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soft rock bolt testing:
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miklaw
Nov 1, 2010, 6:35 AM
Views: 7868
Registered: Jan 13, 2004
Posts: 99
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Here in Australia, the Blue Mountains has pretty soft rock, you can hand drill an anchor in 5 minutes. Mechanical bolts have fallen out pretty quickly so we mostly use beefy glue-ins. So I started testing on a chunk of soft rock in a local quarry and tested a range of gear. Our local 2" carrots (tapered machine bolts had a minimum strength of 2500 lbs (4 tests), 2.5" carrots had a minimum of 3100lb (4 tests), 12 mm x 80 mm sleeve dynabolts had a min of 4300lb (2 tests), 80 mm leg 10 mm shaft Ubolts with polyester failed at 7360 in wet rock, and a minimum of 8480 in dry rock (and some stayed in at 10,800 lbs. the one epoxy ubolt of this size is also still in after this load. 10 mm x 100mm eyebolts bent and pulled at a mimimum of 5680 lb This was an epoxy 80 mm Ubolt at 10,800lb which is still in place. The arrows show the point on each leg where the the ubolt entered the rock initially. The upper (right) leg has been pulled out about 10 mm, while the lower leg hasn't moved out of its hole yet.
(This post was edited by miklaw on Nov 1, 2010, 6:39 AM)
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Post edited by miklaw
() on Nov 1, 2010, 6:36 AM
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Post edited by miklaw
() on Nov 1, 2010, 6:39 AM
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