Berger Rigging: Change of “style”

andrewmcleod

Well-known member
Having also just been down the Berger, I think the rigging was generally great and having it all rigged on what will be fairly bombproof threads instead of naff old spits made it feel way way safer (and you don't have to spanner anything up...).

The holes all looked pretty big - probably 12mm (possibly 10mm). It wasn't really 'lightweight' use of dyneema since they used doubled loops and karabiners. Basically you take a lot of pretied loops of dyneema and poke an end through the holes. I'm told that, as long as you don't overdrill the holes, you don't normally need a hook/Abakalov threading tool to poke the loop through even for the V-threads. Then larks-foot it and clip to the carabiner. Shorten the dyneema loop if necessary. Then, for a Y-hang, repeat for another thread and clip into the same carabiner (if you can make the lengths work) and use a bowline on the bight for the rope. Or a normal rope Y hang if not.

I suspect they will have had to replace quite a bit of the rope from overuse, but I would be surprised if they have had to replace any of the dyneema... it's pretty bombproof!
 

andrewmcleod

Well-known member
Also the dyneema will be removed when the cave is derigged. Just means you need ~150??? dyneema loops instead of 150??? hangers and bolts.

I thought it was great :)
 

Fjell

Well-known member
Dyneema is harder than ice and will self-smooth any edges - that is not the case with rock.

Also, more prosaically, is the intent to leave the cord in for general use, or does everyone discard whatever they find and replace with their own (which they then recover)? I am not rigging a big pitch on someone else's 5mm dyneema. This is not the same as a drilled thread you can get a 10mm rope through without a tool.

Unless you leave a cord in it, how would you find it in most situations in a shaft? If you leave a cord in it, I am not going to use it for anything but a deviation. If I have to replace it to use it I am going to recover mine, and prob not get fussed about replacing the old one if I feel it looked dodgy to start with. Very often you would have to cut it to replace it anyway.

Unless you want seriously reduced strength you have to double the cord to place the knot under half the load.

Unlike canyons, you don’t get big rocks bouncing off bolts in the winter in any caves I go down. There is thus no issue with leaving rings or hangers in place.

The FFS Berger team have decided this works for them in a specific situation to avoid placing prob 100 bolts. Up to them. They are also rigging a cave for weeks at a time for hundreds of trips. Time spent on the rigging is of little importance. I cannot see me placing 30 of these for a sport trip.

If I was pushing a deep cave I have no doubt it would be with stainless 8mm studs. Takes about a minute to get one in and they last for decades and are highly reliable in normal limestone. If you overdrill a bit it can be easily hammered flush later. They are not expensive. Self evidently you need less battery power.
 

A_Northerner

Active member
I also went down the Berger last week (I think it was the day after you, IanP). My take-home was that the rigging was done for a balance of longevity and ease-of-use. If it was rigged for ease-of-use on the traverses it would be totally fucked by the end of the first week.

As for the threads, I think it's simply a case of making it future-proof. They don't want to spend time and effort on checking and replacing spits every year. I'm not sure why they're averse to simply P-bolting the place though, maybe that would make the Berger a bit too "sport" for them? I do note that even though there were significant signs of wear on some of the ropes, none of the dyneema looked particularly distressed by the threads, and I was checking most anchors on my way past, due to finding an undone karabiner on the 2nd pitch, giving me paranoia for the rest of the rigging!

The way it's now rigged makes me doubt that they will even let other rigging teams down there in the future? Or at least they'll have to inform teams of the dyneema required to rig the cave. Switching over to dyneema seems to imply they're totally giving up on maintaining the vast majority of spit placements down there, so I don't see why they'd maintain them for other people to use for their own rigging trips.

I spotted the "furry" rope on Hurricane pitch on the way down and back out, we were the front group of the team of 20+ SUSS members heading down. We informed all teams of the wear on the rope, but by the time the third team had reached it on their return journey the rope had been de-sheathed. It was isolated and passed with care, no further SUSS trips made it beyond that particular re-belay until it was replaced. It was "impressive" to see how quickly the rope went from 'Oh, there's a bit of wear on that rub point' to 'Oh f***, the rope is torn'! Must have been maybe 6-8 people passing it in both directions before the rope finally went.

As for the repair job on the rope, what can I say? SUSS will be singing songs and telling tales of Édouard "The Rocket" for decades to come. We were informed that the repair job was in hand when we got back to camp, then when the next SUSS group exited the cave they told us they had been passed at Camp 1 by a single Frenchman running full tilt down the cave, whilst playing a Dance Remix of Captain Jack Sparrow's theme from Pirates of The Caribbean. Several groups emerged after having this encounter, which meant it wasn't simply a hallucination due to exhaustion. Édouard "The Rocket" had set off down the cave on his own, rope in hand, and completed a trip down to replace a re-belay on Hurricane pitch at -1000m in 5hr20m, entrance to entrance, all whilst blasting an EDM remix of the Pirates of the Caribbean theme on a loop the entire time! He would have made sub-5hr if he hadn't had to wait for SUSS members on Aldo's/Garby's pitches.
 

Fjell

Well-known member
Some of the caves at the UIS conference had interesting rigs. A tad casual on abrasion I thought. Whatever.

But the extensive via feratta all over the Vaux cave (includes wire tightrope over terrifying puddle) had comedic value, and the grappling hook left at the end of the last flat out crawl seemed to be in keeping with the main theme.

A842984A-0620-4CD3-B850-5CF9AB16BE51.jpeg
 

Bob Mehew

Well-known member
It was "impressive" to see how quickly the rope went from 'Oh, there's a bit of wear on that rub point' to 'Oh f***, the rope is torn'! Must have been maybe 6-8 people passing it in both directions before the rope finally went.

