Opening in Concrete Wall 1

[bsrd]

Need to create an opening in an existing 12" thick concrete wall that is above grade, and supported out of plane to the wall at the top and bottom and is about 18' tall with the opening sill at about 1' above the bottom. The opening will be 12' wide and 10'high and was putting a beam at the top to support gravity loads with columns at the ends and third points. The existing reinforcement is adequate for the shear load that the wall is receiving. I am concerned that cracks may occur at the corners when the cuts are made and migrating out from there. Does anyone have any ideas for reinforcing the corners on one side of the wall with some steel strapping as reinforcing?

 

[Once20036]

When I've had to design new openings in existing concrete walls in the past, I've always called for the corners to be core drilled with a 2" diameter bit, then saw cut between the openings. This serves to eliminate that sharp corner and minimize stress concentrations/cracks at the corners.

If you have the sharp corners, I`m not sure any reinforcing would eliminate the potential for cracking.