On 2 Mar 2005 06:54:00 -0800, "tomd"
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

OK. Thanks.

I tend to agree with what a couple of others said. Leave the steel
there and use it a a hold-down for projects, either magnetic or tack
welded. Fill in the hole with dirt and lay cement to floor level.

My building was used for a gymnastics school.
The 1/2 inch steel has holes drilled every couple of inches with
extension springs, and a canvas tarp is stretched across the pit held
on each side by the springs . The kids would bounce down the
trampoline doing flips.