To bolt or not to bolt?

[cap n chris]

A video posted on Google Video showing body belaying taken to its logical extent! I'm sure DP will post a link to it for you sometime.

 

[NigR]

Probably not.

Honest of you to admit this but hardly surprising. A little bit frightening too.

So, you are a troll, then?

Thanks to menacer for saving me a google!

Let's look at the definition then:
"....a troll is a person who enters an established community such as an online discussion forum and intentionally tries to cause disruption, often in the form of posting messages that are inflammatory, insulting, incorrect, inaccurate, absurd, or off-topic, with the intent of provoking a reaction from others."

OK, let's see: I am not intentionally trying to cause disruption - I am not posting messages which are deliberately inflammatory or insulting (in fact I'm trying really hard to be very polite) - in all my posts I have tried to be as accurate and correct as I can possibly be - all my posts have been very much on-topic and none have been absurd (at least in my opinion) - and I have never set out to provoke any kind of reaction from anyone (although I am still waiting for answers to some of my questions). So, no I am not a troll (phew... that's a relief).

 

[whitelackington]

I wonder why,
in one of The United Kingdom's most important caves,  O.F.D.
"they"
have decided NOT to go down the "p" bolt route? :-\

 

[Peter Burgess]

In this thread there are a number of posts which have been very well put together. The words and phrases themselves, read in a clinical way, are factual, not particularly offensive, and are not that contentious. So why is it when I read them, I feel they are being posted by an aggressive person, a bit too fond of his own opinions and certainly not someone whose company I would enjoy? Those posts do nothing to persuade me to the way of thinking offered. I may, of course, be barking up the wrong tree, and said person is a really nice guy. Judgements are best not made solely from written words.

Why can't this thread be put back on topic? As far as the original question is concerned, I obviously have no valid view as I am not someone who has ever placed a bolt in any cave at any time.

 

[cap n chris]

Peter, I think the topic has reached a conclusion: IMO it is this:

Bolts have their uses; there are a variety of bolt types - with pros and cons depending on purpose, placement, ability, understanding etc..

Generally the placing of bolts in frequently visited systems is something undertaken by RCCs and people should avoid proliferating their own bolts for a variety of reasons. There are instances where placing bolts is understandable and reasonable; specifically, RCCs are often not in the loop where off-the-beaten-path bolt placement is concerned, be it for digging purposes, exploration or in some non-cave environments.

No doubt there will always be examples where someone will say "Bolt it" whereas others would say "That's not necessary; there are other ways to solve your problem" and I imagine this topic will remain contentious forever. Healthy debate and the occasional argument are part of family life and I see no reason why they shouldn't play an ultimately constructive part of UK caving life.

 

[darkplaces]

A video posted on Google Video showing body belaying taken to its logical extent! I'm sure DP will post a link to it for you sometime.

LOL Yes, and Graham, us mine explorers carry backup fat blokes instead of putting bolts in. The details of which can be found here.
http://ukcaving.com/board/index.php/topic,3513.0.html

 

[Hatstand]

A video posted on Google Video showing body belaying taken to its logical extent! I'm sure DP will post a link to it for you sometime.

LOL Yes, and Graham, us mine explorers carry backup fat blokes instead of putting bolts in. The details of which can be found here.
http://ukcaving.com/board/index.php/topic,3513.0.html

quality!!! 

 

[AndyF]

I'm phoning the HSE, i'm sure thats not in the regs.......  :tease:

 

[Bob Mehew]

Sorry NigR to have kept you waiting, but I have been else where and not had a chance to check the forum until today.

The simple answer is effectively zero.  And before any one else says it, I will happily admit it is because I am a stupid old fart.  Old because it was decades ago when I place a few anchors (using star drills so you really did tap the rock), so my experience is not relevant.  Stupid because I have been prepared to help those who do have a reasonable understanding of current anchors (and placed a fair number of them) to extend their work by doing the boring stuff like doing research, writing things up and push that information out so others are aware of it and help test anchors (well in a month or so's time).

As you seem to have a fair amount of experience, I am sure your comments on the discussion document on anchors (see http://british-caving.org.uk/?page=129 ), especially on the parts which deal with how to bolt, will help to keep the BCA anchor system as one of the best in the world.  And that is my primary interest as i hope it is yours.

Bob

PS For any one who is thinking of asking about my experience with ropes; again I have not used them for real in decades, I just break them.

 

[Bob Mehew]

For Cap 'n Chris re testing on bolts / anchors. 

See ETAG 001 at http://www.eota.be/html/endorsed.htm .  A dense read possibly better done by reading / scanning Annex C, then Annex A & B and then Part 1 before going to Part 2 which covers torque controlled expansion anchors, (Part 5 covers bonded anchors).  The only problem is that it is all about anchors in concrete.  My search for info on anchors in rock is still not getting anywhere.  (But I have been told that they only use concrete because it can be easily reproduced with the same characteristics.)

