Steel Fencing Question

I have a fence that goes over an exsisting Concrete slab. We have a difficult time keeping the gates upright as they are just chained togehter. I want to cut holes in the slab with a concrete saw and set new Metal Pipe posts in the concrete. My question is how big should the pipe be. I have no experience with this and I want to do it right so these post last a long time. Also how far in the ground should I go. We live in Sothern Wisconsin.

Thanks
Joe

You don't say how long or heavy the gates are. Minimum depth of three feet but better to check with county FSA (agent) for frost heave prevention. Deeper is better, bigger is better. Two inch pipe anchored well in concrete should be enough but if your gates are long and heavy???

Use 3 inch fence post. You can cut the slab with a 4 inch core drill. Pound the post in and seal around the slab with caulk.

Bill

You could also weld a flange/baseplate onto the edge of the pipe, 2"-3" dia pipe, use a square plate say 6"x6" on the bottom, stick weld a continuous weld at the base, pre -drill 4 1/2" diameter fastener holes near each corner before welding make a template if you wish, do as many as you need, mild steel is fine, once welded wire wheel off all the mill scale on new steel, clean with solvent and use cold zinc galv spray, so it won't rust anytime soon and then drill the slab with the template and install pipe with a baseplate fasten with a sleeve anchor, wedge bolt, expansion bolt, ie; Hilti, what have you and it's done.

Other way you could lay out the posts, core drill oversize of the pipe diameter, set, and fill with a high strength grout or similar that will bond strong to the metal and the existing concrete, non shrink type material and obtain the same compressive strength as the concrete, though I think the mechanical fasteners would be stronger and easier, + done as soon as you install those fasteners.

Also, be careful with edge distances, hopefully your posts are not too close to any edge of the slab, either core drilling or using mechanical fasteners.

Another option- I had some big landscape blocks made by the redi-mix company-usually used for bunkers- they have forms for their excess concrete and sell those blocks for $25 each. Blocks are 2x2x4. I had them put 3 inch pvc pipe in them, 2 per block. Set up on end, they make sturdy posts for portable fences on concrete slabs. Chain the gates to the blocks, using the holes.