Is Code For Rock Anchoring
Lakia Limthong
At UKC/UKH we are all experienced internet users and as such we understand why some people want to use Ad Block to remove annoying and distracting advertising that proliferates on some web sites. We don't feel that UKC/UKH should be considered as such a site.
We have developed a site that has subtle and appropriate advertising; we don't use pop-ups, we don't force you to read adverts before you can see content, we don't plaster content with adverts, and we don't use third party ad servers dishing up totally inappropriate advertising. We have worked incredibly hard over the years to make sure that we keep a good balance between advertising and editorial content.
As part of a local climbing club I received an email warning of a recent bolt failure due to misuse, so for the sake of public awareness I'm posting the email in entirety below. The failure relates to Harrison's Rocks, but the principles apply to all fixed anchors in southern sandstone crags; Stone Farm, High Rocks, Harrison's Rocks, Bowles Rocks, Eridge Green Rocks and any others with fixed anchors in the area. Information is as follows:
The rocks at Sandstone Crags are very soft and the bolts are put in as a pair tensioned by a wire and should only be front loaded by a vertical rope. [There is a request for] the BMC/HRMG immediately put up signage on the tree that explains the code of practice for the buttress so this does not happen again.
The only way for a leader to gain access to the Buttress to setup ropes is to solo up to the top. I have seen Birchden Wall 5b and Crowborough Corner 5c being used but the easiest way is the Boulder Bridge Route 2b. You can protect yourself by attaching two ropes and a belayer at the top by the tree and another belayer at the bottom to stop your swing if you fall off on the traverse.
The only way you can get off the buttress when you have finished your climb is to climb down your climb or reversing the Boulder Bridge Route 3a as LOWERING OFF IS STRICTLY FORBIDDEN because of the erosion it can cause.
Leaders often put up a SAFETY ROPE to protect the traverse off. This safety rope should not go through any bolts for the same reason of side loading them. The rope is put around the large boulder at the top and then three turns around the tree and back to the bolt on the mainland (front loaded). Climber should attach a small sling to their belay loop with a karabiner called a Cats-tail and then clip it to the safety rope. The safety rope should not be touched or used in doing the reverse Boulder Bridge Route. The reverse traverse should be climbed!
Putting in a bridge is controversial. The rock is soft and erodes quickly; Isolated Buttress is relatively intact because the difficult access puts some people off, as such it will tend to remain in better condition than surrounding rock, for enjoyment by future generations.
I've heard this. As a long-time climber at the crag and as a bridge engineer with a geotechnical hazard specialist as a sibling, I think it will increase erosion of the rock with increased footfall and consequent long term damage. But I accept my voice is only one among many and the decision has been made, so I will grumble on and accept it.
In normal use the anchor bolts are loaded sideways, yes, so the mode of failure is shear through the bolt itself or failure of surrounding material in compression (the standstone 'crust' is pretty stiff so is usually adequate). However, in the scenario above the sling or chord wasn't resting against the rock, so the direction of load has a tension component, hence it blowing and damaging the rock.
The bolt they anchored to wasn't the primary front bolt, nearest the edge of the rock face. They tied into the secondary back-up bolt. I don't know the embedment depths of the bolts but I do know this is not how the system is designed for use. It has failed as a consequence and now the anchor can't be used, the rock is damaged, and the climb is unprotected.
This is starting to sound like Brexit. Have a vote and if it doesn't go the way some want it, have another one, and if that doesn't please everyone have another one, and so on until everyone has died off or forgotten what the issue is, or the Isolated Boulder has been pulled so hard by horizontal ropes and slack lines that it falls over........
If bolts on sandstone are loaded the wrong way then they can twist and loosen. A little movement is ok as the modern bolts are very deep, but some are not as long and are 30+ years old (many are on a list for replacing but still tested and passed checks last year). Although the bolts are tested to be safe (as much as possible on sandstone) they are only tested for direct pull as used for top roping only. Not for any other use, like some of the bolts are seeing on the buttress. The back bolt failed anyway which shows you that someone has not been using it correctly.