Another major problem is that it would appear that all of this anchor in concrete work is done on static (or semi static) loads and not for dynamic.  The mountaineering standard (BS EN 959:1997) uses concrete purely because it is reproducible and apparently has no data with actual rock to underpin it (to paraphrase a guy from the British Standards committee).  Whilst most caving usages would be semi static, I think having a handle on dynamic response would be prudent and definitely reassuring.

 

[graham]

For Cap 'n Chris re testing on bolts / anchors. 

See ETAG 001 at http://www.eota.be/html/endorsed.htm .  A dense read possibly better done by reading / scanning Annex C, then Annex A & B and then Part 1 before going to Part 2 which covers torque controlled expansion anchors, (Part 5 covers bonded anchors).  The only problem is that it is all about anchors in concrete.  My search for info on anchors in rock is still not getting anywhere.  (But I have been told that they only use concrete because it can be easily reproduced with the same characteristics.)

Another major problem is that it would appear that all of this anchor in concrete work is done on static (or semi static) loads and not for dynamic.  The mountaineering standard (BS EN 959:1997) uses concrete purely because it is reproducible and apparently has no data with actual rock to underpin it (to paraphrase a guy from the British Standards committee).  Whilst most caving usages would be semi static, I think having a handle on dynamic response would be prudent and definitely reassuring.

Maybe we should just cast girt blocks of concrete at pitch heads to put the bolts in?

 

[cap n chris]

We already have; Star Mine being a classic examplette.

 

[Bob Mehew]

We already have; Star Mine being a classic examplette.

but did you sieve the aggregate to show it was of the correct size distribution, add the correct ratio of water to cement, take a couple of test samples to demonstrate the concrete reached the desires compressibility strength level and so on?

 

[graham]

 

[cap n chris]

We already have; Star Mine being a classic examplette.

but did you sieve the aggregate to show it was of the correct size distribution, add the correct ratio of water to cement, take a couple of test samples to demonstrate the concrete reached the desires compressibility strength level and so on?

In between stuffing some baked beans, plaiting grass blades, counting stars and watching trees grow, we did these other important tasks too.  Hmm, no really; we didn't do anything of the sort, therefore we have no examplettes whatsoever. Scrub previous post. Ta. 

 

[Bob Mehew]

In between stuffing some baked beans, plaiting grass blades, counting stars and watching trees grow, we did these other important tasks too.  Hmm, no really; we didn't do anything of the sort, therefore we have no examplettes whatsoever. Scrub previous post. Ta. 

I will own up and take no credit for making that observation because it has already been asked for real!  I feel very frustrated that we can't find some clever way around it which does not take us into the realms of stupidity (like setting up a 6 monthly testing program as in BS EN 795:1997 or taking the massive anchor test rig down and testing them to BS EN 959:1997).  Unless ... did you use concrete sewer rings purchased from some where or other?  That might get us a handle on the quality of the concrete, even though it would require some extra work as the depth of concrete in which the anchors are placed is probably not sufficient to meet the codes.

 

[graham]

Bob

I am unconvinced that we can ever devise a testing procedure that is practical in caving situations and compatible with what they do in industry. This is for the reasons that you note, about reproducability.

 

[cap n chris]

I bolted Star Mine lid with eco hangers which were subsequently pointed out as being outside of their installation protocol; they have subsequently been tested by CSCC's finest bolting coordinator who subjected them to a massive 10kN which they passed with flying colours. Tea and medals all round.

 

[Bob Mehew]

I am unconvinced that we can ever devise a testing procedure that is practical in caving situations and compatible with what they do in industry. This is for the reasons that you note, about reproducability.

I accept not every case, but.  Take for example concrete sewer rings which almost certainly are made to a standard.  Perhaps we can get one ring, work up an installation with either resin based anchors (or perhaps stainless steel anchors which are bolted through the wall) and test them to show they meet the Mountaineering Standard for anchors.  That would then only require the digging team to get hold of the relevant specified sewer ring to provide a new entrance with acceptable anchors (assuming an acceptable means of securing the ring has been provided).  Alternatively. for where some one is casting a large entrance using ready mix concrete; a few test cubes could easily be taken and subjected to compression testing to show the concrete is up to strength.  OK in both examples this entails more work than perhaps envisaged by the diggers (as well as for the team who do the original testing and set up the standard), but it would give a more permanent solution.

But underground, yes I think one is back to only using sound rock (though I may fantasise over getting a ready mix concrete truck down GB!).  However I would accept that this would be running before we have even got the BCA Anchor scheme up to date.

Sorry Chris, I had forgotten it was Star Mine which had come to my attention.

 

[graham]

You make the point yourself - even if you can ensure that the concrete used is to industry standard, there is then the little matter of ensuring that its installation is to an accepted standard.

What it really comes down to is: "what are we trying to achieve?" "How does this relate to current industry standards?" and "To whom might we be answerable?"

And note how I completely ignored the conservation implications of your fantasies about G.B.