House stone foundation replacement

[JStructsteel]

Got a house that has a stacked stone foundation. The best I can tell there is movement outward from the wall. I recommended that it be replaced.

Any ideas other than total replacement. Would some piers in front of it and a grade beam do any good (stop lateral movement?)

I did an inspection, no crawl space identified. Its only approx. 12 feet (3ft on a corner, then 8ft perpendicular)

Any other ideas short of supporting the structure and removing?

 

[phamENG]

Any idea what's causing the movement? What's the condition of the mortar? (I've seen dry stack stone garden walls, but never a foundation wall for a house so I'm assuming it was mortared when it was built - I know them as rubble stone masonry.)

 

[JStructsteel]

based on the location, its seems to be water always standing/draining near the footings. See attached.

 

[phamENG]

Oh my...

You may not need complete replacement. First, set up at least temporary drainage fixes. If the structure above is sound and doesn't appear to have shifted, I'd excavate (carefully) to get to the footing/bottom of wall to see what the condition is. Then have them re-point the mortar and reset any lose stones. Then deal with the drainage in a more permanent way.

It looks like you have a mix of old stone foundations and concrete (wall on the right side of the picture).

 

[StrucPatholgst]

Honestly, I'd just recommend excavating that corner and restacking with mortar, and then fix the drainage in the area.

 

[PEinc]

The vertical, white downspout dumps rain water right next to the horizontal, black, corrugated pipe. Then, where does the water go? What is the black pipe for? First fix the drainage and check grading around the house. Get the water away from the house. Then, look at the wall problem.

http://www.PeirceEngineering.com

 

[EdStainless]

Fix drainage first, any foundation fix will be wasted if you don't.
There was house in this area recently that they put beams under as if to move it, but all they did was jack it up a couple of feet and built and entire new foundation with partial basement under it.
If this is really only one corner you could shore the house, excavate, and re-build that section.
Look for rotted sills while you are at it.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[JStructsteel]

The wall is definitely out at the bottom. I was wanting them to replace the return, and then about 8' down the wall. The owner is balking about that, trying to do it cheaper.

He wants to drill some piers extrnal to whats there, and pour them. I was thinking could do that and some grade beams, just let passive pressure do its thing.

Here is another few pics. The farther end actually has some clay bricks too, but they dont seem to have shifted. More at the corner.

 

[NorthCivil]

This kind of work is fun, but terrible for business. No money in it, only massive liability.

Additional to the comments above around drainage, if you could get an idea of the load loadpath, you could do some targeted underpinning/upgrading to the foundation around any areas of high loading?

 

[dik]

I've encountered stone foundation walls that over time have had the lime and sand, 'wash away' due to the lack of hydraulic properties of the lime. Could that have happened?

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[1503-44]

Route the drain away from the house!!!
Then...

https://www.eng-tips.com/viewthread.cfm?qid=486207

 

[PEinc]

First, fix the drainage problem and properly grade the yard area to slope down and away from the house. Then, assuming that there is no basement or crawl space, repoint and parge the currently exposed portion of the loose stone foundation wall, while also inserting some ports or tubes for injecting epoxy between the stones. Inject epoxy between the stones in the wall. Next, excavate a foot or more feet deeper along the damaged length of the wall and repeat pointing, parging, and injecting epoxy. Continue excavating, repointing, and parging in lifts until you get to the bottom of the stone foundation wall. Backfill the foundation wall as required. If there is no basement or crawl, the foundation wall probably does not extend more than 3 or 4 feet below original grade.

http://www.PeirceEngineering.com

 

[1503-44]

There is a lot of thought that one should not inject or repair rubble walls with a bonding material that is as or stronger than the rocks themselves. I'd just use a morter or a sand cement.

 

[dik]

Mortar should not exceed the strength of the units... less of a problem with stone, but a real problem with historic brickwork.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik