Stone mastic Asphalt... not so tough??

247music

Hi All,

I've had SMA laid earlier this year under the belief that it was supposed to be more hard wearing than regular tar and chip.. I have my doubts now though..
It seems any slight turn of a wheel is marking the driveway and in some spots even dislodging large amounts of chip.. I understand that we have had exceptionally warm weather of late but this seems to happen even on colder days and evening times so I'm not convinced that its just the heat. Spoke to my contractor to verify that it was sma he laid and not regular tar and chip and he has confirmed this. He says that it will harden over time and not happen any more.. Is this the case? If so why have i not noticed such marks on other driveways? i cant ask my visitors "could you please reverse out the way you came in?".. I'll come across as a raving lunatic:D.. I dread the oil man coming this year as it is.. I would appreciate any experience people can bestow on me on this matter as I'm no expert in this area.. I've attached some pics of a few spot of damage.. Is it me or does the sma look very loose and pourous.. I dunno, is this the norm?

Four Phucs Ache

Its "porous" texture is normal as where tarmacadam has a tighter smoother structure.

As you say , we have had hot spells so maybe certain spots are thinner and due to their location had more traffic?

landcrzr

What depth was laid, was there a binder course under and what was the sub base like?

enricoh

Doesn't look to be enough tar to bind the stone, might be my imagination but the stone size looks larger​ than it should be too.
If there's a waste piece of it about bring it to your local roadstone tarmac Depot n ask them is it sma

247music

landcrzr wrote:

What depth was laid, was there a binder course under and what was the sub base like?

50mm.. base was solid as stone drive previous for 10 years.. loose gravel removed, levels corrected with fresh stone and compacted.

247music

enricoh wrote:

Doesn't look to be enough tar to bind the stone, might be my imagination but the stone size looks larger​ than it should be too. If there's a waste piece of it about bring it to your local roadstone tarmac Depot n ask them is it sma

Contractor sent me copies of receipts which states sma so looks like it is.. but is there a possibility that it was not rolled enough when laid to compact it? Or could the mix be light in tar as you say.. I dont have a clue as its not an area I'm familiar with..

Kevhog1988

Either not enough binder in it or the contractor was using diesel on his tools

landcrzr

Maybe it went down a little cold, what time of year was it?
As far as the bitumen content is concerned, its a case of a core sample to a lab but this will cost a few Bob and you'll have a hole in your drive.
Do you use a power washer by any chance?

99nsr125

It sure looks like there's not enough binder in it.

http://www.kilsaran.ie/create/product/stone-mastic-asphalt-sma/

http://www.pavingexpert.com/tarmac01.htm

macadam

What company supplied the contractor with this or what area are you in it definitely doesnt look like Kilsaran SMA or Roadstone SMA unless as was previous said it was compacted enough when required.
To me it looks like Open textured macadam, or what we used to call cut back macadam,

micks_address

macadam wrote: »

What company supplied the contractor with this or what area are you in it definitely doesnt look like Kilsaran SMA or Roadstone SMA unless as was previous said it was compacted enough when required.
To me it looks like Open textured macadam, or what we used to call cut back macadam,

Hi macadam are you still around? I dropped you a pm
Thanks,
Mick