Levelling over concrete slab?

[freedomlives]

OK, I think I'll save playing with the plate compactor for some walkways we have to do around here. I've seen some videos of a vibrating wand being used when pouring concrete, but mainly this looks like its used to get the concrete to settle down into complex formwork.

 

[Egon]

Concrete pavers etc. are made in a mold and subjected to heat and high hydraulic pressure.

Using a packer on very dry concrete would be no different than packing gravel.

Vibrating wand's ensure the concrete fill's all of the form with no voids. Too much vibration and the aggregates settles out on the bottom.

The screen & top vibrating for easy finish will leave the top low on fines as well as cement and really help Spauling. It would make for faster easier finishing though.

 

[Egon]

Welded 1/4" grids work well and you want your re-enforcing to be within 1" ( 25mm)of the bottom.

There will be a min. Rebar spacing from the edge as well as aggregate sizes for rebar spacing.

 

[Redlands Okie]

OK, I think I'll save playing with the plate compactor for some walkways we have to do around here. I've seen some videos of a vibrating wand being used when pouring concrete, but mainly this looks like its used to get the concrete to settle down into complex formwork.

Correct

 

[Egon]

Roller packing concrete.

 

[freedomlives]

Wow. That machine would be nice to borrow for a day. We could also get the pothole filled village road sorted out quick! Which, from all that I'm reading on concrete and subbases, is almost certainly a problem of not having a good base anymore, as 10 or 15 years ago gas pipes were put in under the road and probably the filling in of the cuts was inadequate. It has had the potholes professionally filled with asphalt 3 years ago, but by this year they were all back. So the mayor sent around the public work people with concrete to fill in the holes, and that repair has lasted mostly till now. Almost certainly isn't going to make it through the winter! The way social welfare works here, is that those without a job or dependents or anything get 60 euros a month, and then they can work for the village a couple of days a week to get an extra 60 euros. There is only so much weed-whacking to do, so I've noticed he's sending them around more to put concrete in different places!

I guess I've got things figured out for the concrete-- which reinforcement fibers to buy, 10 tons of gravel coming on thursday (0-16mm, so translates to 3/4" crusher run of andesite), polyethylene pond liner ordered since no one otherwise sells thick plastic specifically as a vapor barrier...

 

[freedomlives]

Several years ago I was doing a mud / lime plaster room in our house. One of the things that was suggested in my liming book to avoid cracking was to measure the space in between the sand particles of a given volume of dried sand. The resulting volume would determine the optimum ratio of sand:lime to make good plaster.

I wondered if something similar applied to making concrete. And I found a 2013 research paper confirming that there needs to be at least 1.5 times more cement paste than volume of voids. Which is mostly interesting because what I have to work with is river rock/sand combo. So I can be sure that I'm putting enough cement this way!

http://lib.dr.iastate.edu/cgi/viewcontent.cgi?article=1062&context=ccee_pubs Opens PDF of Study

 

[freedomlives]

Here are the photos covering all of the renovations. There are some of the slab work. I had to first make foundation walls around the whole thing, because the wooden beams that supported it were totally rotten, and then the slab is poured in three parts, all over 2" PS insulation. It ended up being more than a foot higher than grade in front, so there's also a ramp going down. This will, I am sure, in the summer serve a dual purpose as something for the kids to play with their toy cars on.

Vermicomposting toilet system and renovations - Google Photos

 

[Redlands Okie]

Congrats on the projects. Looks like a LOT of work. Ya I bet the kids will have fun with the ramp and the goats After the forum chats its nice to see some of the work you have done.

 

[Egon]

Nice picture coverage.