Shop floor- fixing rough concrete ?

Looking at a building where they managed to screw up a section of the floor so bad that rolling a pallet jack or machine on skates over it would be near impossible. Chunks as deep as maybe 1/2 or so out of the floor, spans perhaps 800 sq feet.

Any ideas on repair such that a 20,000 lb machine could still be rolled over the repaired section without cracking it ?

well.... use an air chisel on the damaged areas.
chisel out to sound concrete.
paint exposed areas with neat P.V.A.....let the stuff go off a bit then pour in concrete.
you could also add some of that fibre glass chopped strand to the repair.
all the best ....mark

Sounds like spalling. The mix might have been too wet when they poured it, or too stingy a mix. In either case it will never be as strong as it should be. 800 square isn't very big an area. Break it out and re-pour.

The problem is not related to defective original pour but some some of huge machine they had "glued" to the floor in that area. They did fiberglass work of some sort so perhaps a potrusion machine, or perhaps they spilled alot of resin and damaged the floor scraping up the resin globs ?

Don:

The grouters I worked with for so long specialized in spall repair, along with the other hocus-pocus they did 'way underground in the Metro.

Actually spall repair was the least technical aspect of what they did.

What I am getting at is that in just about any larger city there is a contractor who will bid the spall repair job for you.

The good ones do the job right, there will be no worry about industrial truck traffic or recurring spalls where they did the repair.

Talk to several contractors and arrange to see some of their repair jobs and talk to the owners.

Getting the bids form reputable contractors will also give you an idea of the true cost of the building you are looking at.

It will also give you considerable leverage in negotiating the price you are willing to pay for the building

While you are inspecting the building, do the chain drag test on the floor. You want to know if there are voids under the slab.

If they are large or in bad spots, the same contractor that bids the spall repair might also bid the mud jacking.

http://www.fox-ind.com/
Get the number from the site and call them. They are real helpful and knowledgeable.

How old is the concrete?800 sq.ft. may not seem like a large area but when you're moving a 20,000lb. machine across it,it becomes a sq. mile.If it's not to thick I'd replace that section.

[This message has been edited by ray french (edited 03-15-2004).]

There are epoxy compounds that are mixed with sand that will repair those areas. Getting new concrete to stick to old in thin areas may be difficult. Epoxy should take care of that problem. Fasco, a company in Miami has it, but It must be available elsewhere.

We used to use a product called Stonhard for areas torn up by fork truck traffic. Its expensive, but holds up well.

I have a spalling problem in my shop. I have had several conctrete guys look at it. There are several solutions but the strongest and also the cheapest is to chisle it out and pour a new section. It is still more than I wanted to spend but I don't have any really heavy machines. I poured a 3" slab just big enough to set each machine on. It was cheap and gave me a level mounting surface.

If you find a cheap solution let me know. I was looking at 3.50/sq foot to redo mine.