concrete can use a sledgehammer break
If your concrete is 4 (10cm) thick or less, try using a sledgehammer. 1  Start at a corner or edge where possible. 2  Keep in mind that the lateral strength of concrete increases with thicker cross sections. 3  You may find that undermining, or removing soil from beneath the slab will help you it break away more easily. Only use a chisel point bit to break up concrete. 2  This concentrates force for the best results. 3  Let the weight of the machine do the job; it's not necessary to add force by pushing down. 4  Forcing the bit will cause damage to the machine and possibly wedge the bit.