Jump to content

Recommended Posts

Progressing faster than I am with my workshop build. Although in my defence I got distracted having discovered a cobbled driveway underneath the lawn outside the workshop so given it's turned into a quagmire I've decided to strip off the lawn bit and get down to the cobbles.

  • Like 1
Link to post
Share on other sites

You’ve got a building already, that’s cheating 😊

So, my plan for the concrete pour on Wednesday. Would appreciate a heads up from anyone who spots any major issues, while I’ve done plenty of concreting in the past it’s never been on this scale.

I’ve got two helpers and myself. I’ll guide the pump hose and start filling from the back forwards, and they will poke/knock to remove air and start tamping. As we move forward we’ll start to screed it with the tamping board to level it off and smooth it. Once the correct level has been reached all the way across I will use the float to finish it further, if required. I’ve got some areas where excess mix can be deposited, plus will make up a container for the pump to wash down into.

I’m not looking for perfection, just smooth enough to roll a jack or engine crane on so I don’t think I’ll need to re-float later unless I can’t achieve a good enough finish to start with without over-working it. Once I’m happy with the finish and it’s started to harden we'll cover it with polythene sheeting to assist curing, on top of which I’ll lay blankets and finally a large tarp to keep off any rain. Then leave it for several days.

Hoping the weather gods will be kind, but this is Argyll and so rain is always possible. The mix will cope with light showers but a poorly timed one could ruin the finish. So the tarp will be in position ready to be deployed quickly if required.

Link to post
Share on other sites

Yes, if the slab get rained on to any degree, it becomes pock marked and will be forever dusting up. Found this out the hard way. Luckily, it was our cabin/temporary house, and so has Celotex and screed over it. Had it been the workshop floor, would have been a right PITA.

Will you be using a bull float ? That's not as easy as it looks !

Link to post
Share on other sites

Keep the armour 2" (5 cm) away from the sides and about half way in the concrete.

I suggest fitting an "recovery eye" in the back of the shed (strong piece of pipe / tubing to attach a snatch block to if you needs to winch in something "dead"

Keeping the floor "under water" to slow the setting process will make for a very strong floor. The longer it takes the harder they are.

Have fun, take your time and go for perfection.

Bon Courage !

Link to post
Share on other sites

I used to do alot of driveways and footpaths in a previous part of my job and where we were doing it we used to get heavy rain often, some of these might help 

  • Get accelerator or hardener (depends on where you are as to what they call it) it accelerates the curing process.... this will help cure it before the rain, but you have to be certain your up to the job if you do this  
  • Over fill the slab slightly, lol this is the worst issue we had, the amount of panels that would be 5+mm lower than they should have been 
  • When your finished fill a couple of wheel barrows so you have some extra to grab off to fill hollows, spay them with water and throw a tarp over and every 5 min's turn it over with a shovel 
  • when you've finished tamping it down, get a plank and "bounce" the plank on it to bring up a good amount of slurry the more you bring up the better, this was the next issue we used to have, not enough slurry ontop before the bull float so the float hooks the aggregate and have to waste time on the float, if its good I'll go over it 3 times with the float.... start in my finishing direction (side that has the best reach), I then go at 90 degrees (fill in any hollows, hope you looked after the concrete in the wheel barrows lol, if you have brought up enough slurry you can float the extra over these patch pieces so it levels nicely), have a breather or a drink and then float it again in the finish direction with a light hand drawing only 
  • 20min - half an hr come back and edge, if you see something wrong at this stage don't try and fix it you'll make a bigger mess, your better to polish it out in a couple of days time with a grinder 

I like Arjans suggestion for the recovery eye, I'll add that too mine when I get to it lol 

Water is good as Arjan has said problem is when its at the stage where its sort of warm,( the chemical process is happening) the water drops will separate the cement from the aggregate, I had access to Hydro excavators with high pressure pulsing lances so I used to use these to mist on water if we got strong sun and it was drying the top too fast  

I used the hardener, because we were doing patch panels (some of them up too 10 x 8m) they were part of a drive or footpaths so the rain would flow down them and we had appearance conditions we had to meet (like for like) so rain splatter marks like smallfry's or worse washout marks from flowing water were a fail and often ment rework, if its warm and there is no risk of rain you can get a retarder put in that will slow down the curing and give you more time to work the concrete 

Good luck 

  • Thanks 1
Link to post
Share on other sites
1 hour ago, Arjan said:

I suggest fitting an "recovery eye" in the back of the shed (strong piece of pipe / tubing to attach a snatch block to if you needs to winch in something "dead"

Might I suggest a threaded fitting rather than an eye. Dad had the same thought for moving milling machines into his new machine shop so found a scrap top-link from a 3 point linkage and embedded that in the concrete. Ended up not using it as the digger with a long steel pole machine to slide the 3 tonne machine in but now is constantly tripping over it, but being a 3 point linkage is hardened to kingdom come.

Link to post
Share on other sites

Sounds good guys, thanks. Happily gravity is on my side for putting things into this building, unlike the old one which had a horrible slope and step up into it. The idea with this one is that I’ll be able to back a trailer right into it if necessary - making unloading a dead vehicle quite simple in theory. We’ll see how well that theory works when the time comes to move the 110 up :D

Yes it’s a bull float I’ll be using, I’m looking forward to manhandling that thing! But nothing ventured and all that... :i-m_so_happy:

Does bringing up a lot of the slurry not overly separate things within the mix risking making the surface weaker and prone to degradation? Or is this more of a curing issue than an internal structure one?

Link to post
Share on other sites
12 hours ago, Retroanaconda said:

Sounds good guys, thanks. Happily gravity is on my side for putting things into this building, unlike the old one which had a horrible slope and step up into it. The idea with this one is that I’ll be able to back a trailer right into it if necessary - making unloading a dead vehicle quite simple in theory.

It's not so much de-trailering a complete vehicle...I only have the slightest step up to my garage, but let me tell you, getting a 110 rolling chassis up and down it, on my own is sweaty work and not a little dangerous if it goes wrong!  If it's not too late, I urge you to embed a bit of, say M12 studding, into the far end and tie it to the mesh if you can.  Likely it'll end up under a work bench /shelf so if it sticks out an inch or two it won't cause a trip hazard.  Get yourself a lifting eye with and m12 female thread and a come-along, and you can work smarter not harder...

Link to post
Share on other sites

The thing that puts me off putting threaded holes in is eventually they wear out, then you've lost it. 

What about making a more meaty version of this with some bits of rebar spreading out into the slab for strength? you can thread a strop through it to use for winching things in or securing things. Even make a blanking plug for it to leave you with a flat floor.

Are you putting any security in the slab whist your casting? Like a really secure way to lock the doors or a post to stop someone getting a vehicle out?

 

f4e4cd8a12373c448b9c3c8c8d73cb2b.jpg

Link to post
Share on other sites

I don’t have any threaded bar or hoops laying around so I’ll have to do without for now, I can bolt down an eye to winch off fairly easily at a later date if required. Security wise the doors will have bolts that go into the slab at the bottom. No plans for a security post right now but it’s something I could add in front of the building in the future as I’ll be concreting another area in front of the doors in time.

Link to post
Share on other sites

I have two holes in my garage concrete floor, and a piece of angle iron I use a couple of rawl bolts down through.

Works fine, and as you say can be done whenever you want, and have decided the final layout!

If you wanted to do something now, a bent loop of rebar would be plenty.The forces to get a truck rolling are pretty small in all reality, so no need to go mad with it.

Link to post
Share on other sites

All ready to go! :D

5710555D-F42F-4623-864E-1773478A353C.thumb.jpeg.c05c56832f1476be3a29db4194392c72.jpeg

 

Ended up with one layer at the front where it’s shallower, and then a second layer tapers out from about half way down to give two at the deeper end.

I was worried about walking on it but it’s surprisingly sturdy once it’s all tied together. 

  • Like 3
Link to post
Share on other sites

If I were you I would staple/drawing pin or something, the membrane over the shuttering, or it might be pulled below the concrete or the concrete getting behind it, spoiling the nice edges.

Didn't they say, NEXT Wednesday ? 😄

Link to post
Share on other sites

Cheers guys. I’m quite please with the finish straight off the screed/tamp. A few minor ridges but I can smooth them off once it’s started to set if I feel brave enough - or just leave them.

Just in the water bleeding phase now so don’t want to touch it, but I’m sitting guard to stop any rabbits or cats running over it!

  • Like 1
  • Haha 1
Link to post
Share on other sites

Our cats / dogs love to leave prints in soft concrete...... 🙄

We did insert a horeshoe in the concrete for the Horse ABRI

Perhaps you have an old LR rear badge to make a print ?

 

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy