Replacing Retaining Wall Blocks

[crossframe]

We have a segmental retaining wall 8 to 15 ft in height that supports a roadway over a culvert. (Versa-Lok, Keystone, etc.) The wall has been in service 15 to 20 years, and several areas of the concrete blocks have severely deteriorated from what appears to roadsalt-laden runoff and freeze-thaw cycles. (You can easily dig your way through some of the blocks with a hammer.) There are no plans, but there is a geogrid every 3 of 4 courses.

Since the geogrid is doing most of the work retaining the soil, I'm wondering if the blocks can be removed and replaced. This would limit excavation behind the wall, perhaps to the width of a plate compactor, for compaction and to re-attach the grid to the blocks as with new construction.

Has anyone ever seen or done this? I understand that this does not (or may not) addresss the root cause of the deterioration, but it may be an option to consider if it can be done.

Thanks.

 

[concretemasonry]

On an engineered wall, the block are really a substantial "veneer" the holds the geo-grid fabric to reinforce or hold the soil block together.

since the walls are older the block may have been made about the joint tests (DOT's, manufacturers, licensors and some labs). Most of the problems were the cap units that obviously saw all the salt and temperature swings.

If you can be satisfied with the attachment of the grid to the units, that would be a possible solution. I would definitely get the one of the 4 major SRW developers involved because their engineers have substantial domestic and international involvement of higher engineered walls, but the background (they have seen everything) and testing library can be an asset.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[crossframe]

Thanks, Dick. I agree that the SRW engineers have good insight to these types of issues, but they also may be a little more "optimistic" about the performance of the rehabilitated wall. Proper re-attachment of the geogrid is one of my concerns.