Concrete sub base crumbling after removing frame

[Bymur]

Just had this work done, the wood frame was removed today, and now this problem has occurred! Can someone tell me how this can be fixed, the sub base is crumbling- landscaper told me it was absolutely fine! I’m not happy, the sub base has sand in it which is moist!
How can it be fixed, the huge gap is right next to my fence so they can’t exactly get in there as such!
Help! I’m so disappointed

 

[Justin Passing]

Get a quote from a competent outfit, to put it right;
Sue.

 

[Deluks]

The sub base is supposed to be loose-ish, but it should have been dug into the ground to help contain it.
You could mix up some concrete and haunch it round the edge to contain it.

Or put the wood back, most just leave it in situ after the pour.

 

[Bymur]

It’s very loose, nothing holding it, and I’m sure once the weight of the shed going on it, it’ll eventually give way, the other end was dug into the ground but this side wasn’t- rhe garden is of a stupid level drop, I dont even like how high it is, he’s coming back to tomorrow to move the shed onto the concrete, but how do I even say again that I’m not happy with it! I’ve already explained it today! He says it’s fine and it’ll not drop or break! I’ve not paid yet

 

[noseall]

It’s very loose, nothing holding it, and I’m sure once the weight of the shed going on it, it’ll eventually give way, the other end was dug into the ground but this side wasn’t- rhe garden is of a stupid level drop, I dont even like how high it is, he’s coming back to tomorrow to move the shed onto the concrete, but how do I even say again that I’m not happy with it! I’ve already explained it today! He says it’s fine and it’ll not drop or break! I’ve not paid yet

The whole set up should have been about 50mm or so lower (into the ground) so that the hard core layer was contained. I doubt shed builders around the country would be concerned though. Put some concrete down between the base and the gravel board as a retainer. You are not going to see catastrophic failure here.

 

[JohnD]

It's possible to shutter round loose rocks and pour a runny mix to grout round them.

Not very strong but it would stabilise that mess.

If I had done it myself (unlikely) I would want to break it out and do it again, properly. Easiest, quickest, best solution.

 

[Cheslea2010]

The sub base is fine there's just nothing holding it in preventing lateral movement. Sub base appears to be above ground rather than below it which is the issue. Concrete doesn't look like it has been pokered very well though.

 

[Bymur]

I suggested mixing cement with the loose and use a sleeper to keep it all compact back in, all he did was get 2 sleepers and put them on top of the sub base that’s loose! Then moved the shed! So now no one can get in there and pack it back up/ rectify the issue! I don’t worry as long as the concrete won’t start to crumble and eventually all break down

 

[JohnD]

Make a mental note not to use him for any future building work.

 

[Harry Bloomfield]

Help! I’m so disappointed

How thick is that concrete base?

 

[Bymur]

Very thick! Not what I asked for