Shop Floor Problem

Re: Shop Floor Problem

Dave Shombert

>Jerry - THis is a little bit off the mark from what you asked, but here's my experience:

My house was built ten years ago, and the worst mistake I made was having a concrete floor put in the shop. Over the ten years, I painted that thing three times, each time with paint that was specifically for use on concrete. It always flaked off, never lasted more than a few weeks before it started. I thought about epoxy paint, but at least one manufacturer had a disclaimer about that also flaking off of concrete. I also thought about vinyl tile, which is relatively cheap. Finally, a couple weeks ago, I had a guy put down this "engineered" hardwood floor stuff - it's a thin laminate, made out of wood and some other substance(s). Looks like the real thing, but it's just floating on a thin foam pad. The sections snap together in a sort of tongue and groove arrangement. Armstrong makes it, although what I got was Cassen or something. I also got an upgraded pad, and it is WAY more comfortable on my feet. And looks great. And greatly simplifies cleanup, since I no longer need all those fatigue mats. I love it.

Dave Shombert

Elkins, WV

Re: Shop Floor Problem

Brett Sherwood - Richmond, IN

>Hi Jerry,

It definitely sounds like your concrete was "over finished" and the contractor who did the job added water to the top of the concrete to facilitate the final finishing. This pulls the "fines" (the Portland Cement and Sand) in the concrete to the top. This layer flakes off eventually exposing the coarse aggregate in the mix.

This should not affect the structural integrity of the concrete. It's more of a cosmetic problem in an indoor situation. When this happens on a bridge deck we remedy the situation by scarifying the surface -or- water blasting to remove the unsound layer and place a 1 1/2 inch layer of latex modified concrete over the deck to renew the driving surface.

In an indoor situation your problem can either be dealt with in the same manner or overlooked. Take a length of log chain and drag it across the floor in a serpentine/side-to-side orientation. The process will determine quickly if your concrete has structural problems. If the concrete is truly bad "chaining" will reveal the "dead spots" in the slab by producing a "dull sound" over the bad area.

It doesn't take long to learn how to do this, and the results are 100% accurate. I would chain the slab to determine the soundness of the concrete. If no big dead sounding areas are found I would just live with the minor spalling and touch-up paint as needed.

Brett Sherwood

Civil Engineer

Indiana Department of Transportation

Re: Shop Floor Problem

David Eaves

>Hi Brett,

By latex modified concrete do you mean by adding bits of polymer fibres? Also when doing this, is any keying in of the layers recommended? I'm thinking about resurfacing a concrete base at the moment in a garage.

Cheers for any help

David

Re: Shop Floor Problem

David Eaves

>Hi there, hope you get your floor sorted. On a new base we did a while back I made a strong effort to get all the flakey stuff off by brushing the surface and making sure the mix was not too wet. On this surface the Expoy paint has been brilliant, so if you can get a more sound surface I'd still recommend it.

David

Re: Shop Floor Problem

Brett Sherwood - Richmond, IN

>Hi David,

There are no fibers in this material we use on the bridge decks. The latex acts as a bonding agent for the thin layer of concrete to adhere to the existing concrete. The DOW Chemical Company manufactures the liquid latex rubber compound and their website could provide more detailed information on the process.

The concrete has smaller coarse aggregate and is mixed on-site in specialized trucks that inject the latex just prior to the discharge of the material. There are no air entraining chemicals used in the mix. The air entrainment is controlled carefully by the angle of the discharge chute on the truck.

I wouldn't recommend it being done indoors due to the long term odor problems.

Brett

It`s been mentioned here before

Bob Hackett

>Horse stall mats.They`re easier to walk on,damp machinery vibration,offer better traction,easy to cleanup, kind to dropped tools,insulate your feet from the cold slab,the list goes on.

A 4X6 mat is cost comparable to a mid grade sheet of plywood,and far more durable.If it was my shop I`d go to the mat for it(pun intended).Just lay them down and fugedaboudit.

For those who think about such things,they`re made of recycled tires.So you`re helping the environment in your own small way,as opposed to killing yet another unsuspecting tree.Something I`m sure all turners worry about;^)

Mainely,Bob

Re: Shop Floor Problem

David Eaves

>Okay cheers thanks for the answer Brett. The Latex stuff sounds like something to avoid :o)

I'm think to mend the floor I'm going to try and get some of the polymer admix to try and make it more crack resistant, as it will only be a thin screed.

Thanks

David

Re: Shop Floor Problem

Gary Bills in NC

>If you pour concrete over existing concrete with cracks in it, the new layer will crack in the same places as the existing layer.

Re: Shop Floor Problem

David Eaves

>Hi Gary, badly worded on my part in the meaning there. The floor that needs replacing just has surface damage. Mainly from car wheels being turned. There aren't any structural cracks. Hopefully by hacking it up and replacing it with a screed it will increase the wear resistance. The Polymer fibres should hold the microcracks together from the wear.

Cheers

David