How strong is webbing frozen ice?

I went to the Gunks this weekend. When I got to the top of RMC, the webbing for the rap station (two pieces of 3/4 tubular webbing and a piece of 4mm cord) was frozen in a block of snow. Since I couldn't see the back of the anchor, I used a cordelette around the tree and brought up my second.

When he got up and it was time to rap down, I removed the snow from the webbing. It was intact, but still frozen. I had a length of cord with me that we used to back up the webbing.

How strong is webbing if it's covered in ice? I guess that being frozen does not affect the long term strength of the webbing, as I suppose those anchors have been there more than one season.

Yeah, there was some improvement in strength with the frozen slings, but they were testing knots, not sewn slings, so I'm not surprised that the freezing might have: 1. lowered temperature thereby increasing strength, and 2. decreased the slipping of the knot.

If I'm reading the chart correctly, they did not test frozen vs non-frozen sewn dyneema.

You are correct. The slings were tied with water knots.

What about a frozen rope? I think it would not be as stretchy. I'm talking about a dry treated rope that has been used for a few seasons or a non dry treated rope. Does wet freezing rope become weaker?

Brassmonkey wrote: If I remember correctly the frozen slings were the strongest, dont remember exactly why though so I'm not going to talk out of my butt.

The frozen samples were strongest because Dyneema starts to loose strength around 150 degrees F., and it melts around 250 degrees F. As a result, the heat created by the knot slipping is enough to reduce the strength of the material, but if the material is frozen, then the heat created by the slipping of the knot is less of a concern.

I doubt this effect would translate to nylon slings. Nylon melts around 460 degrees F., and waterknots dont really slip in nylon, so there would be less heat created during loading.

I was with jonathan when this happened, and I have a follow up question:

since so much of the tat in the gunks sits in the sun year round, and my understanding has always been that uv is awful for nylon, does that mean the webbing that was fully covered by snow and ice could be stronger than the webbing that wasn't, simply by being exposed to the sun for less time?

This is like, getting to magic bullet level of hypotheses, but I'm curious on everyones thoughts.

Bill Wa wrote:What about a frozen rope? I think it would not be as stretchy. I'm talking about a dry treated rope that has been used for a few seasons or a non dry treated rope. Does wet freezing rope become weaker?

To start out, if your at all concerned about the overall strength of your rope and its ability to withstand load at any point ever, your doing something very very very wrong. Certain knots, different techniques and situations all contribute to the overall strength of your rope, however these factors should always be pretty insignificant because the force required to actually break a rope is magnificent.

With that being said, ice certainly decreases a ropes ability to stretch under load, and in certain situations, this can be an issue. On lead, or in situations where your protection is sensitive or delicate, having your rope stretch under load is an important way to minimize the force on each individual piece of pro. In situations where this is an issue, and the risk of potential injury exceeds what you are comfortable with if a fall were to occur I would do everything I possibly could to ensure that my protection does not fail. I would not climb on an very icy rope if I was relying on non-natural protection. If your someone who leads a lot, or is in situations like this a lot, having a dry-treated rope is important, and replacing it when that coating is gone equally as critical.

20 kN wrote: The frozen samples were strongest because Dyneema starts to loose strength around 150 degrees F., and it melts around 250 degrees F. As a result, the heat created by the knot slipping is enough to reduce the strength of the material, but if the material is frozen, then the heat created by the slipping of the knot is less of a concern. I doubt this effect would translate to nylon slings. Nylon melts around 460 degrees F., and waterknots dont really slip in nylon, so there would be less heat created during loading.

If the knot is inside the ice it may not even get loaded.

Rob Davis wrote:I was with jonathan when this happened, and I have a follow up question: since so much of the tat in the gunks sits in the sun year round, and my understanding has always been that uv is awful for nylon, does that mean the webbing that was fully covered by snow and ice could be stronger than the webbing that wasn't, simply by being exposed to the sun for less time? This is like, getting to magic bullet level of hypotheses, but I'm curious on everyones thoughts.

Basing this just on my opinion, I think that any and all exposure to wind, water, sun, snow etc. would have a degrading effect on material. I'd be alot less inclined to use any of that tat regardless.

Scott McMahon wrote: Basing this just on my opinion, I think that any and all exposure to wind, water, sun, snow etc. would have a degrading effect on material. I'd be alot less inclined to use any of that tat regardless.

I agree with you, but in the gunks it's what we have. I replace old tat when I see it, but the majority of the rapp stations are old worn tat. The climb in question has a path that provides a walk off the back side, but with the ice and snow up there it wasn't ideal

When water freezes, thousands of nanobots descend upon the nylon doing all sorts of nanobotismal things to your gear.

This thread should be combined with the Victory Whip thread.