how big a pad ?

[Gregory OConnor]

If you prepare a compacted base, 4 inches of concrete is good. if the
bace gets wet and or is not properly compacted, even 10 inches of
concrete is not enough. monolithic parimiter footings are best to be
chanfered at 45 degrees to the center. if you plan on doing that much
of a parimiter pour, two rows or rebar atop each other with 4 or 6
inches between them and 3 inches of mud above/below will give you
truss support.

To dictate where stress will crack a concrete pad, finishers score a
1/2 inch lateral indent across the expanse of the pad "Joint". When
mud is poured on the prepared subgrade it is important to not allow
rebar or somthing as simple as a droped form board to cast a lateral
imprint that will do the same as a score joint atop of the pad.

At the parimiter forms a simple 4 inch line from an imprint of a rock
will give future traffic a place to start a crack. Kinda like making
a cut in cardboard to rip it apart

I think 6x6 wire placed in the center of the mud makes the strongest
pad possible.

GregoryO'Connor
94ptRomolandCa