Bolt pretensioning / Concrete Splitting
Bolt pretensioning / Concrete Splitting
(OP)
Folks,
I was wondering if pretensioning an anchor bolt in a concrete pedestal can cause a splitting failure originating at the bottom of the bolt or am I worrying too much?
I was wondering if pretensioning an anchor bolt in a concrete pedestal can cause a splitting failure originating at the bottom of the bolt or am I worrying too much?






RE: Bolt pretensioning / Concrete Splitting
RE: Bolt pretensioning / Concrete Splitting
Example: Bolt (or embed) is properly sized, but the concrete is green, not capable of giving you full strength. The concrete will fail, but probably at someodd combination of size and shape: It might be a combination of the bolt pulling out of the hole, the cement/epoxy pulling out of the hole, and he concrete separating from itself.
If the concrete isn't strong enough, you'll get a conical shaped pullout. Avoid this by going deep enough with a big enough bolt/embed diameter so the 45 degree cones develope enough surface area to not separate. Bolts too close together will cause overlapping concrete cones = Same result, concrete fails.
Bolts can pull out of the hole if there isn't enough surface area for the epoxy/mechanical fastener to "grip" the walls of the hole. Fix that by going with a deeper hole deeper, getting a bigger diameter bolt, adding more bolts to your fixture.
RE: Bolt pretensioning / Concrete Splitting
RE: Bolt pretensioning / Concrete Splitting
When in doubt, just take the next small step.
RE: Bolt pretensioning / Concrete Splitting