Paul, do you know just how weak, internally, the S/E Sandstone is? Almost all the strength is in the iron in the surface; about 4 or 5 mm in, it becomes virtually uncemented sand. I remember once seeing the remains of some overhanging boulder that had fallen off the crag not far from Isolated Buttress (I can't remember exactly where now). It was some quite familiar feature and all that was left on the ground, at the bottom, was a pile of fresh sand.
Because they look trustworthy and generally are? It's not intuitive that using one without tension in a straight line from the other will be enough to break it, I always thought it was more about redundancy like with 2 bolt lower-offs
The rock anchoring industry would sell you a solution to fix a six-lane suspension bridge or a dam to Harrisons Rocks, getting one to take the minimal requirements for roped access or the more stringent ones for rock climbing is easy. Presumably the solution chosen decades ago has proved satisfactory since we dont hear of failures but is open to misuse by less experienced/careful climbers.
Ive been approached about various bolt-testing and design studies for a number of the southern sandstone venues but nothing ever seems to actually be done (though theres a student out there doing something but that will take years probably knowing how they work). Technically its easy to make something better but if the existing bolts keep passing their testing regime I guess theres no reason to do something.
Failure of the traditional 15cm long ring bolts happens rarely but regularly in the Elbe sandstone, usually after the sandstone around the bolt erodes away (many of the bolts have been placed decades ago). More typically the problem is spotted in time, and the bolt replaced after community discussion.
That sounds very convincing, but "Decades ago" invites images of such structures as Stone Henge, and the Severn bridge. But "Decades Ago" can technically also apply to 2008, when the Killers released their 3rd album.
Good to know the bolts are being tested, it's just weird such fixed top roping anchors are only safe in certain loading configurations, and are installed on a BMC owned crag. Do the signs at Harrisons (I didn't read them when I went 'decades ago' ) say Warning! Specific Bolt Clipping Setup is Needed to Ensure Safety?!
Personally I think don't chip, don't wire brush, don't draw chalk all over everything, don't blow torch, don't litter are all common sense. In which case sandstone code of practice can be just: don't use pof and do use a bouldering mat for bouldering
You have to remember why the bolts were placed in the first place. People couldn't be bothered to rig the ropes to the "Get Off My Land" sign properly so deep slots were being cut in the crag. by moving/stretching ropes.
This book delves deep into the crucial aspects of grouted soil and rock anchors, providing a contemporary perspective on the best practices in anchor technology that are directly applicable to the work of consulting engineers, contractors, and students in the field.
The book comprehensively covers aspects of anchor design, construction, testing, durability, and maintenance, as well as the fundamental characteristics of ground and groundwater aggressivity. It adheres to Eurocode 7 and the main current standards and codes of practice, ensuring the information is up-to-date and reliable. The extensive case histories provide real-world examples of successful projects, demonstrating the importance of proper planning, installation, and maintenance.
If it says "On Our Shelves Now" above the "Add to Cart" button, we have it in stock. All other titles will have to be special ordered. The online inventory display is updated every 4 hours. If you wish to check the actual in store stock, please call 319-337-2681 or 1-800-295-BOOK (2665) during store hours.
This is so that whenever anybody clicks on a "Request a free 30 minute call button" throughout the site, they will be taken to the footer.
The client also sends out the following link in her emails:
This link and the p id attribute work perfectly in chrome, but they have stopped working on iOS devices. Does anyone know why this is, and if there is an easy way to resolve this problem?
Thanks
Can someone from squarespace please explain to me why this is a safari problem and not a squarespace problem? Because I decided to deploy a azure static web app for a quick test and anchor 'jump' links work perfectly fine in safari, squarespace / safari bug test (witty-rock-003f16910.3.azurestaticapps.net
This issue needs to be addressed. I decided to move our hosting over to squarespace after the acquisition of google domains and very disappointed that the majority of our website visitors are experiencing a broken anchor tag.
Why is this a safari problem? Anchor tag is working fine on safari in mobile with simple test site hosted in azure. squarespace / safari bug test (witty-rock-003f16910.3.azurestaticapps.net Squarespace is not.
The template used is Brine, I've turned off Ajax loading through the site styles, the sections I'm linking to are sections within index pages so I'm using their unique id as recommended by Squarespace, "www." prefix has been turned off and I've made sure that the URLs don't include the "www.", and the URLs have a / between the page slug and the #.
4a15465005