FENCE POSTS .AAAAGHHH

[andytBEAR]

Hello,
I put a row of pannelled fence in my garden last year, these was 6 x 6 and fixed with posts either side using fence clips. I dug down about 3 ft and concreted every post into ground...now we get to the problem !!
Last time it was windy the post started raising out of the ground with all of concrete attached to them and started to crack the ground around them.
The posts are all wobbly now as the concrete as loosened earth around it.
how can I secure posts securly without digging down as far as Australia ?

 

[JohnD]

was it really 3 ft down or are you exaggerating?

Did you partially fill with soil or was it concrete all the way?

What kind if soil is it?

Was the soil round the posts compacted hard?

 

[andytBEAR]

Yes, it really was 3 ft down by about foot a half sqaure. This was done last summer when ground was quite firm.
at the time digging down, the ground was about 1ft soil and the rest was a hardish clay.
Yes , this was concrete all the way, when I wobble post now all you see is a massive concrete blob trying to come out of ground.
Do you think a spike would help ?

 

[JohnD]

I think spikes are rubbish.

How tall is the fence? What length posts did you buy?

A picture might help.

 

[andytBEAR]

fence panels 6ft by 6ft, post were 8ft of which got set in ground 2ft.
sorry have no pics of this.

 

[JonB]

So really the posts were only in about 20 inches.

 

[andytBEAR]

YES,
IS THIS NOT ENOUGH THEN ?

 

[WabbitPoo]

If the concrete lump itself is coming out of the ground, thge length of the post underground is not relevant. It points to the one (or both) of 2 possibilities:

1) your hole was not the right shape, namely a bit like a bell at the bottom (flared out to increase surface area). I bet yours were getting narrower towards the bottom. Or

2) the ground itself has not withstood the pressure against it caused by the turning motion of the post around its centre of gravity. (less likely if you have hard clay)

If the lump is solid but the post is coming out of the lump then yes, you need more underground (I use 9' posts for 6' panels, though I usually shorten the post a bit), and/or the concrete was crap.

 

[andytBEAR]

Thanks for response.

obviously I need to go and pull this down and start again.

what would be ideal size of hole and what is best concrete as before I used 3 bags of post fix for each hole .[/img]

 

[Thermo]

then youve got far too big a hole. If its a 6 foot apnel you want a two foot hole at least. Go and buy a fencing shovel/trenching spade/newcastle drain spade (all the same thing, long thin shovel with a long handle for digging post holes, about £15 from wickes) You want to dig the hole straight down and bell out slightly at the base so the bottom of the hole is wider than the top. the hole should be about 2-3 inches wider than the post on all sides. It should take a bag of post mix at the most. You need to make sure that you ram it in well around the post then add the water.

if its taken 3 bags then i suspect that youve dug to bid a hole. if youve used a normal spade then it probably is wider at the top than the bottom as wabbit poo says. If you think of that as a ball and socket joint and how easily that moves, thats what you get with the concrete in the ground when the hole is dug like that.

Now since your in sussex get a professional in to do that