Wednesday, May 9, 2018


The question came up, how quickly does concrete cure?

Mr. Internet implies that it keeps getting harder for a very long time if you keep it moist.

If you leave it in air it only gets half as strong as it would get if you kept it moist for 28 days.

I guess I will leave those posts alone for a few days before I go back to work on the deer stand.


  1. One would ask:

    How old is that chart?

    There have been incredible changes in concrete in the past 10 years.

  2. Unless something has changed since I was in Engineering school, plain ol' concrete NEVER quits getting harder. We had 80 & 90 yr old samples at Balcones that were continuing to harden.

  3. Need it faster? Add salt, it will drive down the curing time and make it set very quickly. CaCl2 works best. If you use NaCl, don't add too much or it will retard it instead.

    Once you've started pouring it, did you screw up? Is the pour quality critical? You might keep a 5 gallon jug of sugar water around. Sugar prevents cement from hardening at all.


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