Concrete Mix ratios

[boban]

Boban,
I have no problems about where he can hire a vibrator but have you got any suggestions as to where he might be able to borrow one.

Every concretor I know has one, so I guess thats the answer. If he dont know one, then hire is the only option. That said a stick will also do the same job, its just a hell of a lot harder. You know when its been vibrated sufficiently when the top of the concrete gets a bit of slurry (water and fines).

BTW all the walls we have done have had reo from the footings into the blocks and across the blocks. Has this been done? If not I hope the walls not too high.

[DavidG]

See
http://www.reade.com/Particle_Briefings/spec_gra2.html

Concrete, Gravel 2.4 tonne/cubic metre = 3.6 tonne

[journeyman Mick]

Jeremy,
if you really want to do this I don't think you should let the concrete specs put you off (but you might want to think twice about the hard work ) It would be almost impossible to not make the resultant mix stronger than specified if mixing by hand. the last bit of core filling I did was the retaining wall of my shed, only 1M high (5 courses) so no running up and down a ladder with buckets of sloppy concrete. There were about 220 blocks to fill and it took us about an hour and a half and a carton of beer. There was my next door neighbour and his son (both blocklayers) my cousin and myself (a landscaper and a carpenter) so there was four of us, all fairly used to working with concrete, plus two mixers and a swag of buckets. Working by yourself, with one mixer and not too much climbing up and down ladders you might knock it over in a long day. Make the mix reasonably sloppy, but with enough cement that it doesn't seperate and use 1/2" gravel. Use a length of reo rod to get the air pockets out by rodding each core thoroughly. Years ago before pumps were common and cheap we did hundreds of houses like this. Never seen a vibrator used in core filling though, I'd be a bit worried that the vibrations and pressure on a high wall might blow out the mortar joints at the bottom.

Mick

[jlamplough]

Thanks all,

I've decided to get a few friends around with wheelbarrows and get the mix delivered. The charge for waiting while we unload is much less than a pump. Since it is only 150 blocks and I can access the top of the wall without ramps etc, I don't think it'll take too long.

Thanks for the advice,
Jeremy.

[journeyman Mick]

.............I've decided to get a few friends around with wheelbarrows and get the mix delivered...................

Your friends know about this do they? Well it's one way of finding out who your friends really are.

Mick

[dallas]

ahhh.. the power of the forum search button!

i'm just abuot to do this very task myself (and what would you know, 150 odd blocks also!)... silly question, so here goes..

i'm also assuming that you need to build the wall up to it's finished height, let said wall set, then core fill the wall??

D

[jlamplough]

ahhh.. the power of the forum search button!

i'm just abuot to do this very task myself (and what would you know, 150 odd blocks also!)... silly question, so here goes..

i'm also assuming that you need to build the wall up to it's finished height, let said wall set, then core fill the wall??

D

Yes. Put all the required steel in the wall and then when any engineering inspections have occured, fill it with concrete. Getting the truck in with wheelbarrows worked fine.

jeremy.