Repairing Crack in Retaining Wall/Foundation

[Dave]

Hello All, I have a 1920s home with a basement garage. On either side of the driveway leading into the garage, there are retaining walls which are about 3-4 feet high. The retaining wall on the left basically continues into the house and becomes the outside foundation wall. This left side retaining wall shifted at some point due to improper drainage in the backyard, resulting in a 1/4 to 1/2 inch crack in the basement garage just inside the garage door. It's obviously the retaining wall that is moving, even though the crack is in the foundation wall inside the garage just inside the door. The crack is diagonal running from outside the door to a low point inside the garage. Anyway, what would be the best method to fix this kind of crack? ANy suggestions would be greatly appreciated. Thanks, David

[Mike]

Dig under retaining wall and jack it up then pour new concrete underneath. May not help much as the crack will still be there but might only be a hairline crack at that point. This is the cheap and easy way.

Other option is to demo the wall, set up some forms, rebar and pour a new retaining wall. This usually isn't feasible since most walls are higher but a 3-4 foot wall is a piece of cake. Once the wall is taken out, you need to drive some rebar/anchors into the remaining walls that stick out about 4+ inches so that the new concrete will attach to the old wall.

[DanG]

I don't have a good mental picture of the problem.

If the retaining wall has moved, you will need to excavate all the soil behind the wall to be able to put it back where it belongs. It may not totally close due to debris in the crack or other deformations due to time.

If you just want to stop it from going further and to waterproof the crack you would still need to excavate the exterior, but only in the area of the crack.

You can use or hire structural repair to the crack using epoxy. The failure can have heavy steel angle and/or plate reinforcing bolted to or through the walls. It may be better to cut the retaining wall away from the foundation, so that a failure in one does not cause a failure in the other. The wall can be waterproofed on the exterior after the repair work is done.

As in so many of these issues, I hope you are just looking for ideas that you might discuss with the appropriate engineer.

(top posted for your convenience) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Keep the whole world singing . . . . DanG (remove the sevens) [e-mail]

[Norminn]

I know almost nothing about masonry, but just offer a couple of thoughts. First, what area of the country do you live and how deep does the ground freeze? The problem may be more of improper draining along with freeze/thaw pushing the wall. Fix that, and perhaps the crack can be mortared? What is "uphill" from your retaining wall? Does the wall have drainage holes? Soil type?