Browse Forums Building A New House 1 Apr 09, 2008 7:51 pm Internal and External Building and Colour Consultant Online - Worldwide http://www.denovoconcepts.com Re: How to Evaluate Cracks in Poured Concrete Slabs & Floors 2Apr 09, 2008 8:03 pm That's an excellent website you found...and the take home message is that most slabs will show signs of shrinkage cracking and aren't of great concern.
In commercial construction they'll control the cracking by adding joints (like a footpath) and use the top layer of reo to control the extent of cracking, whereas in domestic they'll just let the cracks occur wherever with the top layer of reo controlling the extent of cracking. Stop me...I'm getting into engineering goobledegook! mmm....donuts Homer Simpson 1956- Links: Site Costs Ready Reckoner | H1 Addiction Medical Advice | Château TDL: The Backyard Re: How to Evaluate Cracks in Poured Concrete Slabs & Floors 3Apr 09, 2008 8:06 pm Thanks for that - excellent resource Mish. I'm due to have my slab pour on Friday so I know I'll be going over it with a fine tooth comb Dana -------------------------- Building with DFH - carpet installed! Re: How to Evaluate Cracks in Poured Concrete Slabs & Floors 4Apr 09, 2008 8:17 pm I have found most guys who work with concrete know their stuff!
Cracks are bound to happen; it’s just the amount of cracks and depth you need to worry about. But this is rare! I have posted this to help relieve some doubts about cracking! Glade it helps! Internal and External Building and Colour Consultant Online - Worldwide http://www.denovoconcepts.com Re: How to Evaluate Cracks in Poured Concrete Slabs & Floors 5Apr 09, 2008 8:20 pm So what do you do if you want a polished concrete floor, as we do?.....if we can afford it
Do you just put up with a cracked floor? 'chelle We have a hand-over date...15/10...but I won't hold my breath! http://people-in-glass-houses.blogspot.com/ Re: How to Evaluate Cracks in Poured Concrete Slabs & Floors 6Apr 09, 2008 8:24 pm Ahhh, this is a different type of pouring!
Much more care goes into a floor that is left bare, so to speak. That’s why you pay more money! And no……you don’t put up with cracks in polished floors! Internal and External Building and Colour Consultant Online - Worldwide http://www.denovoconcepts.com Re: How to Evaluate Cracks in Poured Concrete Slabs & Floors 7Apr 09, 2008 8:29 pm Well that's good to know - not that we pay more....already knew that - but that they do take more care. Our designer has already warned us that it is almost impossible to guarantee a crack free floor though. Hopefully we'll be lucky 'chelle We have a hand-over date...15/10...but I won't hold my breath! http://people-in-glass-houses.blogspot.com/ Re: How to Evaluate Cracks in Poured Concrete Slabs & Floors 8Apr 09, 2008 8:35 pm Even when rio is used in the concrete, they can’t guarantee no cracking.
Temperature has a lot to do with it, the sudden drop in temp then rise again, is generally not good for concrete! Good luck, I know a few clients who have spent a fortune on their polished concrete floors, but haven’t heard how they have held up. Internal and External Building and Colour Consultant Online - Worldwide http://www.denovoconcepts.com Re: How to Evaluate Cracks in Poured Concrete Slabs & Floors 9Apr 09, 2008 9:18 pm 'chelle Well that's good to know - not that we pay more....already knew that - but that they do take more care. Our designer has already warned us that it is almost impossible to guarantee a crack free floor though. Hopefully we'll be lucky There are some very good references at http://www.concrete.net.au/search.php?c ... ded&menu=4 the third handbook down is a very good summary on polished concrete floors. Just as a general point the fourth last handbook covers residential floor slabs and Table 4.1 and pages previous covers the various slab classes - so you can see why H is so much more expensive than M. This reference also has a section on looking after your slab once you've moved in, this is very important, what you do with your garden may affect your slab and any longer term problems. Builders are supposed to put this information in with the drawings for the customer to note, I don't know how often it happens. ***WARNING: SCIENCE CONTENT**** Mish and your designer are right, you can't stop cracking in slabs because as concrete dries out it tries to shrink but because the ground holds it in place stresses build up and it cracks - the stress needs to be relieved. Any slab poured on ground without joints will crack at about every six metres because this is were the stresses due to shrinkage exceed the surface tensile strength - and this is why driveways for example need to be precracked or have sawcuts to relieve the stress. By good reinforcment detailing you can control the cracking by distributing lots of little cracks (or microcracking) along the whole length of the slab but you can't eliminate it. In most cases you won't even see the cracking. Which is why in polished concrete floors you'll generally have a lot of top surface reo. I hope this helps rather than confuses.... mmm....donuts Homer Simpson 1956- Links: Site Costs Ready Reckoner | H1 Addiction Medical Advice | Château TDL: The Backyard Re: How to Evaluate Cracks in Poured Concrete Slabs & Floors 10Apr 09, 2008 9:28 pm Thanks for that, I'll have a look
[quote="to_do_list ***WARNING: SCIENCE CONTENT****[/quote] It's OK...I'll let you in on a secret...I used to be a scientist.....until I had kids and my brain slowly turned to mush 'chelle We have a hand-over date...15/10...but I won't hold my breath! http://people-in-glass-houses.blogspot.com/ Re: How to Evaluate Cracks in Poured Concrete Slabs & Floors 11Apr 09, 2008 9:37 pm Thanks 'chelle if my posts get to techo I'm sure I'll be Moderated just hoping to add to the body of knowledge because I've learn't so much off this forum....
Besides I have a twin personality....Technoboffingeek and Takerofthepiss....just ask Michelle....it's keep's me...yowsah..yowsah..eek..eek...sane! mmm....donuts Homer Simpson 1956- Links: Site Costs Ready Reckoner | H1 Addiction Medical Advice | Château TDL: The Backyard Hello needing some advice. I was about to build my Alfresco and needed a new slab and remove exisiting slab as its not standard. So they start to excavate and jackhammer… 0 10665 my suspicion - some builders, they do usually make 'odd' settings in their site plan / pricing as their standards - being hopeful that first - the initial price is… 9 2443 The spacing of the studs looks pretty large especially for a load bearing wall. 3 11104 |