Cut Opening in Existing Concrete Shear Wall
Cut Opening in Existing Concrete Shear Wall
(OP)
I have to determine if a double man door opening (6'-0" x 6'-8") can be cut into an existing, 19 story concrete shear wall. The opening would be at the 2nd floor level.
I plan to use a FE analysis to obtain the stresses around the opening.
Can anyone offer any suggestions about doing this. Specifically, what to install to replace the removed concrete. A Steel Frame?
Thanks
I plan to use a FE analysis to obtain the stresses around the opening.
Can anyone offer any suggestions about doing this. Specifically, what to install to replace the removed concrete. A Steel Frame?
Thanks






RE: Cut Opening in Existing Concrete Shear Wall
csd
RE: Cut Opening in Existing Concrete Shear Wall
RE: Cut Opening in Existing Concrete Shear Wall
Check bending, shear, and compression on the wall. You can use finite element, but I would do it by hand as it is quicker.
The bending stresses have two components, one is the stress calculated when you treat the whole thing as a beam, and the other is the bending stress at the top and bottom of the opening due to the shear.
The second stress is easy to calculate. First divide the total shear in proportion to the stiffness of each section of wall. Then apply as two opposing loads at the top and bottom of the section. Taking the two sections on either side as fixed bottom and roller fixed top then you get moments top and bottom from the shear force.
Then if 0.6*Axial DL + tension from the 2 moments results in a compressive force then the two sides will not crack under the wind load.
You also need to check the capacity to arch over the opening under service loads.
csd
RE: Cut Opening in Existing Concrete Shear Wall
Any comments/suggestions?
Thanks for your help thus far.
RE: Cut Opening in Existing Concrete Shear Wall
RE: Cut Opening in Existing Concrete Shear Wall
It may be a little more complicated figuring the reinforcing if you need it for add'l shear capacity, but normally I expect you wouldn't. And yes you would technically have a less rigid wall now because of the new opening.