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Hilti 150 max to dowel rebar from existing wall/slab to new wall

Hilti 150 max to dowel rebar from existing wall/slab to new wall

Hilti 150 max to dowel rebar from existing wall/slab to new wall

(OP)
I am doweling in rebar from an existing wall to a new wall and from a new wall to the existing slab.  The wall is loaded axially in compression at the top and has a soil and surcharge load from one side.  Therefore, the old to new wall rebar dowels are subjected to shear forces.  The new wall to existing slab is subjected to shear forces and internal tension and compression.

Everything that I read in the 2011 Hilti Guide refers to various failure modes related to anchorages with edge distances, pullouts, etc.  These failure modes do not pertain to my situation.  I furthermore called Hilti's engineering department.  The engineer I spoke with gave me minimal advice, telling me to calculate the concrete bond strength and use ACI Chapter 12 to determine the embedment length.

The only design example I am able to find on the internet is from Gurmak, a Turkish company, and is in metric.  It is good for a check, but I don't believe defendable since factors used in their equations do not have backup basis provided.

Does anyone know how I should go about calculating the embedment length and bond strength per ACI?  Or, any suggestions on a better approach?

RE: Hilti 150 max to dowel rebar from existing wall/slab to new wall

Are these walls side by side or top to bottom??

RE: Hilti 150 max to dowel rebar from existing wall/slab to new wall

(OP)
The walls are side by side with an existing slab below.  

I found the bond strength in Hilti's tech guide and used equilibruim for rebar at T - bond force = 0; where the bond force = (pi)*d(b)*l(d)*bond strength(psi) and T = (pi)*d(b)^2*fy/4.  I got a development length of about 16".  It is at least in the ball park, but seems high.  I'd expect something closer to 10" - 12".

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