anchor points - what size weight etc.

[d]

I am looking at installing some anchor points that my scouts troop could use.

We intend using them to tie off heavy rope that will form part of a rope type bridge that the scouts will build.

the idea is that you have two 'A' frames one at each end, the rope then goes over each A frame and ties off to an anchor point.

What i need to gauge is what size would the anchor point need to be - there would only be person on the rope at a time but i would want to estimate say

3 persons so that its well anchored.

The anchor points will be buried in a field so im thinking of say a metre cubed of concrete and then some rebar loops buried in them to tie off the ropes and have them about 75mm below ground level to to avoide the lawn mower catching them.

is a metre cubed way too much, would prefer to use less concrete and dig less soil out :-))

looking for some advice please - thanks d

[R]

Before you go spending vast amounts of money, time and effort on bloody great lumps of concrete, spend an entire weekend digging and getting all hot and sweaty, then have to wait a few weeks before you can use the blocks for anchorage have a look at.....

'll do *exactly* what you need in a 10th of the time and are instantly usable.

(Recommended by someone that has installed over 2000 for a Dry Ski Slope matting retaining system)

[Bob Minchin]

Sounds way OTT to me.

Take three hefty lads 100kg each, allow factor of two for dynamic loads makes 600kg. Under all circumstances I can think of there will be a component of this load going into the ground so less than 600kg into the anchor point.

1m cube of concrete is over two tonnes so nearer to 0.5 m cube would be about right.

When I was in the Scouts we used to use three wooden stakes driven in line into the ground about 30 degrees off vertical with a stout log lying on the ground behind all three and the ropes tied off to the log. I seem to recall an illustration in Scouting for Boys of the arrangement although I no longer have my copy.

Bob

[GeorgeD]

Screw anchors are another alternative:

[Steve Walker]

also a moral value in the lads achieving this through patient, thorough work, rather than buying a solution....?

[John]

In article , Bob Minchin writes

When I was a Scout, we used a 3-2-1 picket with lashing between the top of the three and the bottom of the two and the top of the two and the bottom of the 1 to give added advantage - can't remember them every pulling out.

[d]

Steve,

yes spot on there, the concreting is part of the job really, cheap and have the scouts do some of the graft, learn how to mix concrete etc. we just liked the idea of fixed anchors a bit of time saving when we are doing lots of other pioneering.

yes do like the idea of the ground anchors too but cost is likely to be a show stopper, might have a look at the eath anchors so will look into that as well - thanks for all the useful comments guys.

[Matty F]

I needed a similar anchor point to hold up a retaining wall. I buried a railway sleeper on its side and at right angles to the pull direction and attached a chain to the middle.