Mix for sleeper posts - Help!

[DeanPA]

Having spent the last 4-6 weeks reading just about every thread on sleeper retaining walls, I thought I had every detail covered!

Starting the project this weekend, a sleeper wall 6m wide and 1m high.

Ordered 200 x 100mm new pine sleepers, which I trust will do the job!

I am planning on sinking sleepers in at 1.5m centres as fence posts, then using timberlok screws to attached the horizontals to the vertical posts.

My question is on the mix for the vertical sleeper posts...

I was planning on filling the holes with wet mix (4:1 ballast to cement) but most people seem to suggest using dry mix!

Surely using a wet mix ensures its throughly mixed, therefore stronger?

Is it pretty much universally accepted to use dry mix for sinking sleepers in?

!!

 

[RedHerring2]

I agree with you on this, but I don't use a wet mix, more of a damp mix.
A simple test might be:
take a cricket ball size in your hand, if it just about or nearly holds together without falling apart when you've squeezed it, it's probably OK.
Obviously, if it's holding together as soon as you've picked it up, it's probably too wet, and if it falls apart easily into many pieces, after you've squeezed it, it might be too dry.

The dry-mix proponents suggest that it'll take up moisture from the ground, well, I guess that's correct but it'll take so much longer, IMO.

Incidentally 5:1 mix will suffice.

 

[r896neo]

professionals or people under time pressure use post crete or as postcrete is pretty dear you can mix your own dry concrete as when it is well rammed in it will hold the post relativly level then work can continue. At the end of the day it simply needs a few buckets of water over it much like postcrete. Obviously it depends on what this is, for a fence with hammered in rails etc post need to be set the previous day

 

[Alarm]

Use a dry mix to "bed" the post.
Then put a wet mix on top, it will set fine. Dry mix about 1/3 of the hole.

Put up 1000`s of meters of fence posts this way.

 

[DeanPA]

Thanks for the replies, put my mind at rest

Whilst on the subject, I was planning on sinking the sleepers in (2.4m long sleepers) to a depth of 1.2m...

Is sinking them in to 1/2 length overkill, or would a 1/3 depth suffice? Would save on materials and labour!!

 

[r896neo]

It depends on what height and what ground you are retaining?