|
|
Forums:
Climbing Disciplines:
Trad Climbing:
Re: [fresh] Most Worthless Piece of Gear:
Edit Log
|
|
jt512
Oct 18, 2010, 4:40 PM
Views: 4984
Registered: Apr 12, 2001
Posts: 21904
|
fresh wrote: jt512 wrote: ptlong2 wrote: jt512 wrote: This implies, perhaps surprisingly, that the maximum impact force (on the climber) in such a toprope "fall" will be twice the climber's weight, and perhaps more surprisingly, it will be so for a rope of any elasticity. Any linear elasticity. If the rope deviates from Hooke's Law over the range in question the force may not be twice the climber's weight. Yes. I stated in an earlier post, the model assumes that the rope behaves according to Hooke's Law. Jay I swear, the stars have got to go. do you know how accurate Hooke's Law is in predicting the rope's behavior?
As I understand it (which isn't that well), the main difference between a Hooke's Law spring and an actual dynamic rope is that a dynamic rope acts as a dampened spring, resulting in lower impact forces than predicted by Hooke's Law. The standard model also ignores friction between the rope and the anchors or climbing surfaces, assumes the belay is static, and that the falling body is rigid. Were it not for friction, we could probably say that Hooke's Law overstates the impact force on the climber, the belayer, and the anchor. Modeling the effects of friction throughout the system is more complex.
Jay
(This post was edited by jt512 on Oct 18, 2010, 7:39 PM)
|
|
|
Edit Log:
|
|
Post edited by jt512
() on Oct 18, 2010, 7:39 PM
|
|
|
|
|
|
