How much postcrete per swing leg?

FreeBear

stuart45 said:

For the larger play equipment most companies seem to say 350mmx350mmx350mm hole size. Probably over the top, but nowadays they tend to be cautious.

So some 400Kg of concrete - 1.5 bags cement, 4 of sharp sand, and 9 of gravel.

stuart45

Normally you'd use 10 bags of ballast. I'd expect a lot of people to cut it down to 300x300 and 350 deep to use 1 bag of cement and 6 ballast. The OP hasn't said what size holes the instructions recommended. 

GDB2222

stuart45 said:

For the larger play equipment most companies seem to say 350mmx350mmx350mm hole size. Probably over the top, but nowadays they tend to be cautious. 
Postcrete is expensive compared to ordinary concrete, but does reach it's final set after 5 minutes compared to 24 hours, and hardens quicker, so the times not that much different. 
I'd use ordinary concrete and lock the kids up for a week.

Locking up the kids for a week was absolutely standard when we were young, but nowadays the namby-pamby do-gooders tend to make such a fuss! 

casper_gutman

I used anchors like those posted upthread - Ground Anchor kit (4 pcs) (junglegym.co.uk) - which came with a wooden climbing frame/swing set. There wasn't a hope in hell of getting them to screw into the stony, compacted ground here. I built the frame resting on the ground, dug a 450mm deep hole next to each leg, added the anchor (screwed to the leg, so no need to stand there and hold it until the concrete went off) filled the holes with concrete to about 100mm below ground level, then replaced the turf on top.

It's been rock solid for a decade, with increasingly large children and the occasional six foot/15 stone adult using the swings very enthusiastically.

I forget how much concrete I used, but probably not more than the equivalent of ~1.5 to 2 bags of Postcrete per leg. I think a key thing was that I made the holes as narrow as possible at ground level and slightly wider at the base, so the resistance against uplift doesn't just rely on the weight of the concrete but the ground overlying it too.

Bookworm105

Eldi_Dos said:

You can get heavy duty plastic bags with pre mixed concrete in, the bag has a nozzle which you pour recommended amount of water in put plug in noozle and mix all together. Then easy job to take out plug and pour mix into hole.
Not the cheapest way to do it but for a one off diy job its convenient, no tools required or cleaning out buckets afterwards

LOL, do you know what postcrete is? 
It's a lot easier using that than your suggestion.

Eldi_Dos

Bookworm105 said:

Eldi_Dos said:

You can get heavy duty plastic bags with pre mixed concrete in, the bag has a nozzle which you pour recommended amount of water in put plug in noozle and mix all together. Then easy job to take out plug and pour mix into hole.
Not the cheapest way to do it but for a one off diy job its convenient, no tools required or cleaning out buckets afterwards

LOL, do you know what postcrete is? 
It's a lot easier using that than your suggestion.

Density is a element to be considered with concrete,but bow to your superior knowledge in the matter at hand.

markin

postcrete can be very weak, mixing wet is very important to the strength off concrete.

The hole will probably take 1.5 -2 bags.