That is consistent with a similar wear observation in a rope which cored in just 12 uses on Bitch Pitch in JH mine in Derbyshire (see Descent 227 p23 August 2012). Oh and remember to only use an Alpine Butterfly knot to isolate the damaged section (see Descent 274 p16 June 2020).
 

A_Northerner

Active member
Oh and remember to only use an Alpine Butterfly knot to isolate the damaged section (see Descent 274 p16 June 2020).

Isolated on an alpine and thankfully only on a 3m section of pitch, after a traverse and above the final hang, meaning that it could be passed in either direction with relative ease. However high enough off the deck that a fall due to a break in the rope would have resulted in a near certain fatality - if not due to the fall itself, due to being immobilised in the draughtiest, wettest part of the cave.
 

andrewmcleod

Well-known member
There were quite a few resin-bolted caves in the Vercors and in the Savoie region (all Petzl anchors I think). I suspect they didn't want to resin anchor the Berger because of some combination of a) it would be a massive effort, b) it would probably cost a lot (the dyneema is removed at de-rigging time), c) dyneema is more fun :)

I'm not exactly sure who 'they' are, either (the access is controlled by the town hall but I don't know which caving groups have the most influence in the Berger). I know there are groups actively involved in exploration in the Berger who rig it regularly-ish; they also came down (with our permission) during our permit time (SWCC, just before the clean-up camp - the camp rigged the cave for us in the first two days). They were pushing something big and exciting above the Grande Cascade...
 

ChrisB

Active member
A big difference of Abalakovs compared to P anchors is that (discounting rock fractures which are the same for both), P bolts are designed to fail slowly and visibly, ie, they go loose long before they pull out. Dyneema abraded at the hole junction would fail suddenly. On the other hand, the dyneema can be inspected and replaced, while the resin is not inspectable. Provided the dyneema has been inspected/replaced after a certain amount of use, which I imagine can be organised for somewhere like the Berger, it should be fine, but I wouldn't want to use Abalakovs with the usage pattern of most UK caves.

As a further thought, after drilling the holes I'd thread an abrasive cord, and work it back and to to take off any sharp corners. Not sure how I'd make the abrasive cord, maybe something like carborundum beads or washers on a dyneema core?
 

cap n chris

Well-known member
Abalakovs exist in a fair number of UK caves, and potentially ought to exist in many more (suitable) ones, and doubtless with time will. Softening the edges is important, not particularly difficult and easily resolved in relatively short order. I am a fan.
 

andrewmcleod

Well-known member
A big difference of Abalakovs compared to P anchors is that (discounting rock fractures which are the same for both), P bolts are designed to fail slowly and visibly, ie, they go loose long before they pull out.
P bolts do often fail slowly and gradually when they are pulled out, but they are designed to stay in. There's no requirement for any anchor to fail gradually AFAIK.

Incidentally, I would guess there are probably more examples of P bolts still nicely placed in rock that has fallen off than there are of P bolts that have actually failed completely? (rather than becoming a bit loose/wobbly, which I know is a 'failed' anchor)
 

ChrisB

Active member
P bolts do often fail slowly and gradually when they are pulled out, but they are designed to stay in. There's no requirement for any anchor to fail gradually AFAIK.

I had some discussions with Bob Mehew in 2007 when alternatives to the DMM Eco anchor were being considered and we established that gradual failure was a design intention in the Eco anchor. I've only just come back to caving so I don't know about the current anchors. I'm not aware of a requirement for gradual failure in any codes or standards, but it's certainly desirable, and that was stated in the draft report on Eco anchor alternatives.
 

Ian P

Administrator
Staff member
I had some discussions with Bob Mehew in 2007 when alternatives to the DMM Eco anchor were being considered and we established that gradual failure was a design intention in the Eco anchor. I've only just come back to caving so I don't know about the current anchors. I'm not aware of a requirement for gradual failure in any codes or standards, but it's certainly desirable, and that was stated in the draft report on Eco anchor alternatives.

Details of the anchor currently used by the CNCC (Sincere thanks to Simon Wilson for his efforts and technical expertise)
A big advantage of this anchor is that they are designed to be less prone to rock damage when extracting them. This is not the case with some of the other types.

 

ChrisB

Active member
Details of the anchor currently used by the CNCC (Sincere thanks to Simon Wilson for his efforts and technical expertise)
IanP, thanks for that. Having read all the pages on the link, my thanks to Simon Wilson too - as a fellow engineer who has spent some time thinking about the subject I'm most impressed by the design and testing of the anchors and the clarity of the explanations.
 

ian.p

Active member
having gone down the Berger at the UIS conference with this set up i thought it was excellent.
1. Same rules apply as using a bolt you shouldn’t be on one anchor there’s always a chance the rock will fail. Slightly less of a chance the rock will fail when it hasn’t had a shallow expansion bolt like a spit put in it.

2. Holes don’t rust or corrode.

3. I think if you used wire in the holes they would potentially wear into the rock very rapidly.

4. Dynema much lighter than bolts hanger plates and crabs.

5. If somone clips a crab or maillon in and leaves it behind to corrode itself shut it’s much easier to remove it by cutting away a dynema cord than trying to hacksaw a mailon out of a resin anchor.

6. The amount of traffic going down the Berger when we were out there was enormous if there was ever a way to validate a system rigging one of the most popular alpine trips in the world and then holding a massive international caving conference next door is a pretty good one. I’d say it’s pretty apparent that it works.
 

langcliffe

Well-known member
One interesting aspect of the rigging topo is the differentiation between 'AF' (drilled anchor) where the the doubled Dyneema can be easily threaded, and 'AB', where an abalakov hook is required.

 

Leclused

Active member
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