I am about to start the same project -- removing a long concrete sidewalk
that slopes the wrong way. I have to be careful because it's next to a
section of new paving blocks that I don't want to damage. The sidewalk
already has a couple of breaks in it, and my plan was to use a diamond blade
in an angle grinder or a portable saw to score the concrete a couple of feet
away from one of the breaks, then use a mason's chisel to deepen the score
line before using a sledge to break it up. I figured once I got the first
sections out the rest would come a lot easier.

Did you try cutting or scoring the concrete before removal or did you just
go out and whack it apart? TIA -- Regards --

"Harry K" wrote in message
oups.com...

bill a wrote:
i've been doing quite a bit of this lately.
you can maybe break it up with a hammer, but i wouldn't try it unless
you
have
a large prybar to get under one end of the slab to lift slightly.
without a
bit of
air gap under the slab, it could be very tough going.
if no big prybar, rent an electric breaker hammer.
btw, the electric hammers are kind of fun.

bill

"RB" wrote in message
...
We have a massive concrete step that I'm going to replace. The
question
is
whether or not I can bust it up with a sledge, in place.

The piece is 3'W x 4'L x 8"Thick.

Will whacking on it with a sledge finally break through that 8"
thickness
and start shattering pieces off?

The reason I'm asking before trying is because, if I can bust it
up, it
will
have to stay in place and maintain function and appearance for a
short
interval until I can figure out how to rig it out there in one
piece.

I'm hoping sledge blows will put fault lines though the mass and
start it
breaking up.



That is the answer if you are going to use a sledge. Pry up and block
one end up an inch or so. The whole trick is to get clearance under it
and put it under at least some stress. Keep hitting a line across the
the block. You don't need to use round-house, full power swings.
Solid blows concentrated along the same line will crack it sooner that
you think. I have removed 3 very solid sidewalks (one 6" thick) this
way, removed a complete set of steps 3 high,and a 8" thick knee high
school foundation including the footings using the same method. The
steps were about 4" thick poured over rock filling.
I broke em up to sizes I figured I could manhandle. Fortunately none
had rebar it it. Be sure to wear a face mask - there is going to be a
lot of fragments flying fast. Something very satifying (as well as
sweaty) to the work. Thrilling to hear a dull 'thud' vice sharp ring
as it cracks.

Harry K