Mounting a larger sculpture

["Carl & Jody Wright" <cjwright@xxxxxxxxxxxxx>]

Hi,

I am a sculptor that will soon be ordering 2 limestone
blocks that are 3'w x 4' d x 8' tall.  They will weigh 5
tons each.  I will be mounting them vertically  via 1
1/2" diameter brass rods and sockets to a 4' x 4'
concrete pad.  My question is what shape pediment should
the pad be? How deep should the pediment be installed in
the soil if only the top 1" will peak above the surface?

I have been told by people that work with concrete all
day that a block that is 4' x 4' x 15" tall is all I
need.  That sounds woefully inadequate.  I would think
that would tip over.  If they tip over then the rigging
company has to come back and charge me again which I
would rather avoid.

I thought it should have a bigger base than top, like a
pyramid missing the top third. I am in a quandary.

Can you give me some advice or suggest anything or a
book that could help me estimate the size, concrete
needed, or the preferred method of making a concrete pad
to hold 5 tons?   Thanks loads.

Carl Wright
Martinsburg, WV