"Harry K" wrote in message

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.

Yep. Get it off the ground with a prybar, whack it with a 16 lb sledge. It
ain't half as hard as it sounds. I took out a 20'x 2' sidewalk in an
afternoon and ended up with a bunch of nice landscape blocks.

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