oceanobob
Senior Member
My question has to do with using a hydraulic powered breaker on a mini-excavator or a backhoe. In the past we have tried the breaker on the backhoe and it made the slab look like swiss cheese, and it also (undesirably) pushed the concrete cone out the underside well into the subgrade, making the helper unhappy when they had to rake it out.
*
So we decided we needed a smaller breaker so we asked the rental yard to equip the Kubota KX41-3 (2008) with a breaker. This is a machine with 'expando' tracks and a 'less than fascia board height' rollcage. Guess what - it can make swiss cheese too!.
To explain, the tip punches a hole in the slab, there are no cracks emanating outward and we have repeatedly read Do Not Pry or You Will Cry. We end up with a slab that has all these holes, it is quite weakened and pulls up in chunks when one goes back over it with the toothed bucket. Is this the typical result or is there a technique we are missing? And yes the cones are pushed into the subgrade. If we operate a pavement breaker we get sore and the concrete breaks without punching through. We peel off chunks like peeling an onion.
I enclosed photos, but I neglected to show the swiss cheese effect.
FYI The job was to remove these "forklift ramps" that were to enable traversing the 18" step in the floor slab elevation. They weren't necessary since the forklift can accomplish the same by driving outside which is ramped, not stepped.
*
So we decided we needed a smaller breaker so we asked the rental yard to equip the Kubota KX41-3 (2008) with a breaker. This is a machine with 'expando' tracks and a 'less than fascia board height' rollcage. Guess what - it can make swiss cheese too!.
To explain, the tip punches a hole in the slab, there are no cracks emanating outward and we have repeatedly read Do Not Pry or You Will Cry. We end up with a slab that has all these holes, it is quite weakened and pulls up in chunks when one goes back over it with the toothed bucket. Is this the typical result or is there a technique we are missing? And yes the cones are pushed into the subgrade. If we operate a pavement breaker we get sore and the concrete breaks without punching through. We peel off chunks like peeling an onion.
I enclosed photos, but I neglected to show the swiss cheese effect.
FYI The job was to remove these "forklift ramps" that were to enable traversing the 18" step in the floor slab elevation. They weren't necessary since the forklift can accomplish the same by driving outside which is ramped, not stepped.