why would there be a max depth for an epoxy anchor ?

[xtal01]

Sorry, started a new thread as this is a bit of different question.

So, it is too cold to use Dewalt (Power Fasteners) Pure110+ (min temp 41 ... we have snow on the mountain behind me).

I wrote and they recommended AC100+ Gold as it can be used down to 14 deg.

So I was reading the spec sheet just to make sure before ordering a case ...

On a 1/2" threaded rod, maximum embedded depth is 6"

IBC says minimum embedded depth of anchor bolts is 7"

The Pure110+ had a max depth of 10"

Why would a chemical anchor have a max depth? Is this just saying it will not gain any strength going beyond 6" or is there a reason not to go beyond that limit?

Thanks ... Mike

 

[driftLimiter]

They must be tested to get ICC level strengths. Testing protocols include a range of embedment depths for reporting. Additionally your last statement has meaning, there is a limit for sure the controlling limit state might become something other than the epoxy itself.

 

[JStephen]

It might just be limited by the range of the testing that was done to support the design.

 

[dvd]

Curious if the 7" is for cast-in-place anchor embedment.

 

[phamENG]

Could also be a thermal issue. If it's good down to temperatures that low, I'd guessing the reaction puts off more heat so it's able to cure itself. If that is the case (I'm just guessing), and you put too much in the hole you could overheat the surrounding concrete which may cause issues with bond strength?

But yeah, testing limits for the report is also likely.

dvd - you're correct. The 7" is the prescriptive value in the residential code and applies to cast in place anchors for a sill or sole plate. Less is okay if a registered design professional determines the actual loading on the anchors and designs the embedment using accepted engineering practice.

 

[Greenalleycat]

My 2c

1) As per other people, can depend on what testing was done. Some epoxies have specific classifications (e.g. seismic categories C1 and C2 under European guidance) that have to be substantiated with testing. If they haven't tested it, they have to limit use to what has been tested.

2) I don't know if this is correct, but I've got a theory that it relates to a tension lag effect? It makes sense to me that you wouldn't be able to engage the entire length of a very long embedded bolt due to the extension of the bolt above the bottom causing all the load to be taken out higher up.

 

[xtal01]

Thanks guys!

To my surprise, the engineer who wrote me earlier today got back to me after hours tonight (now that is good customer service).

He said that with this product .... " You can put them in deeper, just won’t have any additional rated capacity."

The testing report / specifications says it does meet all requirements for anchor bolts in the IRC.

Looks like I can go 6" or 7" ... it really does not matter.

I know it was a small detail but I like to do things right.

Thanks again .... Mike

 

[FLCraneBuilder]

I would trust the manufacturer's recommendations. They go thru a lot of testing & certification effort on their specific product, while codes are more like std practice

 

[TLHS]

Yeah, I've had this conversation with Hilti when I've needed depth to try to make sure my breakout cone laps into other reinforcement to make sure I've got a load path. Their response was basically "yeah, we've done it, yeah it should be fine, but no we can't really tell you how that performs because we don't really have a reason to specifically test it"

 

[dvd]

Seems like it is anchor steel tensile capacity vs pullout strength of anchor vs breakout strength of shear cone in concrete - no point in having a deeper anchor when the tensile capacity of the steel has been exceeded.