TRouting op Mat Foundation Reinforcement Through Shear Lug Pockets

[MrFurleyEIT]

I am designing shear lugs for my base plates on my mat foundation. The base plate is sitting on top of the mat foundation and the shear lug and shear lug pocket where they do occur (around vertical bracing areas, primarily) will interfere with the top reinforcement of my mat.

To get a feel of the situation, my base plates are about 15x15 and about 2 inches thick on a 1-1/2 structural non-shrink grout. The shear lug runs the length of the base plate and is 6 inches deep from the bottom of the base plate (i.e. 4-1/2 inches into the mat) and about 1 inch thick. The mat itself is about 18 inches thick. I generally use the minimum 4 1" diameter anchor bolts with embedment of about 15 inches deep. My top reinforcement is about #8 at 10" O.C.

My question is about the top horizontal reinforcement crossing the shear lug pockets. What is the best way to handle the horizontal reinforcement? I am thinking that one of the ways to handle this is to treat the shear lug pocket as an opening on my mat, and stop the horizontal reinforcement just short of the shear lug pocket and bend it downwards. Then provide additional reinforcement around the perimeter of the shear lug pocket and also below the pocket itself. Please provide your opinion whether this is feasible or not. What is the best design approach, or how do I design it?

Is there any other better method to design the reinforcement around the shear lug pocket? Does anyone know of a method so easy that a caveman can do it?

How about running the reinforcement through the shear lug pocket itself and have it embedded in the structural non-shrink grout? Has anyone done this before, and is it a practical solution?

What about base plates with two-way shear lugs? I am guessing the approach above, if acceptable, is similar to the one-way shear lug, right?

Please provide your thoughts and suggestions, and thanks in advance.

 

[civilperson]

Use the coefficient of friction of steel on concrete, (with 0.6 DL), plus the shear strength of the anchor rods, if this is not sufficient then lugs at the base plate become necessary, (very rare). The lugs can be small segments to fit between the reinforcing, say 9" lugs in 12" c-c bar spacing or stop reinforcement before the conflict and use extra area around the hole to match the missing bars.