Have new concrete which I want to split a tractor on

I poured a 5 1/2 inch floor in part of my new machine shed 16 days ago. I believe this last Thursday, November 12th makes it two weeks ago. The concrete does have 7/16" steel rebar on a 2 foot by 2 foot pattern. Used 4000# mix with 1% calcium to speed setting up some. Have had some decent temperatures to help with curing. The tractor probably weighs 14,000 pounds. Has enough time passed that I can put a Case 2090 on the concrete to split the tractor? Need to get into the powershift.

have you been keeping the concrete moist for the two weeks?

Well, If it ain't cured by now it will likely never will cure. Go for it
Loren

Most of today's shop floors have vapor barrier under them and the vapor barrier holds the moisture level for a long time. In an enclosed structure with walls and roof, no hot sun or winds, added moisture is the last thing his new floor needs.
Loren

Yes, I did put a vapor barrier under this concrete which would have helped retain a lot of moisture. When I have poured concrete in the summer I do keep it wet with sprinklers or water under a plastic sheet on top. This time of year with the low temperatures we have in Iowa evaporation is not really a problem, so I decided not to keep it wet. It was covered a few days.

Only if you want to ruin your new floor. Concrete requires at least 28 days to fully cure.

It should be at least 3,000 psi, should be good to go.

Most concrete will hit the mix design strength in 7 days. I have read hundreds of break reports. Most concrete will exceed the design strength by 10-15% in 28 days, especially if the slump is held in range. Go for it, but don’t drop anything heavy.

I think it's risky to do it this soon. Maybe if it was summer but not this time of year especially since it was cold enough calcium was put in the mix. Not only that, do you want to get oil all over your new floor?

use something to spread the point loading. Steel plates,planks or stacked plywood

Your concrete at 14 days should be north of 3,000 psi. That's pounds per square inch. The surface area of your tires will not exceed that limit but a jack stand or pry bar may. Just spread the load out over the surface area of your concrete. Use a 10x10 piece of wood or steel under everything other than your tires and you will be fine.

3X spread the point loading. Assuming that you will block the front and roll the rear, my only point of concern would be the floor jack wheels.

If something bad happens Andy, don't phone the concrete outfit and tell them what some of the YT Engineering crew advised you to do ...... LOL !!!

A couple of years ago, the owner of the local concrete plant told me that after 10 days, concrete will have 90% of it's permanent strength. After 30 days it will have 99% of it's permanent strength.

When we poured the bay door ramps at the new dealership we waited 10 days to drive any thing heavy on them the 10th day I drove a new 2670 up on it and installed the duals did the pre-delvery it was there two days in the same spot,, I had to jack up each wheel to install the duals,, never a issue,, also worked pouring concrete bases for auto gates here we would let the bottom pour set three days then pour the big main one the gates set on then,, 10 days we pulled the forms and set the gates,, did thousands of them later I did some concrete work in the oil filed here one job was to make a crossing over a creek that would old the heavy rig trucks and later the ones hauling the crude out,, we just had the three concrete trucks dump the whole load one at a time in the edge of the water and I used a backhoe loader bucket to spread it out across the 20' crossing water was running the whole time,, two days later we was using it still there today,,

The local company that sold you the concrete should know their product and your local weather conditions better than anyone else can. I would ask them.

Well not being a CONCRETE GUY but had poured my fair share of mud . When my buddy and poured the floor in our shop the first day just he and i poured 32 yrds of 6 and a half sack mix up to inches thick and hand finished it , Two days later after he and i could somewhat move again we poured 36 yds and hand finished it . Four days later myself my buddy and his brother back three loaded coal buckets in the building and his brother being the lightest. of the three with only 118790 my buddy was 132500 and i was 134600 , yes that was gross weights in lbs . We had wire and LOTS of beer cans along with six inches of 57 lime stone for base . This was back in 77 and todate the only crack in that floor was back by the OLD coal furnace , why it cracked there i have no idea but that is where a crack happened , We kept about two ton of coal near it and a stock pile out side where we would park the trucks on nice days and at night when we had really good coal on the good coal fairy would always leave about a ton off each truck . It always seamed that while loading that LUMP coal was always up against the tail gates

My 1 cent's worth on the subject. Around here highway standards for concrete is to wait at least 8 days to cure before allowing traffic on it. Of course they use thick high strength concrete with a low slump factor so their isn't as much moisture in the mix to start with. That low slump factor is what allows the concrete to stand up on its own for street curbing which justs uses a form on the back side. The colder it is, the longer the wait.

Could put some plywood down and under the wheels to spread the weight of the tractor. Plywood or some 2 by's under a jack will spread the load.

After this much time, I'd be more worried about getting oil on the new concrete so put some plastic down underneath the tractor.

By all means call the concrete company but they can't tell you if the concrete crew had the driver add more water to make it soupier and easier to pour which then decreases the strength and increases cure time. Sometimes a short handed crew will add water/increase the slump factor to give them more time to work the concrete on a big pour especially if floating and screeding by hand and having to wheel barrow, shovel and rake a lot. An experienced full crew with a screeding machine runn the width of the pour mud will keep the slump factor lower as they are quicker and more efficient. If pumped in then it could be a little wetter mix.

The final outcome will also depend upon the fill material and how well it was compacted. You should be ok on the rebar. We used to use that 6" remesh wire which doesn't have the strength of rebar. There are varying theories on the need for rebar, remesh, using binding fillers, etc. They also make better filler for sealing the saw cuts that holds up better over time.

You probably watched the crew so you know what you got. The quicker they took the forms off might indicate how confident they were in the strength of the pour and how soon they power troweled it assuming they did.

You might think about putting one of those epoxy coatings on it before you get any oil spilled on it.

Free advice is worth what you pay for it. Whatever you do it's at your risk. Unless you had a testing lab pull samples you really don't know what you have. If you did pull samples have them break one to see what the strength really is. Did you proof roll the fill or have it tested? If you put a vapor barrier down did you put two inches of sand over so the moisture in the concrete has a place to go? So, if you think you've done everything right and feel confident, go ahead. If not, better wait for typical 28 day curing.

concrete needs moisture to keep the chemical reaction of hydration going---we actually put the test cylinders in a tub of water for the 28 days

actually concrete cures forever--but after 28 days the increase is very minimal so that's why 28 day strength is the usual specified strength

According to the Poertlsand Concrete Assoc.

Spraying and fogging
Spraying and fogging are used when the ambient temperatures are well above freezing and the humidity is low. Fogging can minimize plastic shrinkage cracking until the concrete attains final set.

Saturated wet coverings
Wet coverings saturated with water should be used after concrete has hardened enough to prevent surface damage. They should be kept constantly wet.