Page 1 of 1

Posted: Wed Aug 12, 2009 10:43 pm
by kop202
Hi all
I'm using tapered kerbs at the boundary with the pavement.
Do I have to break out the pavement in order to haunch the kerbs before making good to the pavement
or could I use some sort of restraint system and just make good to joint between paving and pavement?
Any offers. I have enclosed a pic so hope link works

http://s769.photobucket.com/albums/xx336/kop202/?albumview=slideshow

Posted: Thu Aug 13, 2009 12:20 am
by Suggers
It looks like you've used invisible ink Blockhead?
I might try and be sneaky in this situation, and cut underneath the tarmac at 45 deg for the haunch, without disturbing the surface? - have I misread, & the paving & pavement are both yours? ???

Posted: Thu Aug 13, 2009 2:12 am
by kop202
Hi
No the pavement is the public highway. Lots of drives Ive looked at the contractor have cut back the pavement haunched up and made good
Is this necessary or do you think a border retaining system would do. The one kept in position by driving in pins.

Posted: Fri Aug 14, 2009 11:35 am
by Tony McC
Lay the kerbs on a concrete bed but use a bond-bridge to ensure full adhesion as you really shouldn;t break into the public footpath.

Posted: Sun Aug 16, 2009 2:03 am
by kop202
Thanks Tony. Sadly Im only a first year apprentice and a bit fick. What is a bond-bridge? :p

Posted: Sun Aug 16, 2009 8:24 am
by seanandruby
Slurry Coat - Primer - Bonding Bridge
Various names are given to this technique and there are almost as many theories as to why it is done. In essence, the underside of the paving unit to be laid is coated with a cementitious slurry just before being laid onto the prepared laying course. While some refer to it as 'slurry'. it is also known as "Primer" and some engineers like to refer to it as a 'Bonding Bridge".

The most plausible explanation for its use is as a bond bridge, that is, an adhesive layer between paving and laying course intended to ensure a firm bond between the two, creating a rigid and firmly bound pavement structure. However, it is also promoted as a method of preventing a 'thirsty' paving unit dewatering the laying course and thereby creating a plane of weakness at the interface between paving and laying course. Whilst this is technically credible, to then use a bond bridge slurry with a semi-dry laying course defeats the logic of using it in the first place!

Whatever the engineering theory, the fact remains that most rigid construction stone pavements are now laid in this way.

The actual 'slurry' varies from job to job. There are a number of proprietary products which all seem to be minor variations to a base recipe of cement, SBR, plasticiser and sulphur fume. Some projects use a simple site-prepared mixture of cement with liquid SBR. ..... Taken from flags and slabs on main index

Posted: Sun Aug 16, 2009 11:31 am
by lutonlagerlout
kop202 wrote:Thanks Tony. Sadly Im only a first year apprentice and a bit fick. What is a bond-bridge? :p
well credit to you, that your on here asking questions fella.
i used this site as a reference for years before i even noticed the forums and it has been an education
LLL

Posted: Sun Aug 16, 2009 3:24 pm
by kop202
Thanks Sean and LLL for your comments. As a newbie and just as a
thought what to do think of PVA ing the underside of the blocks before bedding them on?

Posted: Sun Aug 16, 2009 6:12 pm
by seanandruby
As the script reads liquid SBR with cement to make a slurry. It' no good asking my thoughts when the gaffer has already hinted at what you should do. One thing when you dig out and place your kerbs, if there isn't much of a gap then a good semi dry pack mix, compacted with a stick or some simular tool that fits between path and kerb is a good idea.

Posted: Mon Aug 17, 2009 8:37 pm
by Tony McC
PVA is unreliable in permanently damp environments, which means most pavements. SBR is the stuff: trust me!

Posted: Wed Aug 19, 2009 11:24 pm
by kop202
Thanks for the advice
Popped into Selco and there it was "SBR" .