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Fixing Bolts with concrete
Posted: Fri Sep 08, 2006 8:52 am
by Frischbier
Sorry for my poor english. I read yor discussion about re-bolting routes with glue-in bolts... and one problem is the cost of the cemical motar. We in Germany use normal concrete (or rapid concrete) to "glue" bolts in. It is a very cheap method. First bolts were placed in the 60´ and still today there are no problems. There are some restrictions: it´s not that easy you need craftmanship, you can´t place bolts in roofs and it need more time.
Posted: Fri Sep 08, 2006 11:51 am
by dhoyne
Doesn't standard concrete have fairly poor mechanical properties? Judging by the roads I drive on, it can't stand up to the freeze/thaw cycles very long.
Posted: Fri Sep 08, 2006 11:56 am
by JB
note to self:
NEVER clip a bolt in Germany...
second note to self:
When were you planning on getting to go to Germany anyway? Loser!
Posted: Fri Sep 08, 2006 12:21 pm
by kirker
Hum.. Sandstone, 4 seasons at the Red, a little hydrolic cement, 8)
You lead I'll Top rope off the tree...
Posted: Fri Sep 08, 2006 1:06 pm
by Toad
That's a great idea. Can somebody run some tests?
Posted: Fri Sep 08, 2006 2:25 pm
by weber
I'll try a few pull tests with hydraulic cement and Fixe glue-in bolts.
Posted: Fri Sep 08, 2006 2:31 pm
by kirker
weber wrote:I'll try a few pull tests with hydraulic cement and Fixe glue-in bolts.
I don't think it would fail the initial tests, but come back every month give it a small amount of use, and I bet within a year assuming its subject to the weather the bolt with hydaulic concrete attached will pull from the sandstone.
Posted: Fri Sep 08, 2006 4:13 pm
by captain static
The use of hydraulic cement instead of glue does have potential merits and is something I have thought about. I would suggest using concrete bonding compound both in the mixing of the cement and to be applied to the bolt hole itself. I have considerable experience in foundation repair and have used various concrete mixtures & bonding compound to repair structural cracks. It is important to thoroughly clean the surface that you are applying the concrete to. I usually make sure the surface is first wet, then brush bonding compound directly on the surface to be repaired before trowelling on the concrete.
For a bolt hole I would suggest cleaning it out with water from a squirt bottle, then applying a mixture of water/bonding compound from a spray bottle before putting the hydraulic cement in the hole. Getting the cement in the bolt hole would be the tricky part.
Posted: Fri Sep 08, 2006 6:45 pm
by ynot
They use the bonding stuff before putting up fake stone on house fronts. Its good stuff. I was bouldering on someones mansion this morning. The crimps were perfect and none of that stuff came loose. Doesnt make sense to use a bonding agent then cement when you could just use epoxy. Can't be that much difference in price and trouble.
Posted: Fri Sep 08, 2006 7:29 pm
by soccerfast007
JB wrote:note to self:
NEVER clip a bolt in Germany...
second note to self:
When were you planning on getting to go to Germany anyway? Loser!
never doubt german efficiency, precision and quality, sie germans are technically quite proficient (i.e. wunderkinder). besides, you may just fall in love with a german, join an oompah band, and trade in your business wear for lederhosen and live in the alps one day...i know i've given the prospect heavy consideration.
i wonder what kind of rock do they have that may be better suited for the concrete system?