Redacted
Structural
- Mar 12, 2016
- 160
Hi there,
I have a client that has run into a bit of trouble as they constructed a retaining wall and an open car garage without getting engineering drawings and without inspections and sign off from the local Building Control department.
Needless to say, they have approached me to assist them with reinforcement design and drawings for the Building Control department.
I don’t normally deal with projects like this (reinforcing what is already built), so any assistance would be appreciated.
The client provided some images of the construction process (see attached).
For the retaining wall, from the photos it is evident that the cells are filled and that the rebar either t12 or t16 are spaced at 16” c/c. The footing to me appears to be undersized for a retaining wall of this height (~9’ tall). As a solution I was thinking of designing reinforced pilasters/columns against the existing wall. Spacing the pilasters ~ the height of the wall apart to make the wall span horizontally between them and then have the pilaster footings sized properly to take the moments and associated overturning etc. I’m trying to find some literature on concrete pilasters cast against existing walls for the connection details (if required or if casting against the existing is adequate) etc but I can’t seem to find much. If you have any sources/advice for more information on this type of strengthening it would be greatly appreciated.
Is there a cheaper or better option than this that I should be looking into?
For the beams, I can’t tell the sizing or spacing of the reinforcement in the existing beams from the photos, so I was going to just completely disregard them and design another beam to go underneath the existing. The beams are spanning about 12’ and seem to just be taking their own self weight. I am just wondering how this can work logistically, should I tie into the existing wall or put a pilaster on the end and let the new beam/angle bear onto that. Using an angle would provide the least reduction in head height but I’m a bit weary in using exposed steel as this is a highly corrosive environment; also the span of 12' may be a bit much for an angle.
Any ideas on solutions or topics that I should look into?
I have a client that has run into a bit of trouble as they constructed a retaining wall and an open car garage without getting engineering drawings and without inspections and sign off from the local Building Control department.
Needless to say, they have approached me to assist them with reinforcement design and drawings for the Building Control department.
I don’t normally deal with projects like this (reinforcing what is already built), so any assistance would be appreciated.
The client provided some images of the construction process (see attached).
For the retaining wall, from the photos it is evident that the cells are filled and that the rebar either t12 or t16 are spaced at 16” c/c. The footing to me appears to be undersized for a retaining wall of this height (~9’ tall). As a solution I was thinking of designing reinforced pilasters/columns against the existing wall. Spacing the pilasters ~ the height of the wall apart to make the wall span horizontally between them and then have the pilaster footings sized properly to take the moments and associated overturning etc. I’m trying to find some literature on concrete pilasters cast against existing walls for the connection details (if required or if casting against the existing is adequate) etc but I can’t seem to find much. If you have any sources/advice for more information on this type of strengthening it would be greatly appreciated.
Is there a cheaper or better option than this that I should be looking into?
For the beams, I can’t tell the sizing or spacing of the reinforcement in the existing beams from the photos, so I was going to just completely disregard them and design another beam to go underneath the existing. The beams are spanning about 12’ and seem to just be taking their own self weight. I am just wondering how this can work logistically, should I tie into the existing wall or put a pilaster on the end and let the new beam/angle bear onto that. Using an angle would provide the least reduction in head height but I’m a bit weary in using exposed steel as this is a highly corrosive environment; also the span of 12' may be a bit much for an angle.
Any ideas on solutions or topics that I should look into?
