Concrete drying time

[RobA]

I had concrete ramps poured for my barn. I believe they are 5" thick. How long before I can drive something like an ATV over them? How about a tractor?

 

[beenthere]

I assume these ramps are poured on the ground and not structural concrete "planks" or "beams".

Then ATV probably within a couple days and another one at most for the tractor.

 

[Egon]

seven days.:thumbsup:

 

[RobA]

I assume these ramps are poured on the ground and not structural concrete "planks" or "beams".

Yep, just concrete slabs on the ground.

 

[SPYDERLK]

Did you put in any rebar? If so 7 days is plenty cuz if they crack they will not separate so no big deal. Concrete tends to crack eventually outside anyway, but if w.o rebar I would wait as long as you can stand it [up to a month] to give it a chance to reach a good proportion of its ultimate strength. I have broken up parts of a concrete pouring over time as needed. There is no comparison between 1wk and 1mo concrete.
larry

 

[radman1]

The atv can drive over in 2-3 days. With the tractor, I would wait a week. Both estimates are on the conservative side and your pours are relatively thick at 5".

 

[Larry Caldwell]

Concrete does not dry, it cures. Setting is a chemical reaction that requires water to proceed. If you let it dry out, the curing will stop at whatever point it has reached.

Curing rate depends on temperature, but it will normally reach 50% of final strength in a week, and 90% of final strength in 21 days. Moist curing for 28 days will double the final strength of concrete vs. leaving it unprotected in air.

 

[SPYDERLK]

Concrete does not dry, it cures. [Moist curing for 28 days will double the final strength of concrete vs. leaving it unprotected in air.]

Good. .. forgot to mention that.

 

[Cat_Driver]

They say the Hoover Dam is still "curing".

Here's good article for all to enjoy.
CONCRETE: HARD FACTS. DURABLE STRUCTURES

 

[/pine]

Moist curing for 28 days will double the final strength of concrete vs. leaving it unprotected in air.

what is your source of this information...?

the compressive strength of concrete is relative to the water/cement (portland) ratio...keeping it wet will enhance the curing but it will not likely "double the strength"...