Browse Forums Paving & Concreting 1 Mar 12, 2020 11:46 am Our builder's concrete guy did not use an isolation joint between about 35m of driveway and house/garage slab. When raised we were told that dowels were used to attach the concrete together to act as a single unit.
My limited understanding is that even with dowels, an isolation joint is still required? And that the dowels need to have an expansion end cap or sleeve. Am I correct? If the isolation joint needs to be added, would it be OK to do away from the house? Because we have brick returns, and I am not confident that whoever cuts the concrete will fully cut into the lower corners where we can not see. Ugly though in an exposed aggregate driveway. Lastly, is 35m too long without an expansion joint? It has control joints/cuts every so often. Re: No isolation joint between driveway and slab, dowel used 2Mar 16, 2020 9:31 pm Sorry to bump this, but could anyone advise whether a driveway/garage slab that has been joined with dowel bars will still need an isolation joint? As in, compressible material between the garage slab and driveway? Re: No isolation joint between driveway and slab, dowel used 3Mar 17, 2020 7:51 am psdillon ...is 35m too long without an expansion joint? It has control joints/cuts every so often. Control Joints are provided at a ratio of No greater than 1:3,etc,etc If you want a better response may I suggest you put up photos and more information Did you not have certified engineering site plan, details, notes? OT, the council uses engineering details for their crossovers, yet home owners ignore details and listen to concretors? Good luck with getting them back in the future Cheers Chris Designer,Engineer (Civil,Const & Envir),Builder,Concrete & Masonry Contract.Struct Repairs Re: No isolation joint between driveway and slab, dowel used 4Mar 17, 2020 7:58 am psdillon Sorry to bump this, but could anyone advise whether a driveway/garage slab that has been joined with dowel bars will still need an isolation joint? As in, compressible material between the garage slab and driveway? An isolation joint is needed as for the Dowel bar connection who recommended that and why? And are you now going to x-ray the slab at a cost of a thousand dollars? Cheers Chris Designer,Engineer (Civil,Const & Envir),Builder,Concrete & Masonry Contract.Struct Repairs Re: No isolation joint between driveway and slab, dowel used 5Mar 17, 2020 8:50 am StructuralBIMGuy psdillon Sorry to bump this, but could anyone advise whether a driveway/garage slab that has been joined with dowel bars will still need an isolation joint? As in, compressible material between the garage slab and driveway? An isolation joint is needed as for the Dowel bar connection who recommended that and why? And are you now going to x-ray the slab at a cost of a thousand dollars? Cheers Chris Tremendous thanks for the response. The concretor did the dowel bar connection of his own bat, because "on his previous jobs too many driveways were lifting". The builder has offered to add the isolation joint. I'm a bit confused how it would be added as the bricks extend past the visible part of the garage slab, and in houses I've seen there is isolation between driveway and slab, but not where the driveway meets the bricks. I've had a look at our engineering, and I can't see anything about an isolation joint to paving, nor dowel bars. Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Full engineering is here if you are interested: https://drive.google.com/open?id=1ja53i ... wofRLJHSS7 Re: No isolation joint between driveway and slab, dowel used 7Mar 17, 2020 2:59 pm I got to speak to our quality inspector today and he made the point regarding the builders offer to add the expansion joint. He said that cutting the driveway would expose the steel dowels and allow it to rust. And if dowel bars were not installed (most likely), then making the cut could result in the rebar being too close to the surface/edge of the concrete. Seems like a no-win situation. Re: No isolation joint between driveway and slab, dowel used 8Mar 17, 2020 6:32 pm And that is why we don't install rebar dowels externally, it rusts->expands, cracking the concrete over time more importantly, the concretor hasn't followed the engineers details and you haven't got photos of what's been done Keep an eye on it over time Cheers Chris Designer,Engineer (Civil,Const & Envir),Builder,Concrete & Masonry Contract.Struct Repairs To my understanding early saw cuts are to control shrinkage cracks, so doing them now would be pointless. Control joints may reduce ugly cracking during periods of soil… 3 9858 Hi all I need a guidance on how far I need to space expansion joints in the concrete driveway and its type (keyway/foam.) Contraction joints are at 3m max for a 125 slab. Thanks 0 10939 Hi, I am planning to select San Selmo reclaimed original for the fascade of my build. I have seen many photos on line of the brick varying from a rustic to a neat finish.… 0 4577 |