Ice Anchor Article

[Greg]

Here is a link to an interesting article on ice anchors.

http://www.theascendingpath.com/documents/Ice%20Climbing%20Anchor%20Strength%20-%20MRA%202009%20-%20Marc%20Beverly.pdf

Surprising revelations were that using a re-bored screw is nearly as strong as a virgin placement and that vertically oriented Abalakov anchors are stronger than horizontals.

[*Chris*]

Good paper Greg. Thanks for sharing. The A-Thread configuration results are surprising to me. Data aside, I had to take issue with the writing style... way over the top:

"Much conjecture has been created, leading to dogma, about how good these placements are or are not."

The bollard is fairly passe and somewhat dangerous on ice, because of decapitation and slipping, but is used in the alpine environment.

I guess I expect that a PhD should know to be subtle with use of an online Thesaurus.

[mick]

A-thread, eh - Has anyone actually tried this? Are they saying that an equilateral 60degree triangle is still optimal even with a vertical threading or no?

Tubular webbing also appears stronger but I had thought that 8mm cord was the standard.

[Greg]

Good paper Greg. Thanks for sharing. The A-Thread configuration results are surprising to me. Data aside, I had to take issue with the writing style... way over the top:

"Much conjecture has been created, leading to dogma, about how good these placements are or are not."

The bollard is fairly passe and somewhat dangerous on ice, because of decapitation and slipping, but is used in the alpine environment.

I guess I expect that a PhD should know to be subtle with use of an online Thesaurus.

I hear ya Chris.......these science types are hardly linguists

but they sure are great with numbers

[chossmonkey]

Surprising revelations were that using a re-bored screw is nearly as strong as a virgin placement and that vertically oriented Abalakov anchors are stronger than horizontals.

I wonder how long the rebored holes sat before putting a new screw into it? I could see them loosing strength when they ice weathers and the hole enlarges.

You also have no idea how good or bad the ice is in a rebored hole as there is little or no resistance to gauge when putting the screw in. Unless you can see air pockets or crappy ice by looking down the hole its still a crap shoot.