Foundation condition question

I have sections of my (interior wall) foundation (poured concrete) that (for lack of a better word) are very crumbly. it is rough and crumbly almost like loose dirt. If you can tell what I am talking about from that description is this normal in concrete after 50 years or is it something that needs attention..? I do get some water but not bad in heavy rain I get small puddles all other times its dry.


Thanks again

 

You have some rotten concrete. Not that uncommon for concrete that age. It is due to the fact that the sand was not washed and had dirt in it. It is now breaking down. Yes, it has to be addressed. Not a fun job. We do a bunch of these all year. From what you describe, since it is only in one location, it was just probably that load of concrete. Maybe the bottom of the sand pile had dirt in it. Sorry about that.

 

Looks like your concrete is having troubles due to bad mixture when it was first built, and/or due to lack of vibration when it was pored.

If it is sort of "sandy" or "dusty" even when you continue scrabbing it a lot- than that would be the problem.
Water penetration can sometimes worsen the condition if the concrete was not mixed and vibrated properly when it was poured.

What you can do is:

1- Scrub all loose "sandy" layers untill you reach a stronger layer. If this is not possible (it remains sandy), than just scrub a bit to remove dust and clean the surface.

2- Make it wet.

3- Take cement plus a good quality cement-glue. Make a mixture of 50/50 water to glue ratio. mix it well with cement (no sand) untill you have a thick "paint" mixture. Brush it over your wet wall.

4- Make a second mixture: 1 Cement 1.5 Sand, water plus glue as above. Apply it over the sill humid layer above. Make this layer
(plaster) at least 7 milimeter thick.

This should protect your cement.

Make sure to wet the "new wall" at least 2 times a day for the first 3-4 days.

I would also water proof it with Hidraulic cement, from the inside, 2-3 layers.

Note - that if there are cracks in your concrete than the metal bars
in it were probably damged and got rusty from the water penetration. In such a case you shall have to treat the metal too with some other anti-rust material- before the above job is done.

 

itumen has given good advice for your wall and its cosmetic look.
However if it is in a area that needs support and strength you will have to go to plan B. Good Luck

 

Thanks for the help. From what I can tell it is real bad in the areas where some water comes in through the foundation. By real bad I mean crumbly and dusty with concrete worn away as much as an inch or 2. The whole foundation is not nice and smooth but where there is no water it is much better. Just gritty and dusty. I will try the patch method as I do not think its at the point where it is a structural problem. But I will keep my eye on it.

Thanks for the help