My daughter broke her gas fire pit cover. It is made of a cement like material and is somewhat lighter. After some research, I thought it would be interesting if I tried out some goop as the adhesive. It is suppose to hold to everything including cement. The piece area is large, but the thickness is only half inch. I'll wait 24 hrs before I release the clamps. 

 I am not concerned about heat being a problem. They let it cool before they cover it because a vinyl cover goes over the whole thing

If that doesn't hold, maybe Gorilla Glue??

 

Nice Clamps!

That may work also, but there is leverage involved and I would not be surprised if they both fail

 

If ya end up making a new one, use vermiculite and regular portland cement  Lots and lots of vermiculite.   7 to  1 ratio with a galv' welded wire mesh in the middle

I don't expect the goop will do the job, at least not for long, as it's pretty flexible and secondary bonds in concrete  tend to be poor.

 

 

IF it does fail......drill some "dowel" holes into the break.    Cut the heads off the longest nails you can find.   Epoxy them in place.   Use the same epoxy (Hilti makes a good one) along the crack, clamp up and let set an afternoon..

The goof worked and it is very solid, at least for now. I've used it before in places I thought it would never hold or last. It is still there doing good.