Breaking up concrete - proper technique?

[robmorgan]

Hi all,

I recently pulled down our garage in order to reclaim the garden and am now left with a fiendish 24ft x 10ft x 6" thick slab of concrete to break up and remove.

I bought an 18kg breaker having been advised it would be up to the task. I've just had a go and progress is demoralisingly slow. I've done maybe a square foot in about half an hour.

The concrete I'm dealing with has stones / hardcore mixed in with it. Is that normal and should the breaker be able to deal with it? The chisel is starting to look blunt already!

The breaker came with a flat and a point chisel. I've been using the flat one so far. Under what circumstances should I use one or the other?

Is there a "proper" technique? I mean, should I be chipping away a sliver at a time, inch by inch, or should I try and carve out a decent sized slab and prise it up?

Any pointers would be greatfully received... Perhaps it's just the wrong tool for the job and I should hire something more heavy duty?

Thanks,

Rob

 

[Alastairreid]

View media item 10068
sorry couldnt resist
maybe you should go for a heavier breaker!

 

[breezer]

no use th pointed one, it applies the same pressure in a smaller area so it breaks it up.

have you not seen a JCB* breaking up the motorway? although the thing on the end is big, its still round and pointed

* other brands of back hoe excavators are available

 

[robmorgan]

no use th pointed one, it applies the same pressure in a smaller area so it breaks it up.

Ah, that might help (as would a JCB!), I'll give it a try, thanks.

What's the flat one for?

 

[noseall]

18 kg breaker is not man enough, no where near.

You need a heavy duty breaker (30 kg's ish) or a hydraulic two-part compressor and breaker.

http://www.tooled-up.com/Product.asp?PID=108352

 

[mikric]

I recommend hireing one of the two stoke petrol breakers (they rock)
http://www.hss.com/g/2116/Heavy-Duty-Breaker-2-Stroke.html
I have removed 600mm foundations with one before, fantastic tools.

 

[Thermo]

as noseall says you need a bigger breaker for a start. On thick slabs we normally stitch a line of holes across the slab in chunks about 1-2 feet wide. that will ause it to crack and then you can lift it up with a decent pry bar. Once you get the technique its quite easy. Just listen for that satisfying change of tone when the concrete cracks as you drill through it

 

[joe-90]

Thermo's method sounds good. Can you use an sds drill to make the perforations?

 

[Thermo]

not if you want to get the concrete up before your pushing up daisys!