Concrete mount anchor edge distance with chemical anchors

Video transcript

Hello and welcome to another Tek Talk.

Today I’m going to be going over concrete fixings, in particular with the edge distance on concrete.

We often get asked the question, ‘How close to the edge can we go with a concrete fixing?’

Now I just want to make it clear that it’s very specific to the chemicals you use, and which type of chemical anchors, whether it’s a fast cure and so on.

But, I’ll give you some general guidance in relation to this.

So, as we know with any concrete type fixing there’s always a what they call a ‘cone effect’.

So the ‘cone effect’ is when you get tension on the anchor that cone effect will then break out the concrete.

And that is generally 45 degrees from the base of your anchorage into the concrete.

So when it comes to edge distance, we’ve obviously got to make sure that we’re well within the 45 degrees of the anchorage.

So what that means when we install an anchor near the edge of a concrete slab, that we need to allow at least 1.5 times the depth of your fixing.

So in general terms with our anchors, we have 100mm embedment depth, so we need to allow for at least 150mm away from the concrete edge.

Now in our documentation we always recommend a minimum of 200mm, obviously that is still the criteria as a recommendation, but sometimes you don’t always have that so, to make sure that you have the maximum strength of that anchor, you need to stay at least 1.5 times the anchor depth.

Now if it’s getting to be a little bit tighter than that, we also recommend that you do refer to the chemical manufacturers recommendations for minimum edge distances.

Or refer to our sales team and they can help you with the HILTI Profis software, or the Kattsafe software for calculating what the maximum and minimum edge distances are.

So there we have it, that’s just a little bit of an overview with the anchors in relation to edge distances, and I just want to refer to the chemical anchor manufacturers again, please refer to their documentation, to get accurate strengths on concrete, and again I should highlight the fact that it also has to do with concrete strength.

So 32mpa or 25mpa, it makes a very big difference.

Thanks for watching, and we look forward to seeing you next time.

Thank you.