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adatesman
Jan 29, 2009, 6:19 PM
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Registered: Jul 13, 2005
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JimTitt
Jan 29, 2009, 7:10 PM
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So now I can´t post this reply to it!
"Nice work. As they say, plagiarism is another form of flattery!
A few points:
Fig 1.5 is of one of my bolts (a belay bolt, hence the relatively large eye) and above this it is stated:-
"In some configurations one spiral can ride up over the other spiral and jam the bolt in its hole; however this probably depends on the direction of pull and can’t be relied on. There is no weld to crack or corrode."
The movement of the two legs in the hole after glue failure is NOT dependent on the direction of pull and CAN be relied on. We have tested hundreds of these bolts and it always occurs, both radial and axial testing. The movement produces a wedging action and raises the pull-out resistance by an enormous amount,this size of bolt getting up to 49kN pulled straight out in granite. We even perform and publish no-glue pull-out tests, the model shown holding 12kN straight out and 20kN radial.
How effective this is is well illustrated by Fig 2 on page 4 which is another of my bolts being tested in very soft ("We purposely chose a softer, weaker piece of sandstone for this test") sandstone in the U.S.A. Rick Weber of Red River Climbing has not been able to pull any of these test bolts out and states they are the strongest bolts he has ever tested. The same results are obtained in tests by the British Mountaineering Council who have not been able to pull out any of our bolts.
The highest value we have yet achieved is 102,9kN for a bolt glued with polyester in granite with a straight out (axial)test.
The section on fatigue (Appendix 6) shows how important correct anchor design is, we have performed repeat axial pulls on our bolts, our test protocol being 1000 x 25kN pulls then raising the force in 5kN steps with 100 pulls each. After 1,362 pulls the test block (granite) failed at 44,6kN. This is with the smallest bolt we produce.
We also perform high frequency fatigue tests with a load of 800N being applied 1500 times minute, we have had no bolt failures and one is still going strong after over 130.000.000 cycles (which reminds me to do something about it)."
Jim Titt, Bolt Products. Germany.
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acorneau
Jan 29, 2009, 7:24 PM
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Page 13, figure 8: "Mildly corroded mild steel bolt on seacliff"
Holy shit, Batman! If that's "mildly" corroded I'd hate to see what they call major corrosion!!!
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grover
Jan 29, 2009, 8:37 PM
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adatesman wrote: Ha! Beat you to it! I added it into the new Bolting and Anchor Systems section of the Lab FAQ a couple hours ago...  Thanks for the heads up though. -aric. ps- you have a typo in the post subject 
Hmmm... I did try a search.. missed it.
Should I erase this thread then.....
Nice and thorough job Jim!
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patto
Jan 29, 2009, 9:32 PM
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This has partly come about because of the recent controversy here concerning bolts some visting European climbers added. They failed to even ensure the bolts were slightly adequate and consequently somebody died.
acorneau wrote: Page 13, figure 8: "Mildly corroded mild steel bolt on seacliff" Holy shit, Batman! If that's "mildly" corroded I'd hate to see what they call major corrosion!!!
I've seen worse. That corrosion looks like mostly surface, I'd clip it.
(This post was edited by patto on Jan 29, 2009, 9:34 PM)
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