Gabion wall -2 walls actually 360’ length the other 1250’, homes are are about 5-6’ off the top wall

[Mdntramble17]

Are there any basic tricks or tips or monitor movement of a mse reinforced sloped gabion wall ? What constitutes a failure? Thanks

 

[LOTE]

Generally there is a tolerance for the wall batter, say 2-degrees from the design batter (confirm with the wall design drawings). The batter should be checked. You can monitor the face for rotation and sliding.

From your picture, I would be concerned about the foundation being undermined and saturated, causing the wall to settle and eventually lead to bearing failure. The wall should also be evaluated for backfill loss behind the gabions, and intrusion of fines into the reinforced fill. At the time of this picture, it appears the drainage system has failed, not the wall.

 

[Mdntramble17]

Sorry I didn’t upload the photos properly, but I agree thanks for your advice. Yes it was very odd, no rock at them foundation nor face of baskets. Naturally erosion has washed much of the soils already i can
Stick my arm all the way at some point through the face of baskets. And then deep horizontal and vertical cracks up 14”, walls 3-4 months old.

 

[geotechguy1]

Often failure of these walls is more of a serviceability thing where people start noticing it's deflecting outwards or deflecting / settling unevenly. Outward deflection of 1% of the height wouldn't be unexpected although if you were monitoring it you'd expect that to happen not long after construction and then stop except seasonal movements.

It looks like there is water flowing over the wall so you may have more of an erosion protection / water flow issue. Agree with LOTE that the bottom of the wall is going to get undermined

 

[geotechguy1]

I guess you also need to think about 'Risk = hazard x probability x consequences'. If the wall does fail catastrophically the houses are in the runout zone.

Usually gabion walls are built because they are the cheapest option and by very questionable contractors / designers so it wouldn't be surprising to find that the whole thing is under designed. 'Cut the toe out of this slope and put some gabions in to make a flat spot for houses without proper investigation / design / construction monitoring' is a very common repetitive script for a failed wall and decades of litigation. Happens all over Canada and the US.