 AM
Post #31 of 32
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Registered: May 28, 2003
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In reply to: As your pieces fail you progressively go from low fall factor to the worst possible fall ff2.
I am afraid this would only be correct if the each pro would blow with nearly zero force.
If a pro do a partial job, the rope will do do a partial job at decelerating the climber. if then the pro blows, the climber resume accelerating. At the next pro, the energy to be dissipated will be less as if the climber did not fall from as high. This being said, computations shared before on rec.climbing have shown that the longer the second fall, the less there is a benefit as the energy grows back quickly.
Ab absurdio, picture the pro blowing just "at the end of rope strech". the climber was close to at rest. the climber will fall twice the distance between the pro that has blown and the next pro onto the full length of rope.
The rope will have relaxed between the two events, but will probably not have recovered all of its energy absorption capabilities.
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renohandjams
Jul 12, 2005, 4:24 PM
Post #32 of 32
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Registered: May 24, 2005
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I had a question. Sorry I'm new to this whole shockload stuff while climbing, but I did get an A in my engineering calculus based physics class so I think I have a good grasp on the theory.
I was wondering, wouldn't it be easier if you were so concerned about shockloading to climb with a yates screamer attached to your harness, or to the first piece of pro that you expect to take a big fall on? Does anyone out there trad climb with screamers? What are the pros and cons?
Thanks
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