On May 16, 7:33*pm, Joe wrote:
On May 16, 5:12*pm, Bob wrote:

snip

The fact that the original bolts failed makes the chances of getting a
good anchor with expansive bolts risky. If the concrete was new and
well cured it would be different. A much used safer technique these
days is to drill and clean the holes out and install stainless steel
studs bedded in epoxy. There are several companies supplying material
for this and the end result is far more permanent than Tapcons or
Redheads from a corrosion standpoint. *The cost is a bit more than the
expanders, and there is a wait for cure time. Also, low temperatures
mean waiting for better weather.
This technique is frequently used for repairing rusted out toilet
mounts on slab foundations.

Joe

OP-

I would concur with Joe's comments & suggestion. Expansion anchors
work by applying "expansion" forces to the concrete & can crack the
concrete if there isn't enough edge distance.

I recommend SIKA AnchorFix #1 or #3. Number 1 is super fast set, gel
in 3 to 5 minutes, cure in 1 hour. Number 3 is much slower, 1 hour
gel, 24 hour cure.

If you choose Number 1 be ready and prepared to set all the SS rods
QUICKLY....otherwise the product will harden in the mixing nozzle!
And you only get two nozzles per cartridge.

The nice thing is, they work in a standard caulk gun.

In SoCal, SIKA products are available at HD.

I would suggest minimum 3/8" SS threaded rod. www.mcmaster.com if
you cannot get it locally. Or use some fully threaded SS bolts & cut
the heads off.

As Joe mentioned, low temps will slow the cure but with the #1 this
would be an advantage.


cheers
Bob