Fixing through Tarmac into concrete

[tramsden]

Hi
I want to fix what is in effect a 1metre post to my driveway. The post is actually a telescope pier. It's 1m x 110mm aluminium post on a 350mm base. The base has 3x20mm cut outs.
The driveway is Tarmac over 4" concrete with rubble below.

What's the best fixing for this scenario

Kindest regards
Tony

 

[Burnerman]

You won't get a good fixing into tarmac....depending how thick the tarmac is, your securing bolts will have to pass right through it.
If its too deep, it would be worth while cutting the tarmac square away, or removing it and adding some concrete to bring the level up again.
John

 

[tramsden]

The Tarmac is about 1.5" I think. It would be so easy to pop in anchor bolts through it and into concrete below.
I did think about removing a square of Tarmac and concreting the space but how well would the 2 concrete area bond?

T

 

[Burnerman]

If you can get your fixings to penetrate into the concrete below then that should be fine......the concrete patch would bond well enough so long as there is a key onto the concrete beneath....some pva in the mix wouldn't do any harm!
It sounds like this is a sort of security bollard you intend to fix? Bear in mind that any vehicle that rolls its wheels over the thing would give it a hard time...
John

 

[tramsden]

Btw is an anchor fitting the best option or a resin one.

Sorry to be so Nieve but what's the difference between all the different anchor types

Thanks again
Tony

 

[Burnerman]

Resin types actually glue in, expanding bolts (a la original rawlbolt) expand as the thread is tightened, gripping further and other types are pressed into the cement when the base is being cast.
All require accurate drilling and hole sizing to some degree.
John

 

[tramsden]

Thanks for the input John.

So in my scenario, which would be best. Resin or expanding anchor?


T

 

[Burnerman]

Due to the depth of the required holes, and the proximity of tarmac, I have to say that a resin fixing would probably be best.
Have a look at the Fischer website for more info.
John