Bricks, Masonry, Asphalt and Concrete - concrete curing concerns

Hello,
Our contractor poured a stoop two days ago when temps were at 90 farenheit. Contractor seemed to do wet curing (he sprayed with water) while here that day and he said he included 1% superset. He did not leave instructions with me to spray after that. Overnight the temps dropped to about 40 or 50 farenheit.

Two days later (today) he came back to pour sidewalk and steps. Still cooler temps 50's and 60's during the day yesterday and today.

Nothing was covered with plastic. Again, he sprayed water over surface, but he didn't ask me to spray yesterday when they were gone, and now as I question him he says I can spray everything at 5:00 today.

But I read that once concrete has cured or is curing, or has become dry, adding water is not a good idea.

Here are my questions:

1. Is the superset enough to offset the extreme heat two days ago when they poured the stoop? Or are the cool temps NOW enough to offset that.

2. Should I spray water over the next few days (how long and how often) or will that hurt more than help.

3. Is my stoop going to crack??? Or do you think it is otherwise weakened by it being poured on a 90 degree day without moistening after they left or the next day? No plastic cover or rugs or burlap.

You can probably tell I have a lot of anxiety about this. We've dumped tons of money into our ailing house and can't afford any mistakes at this point.

Thank you in advance for your advice.

Sincerely,
Dazed&Confused

Ordinarily, concrete is kept wetted for about 7 days for best curing. Periodic spraying with water, covered with straw or burlap or plastic. Perhaps the contractor has a different technique.

Once concrete has set you can't water it too much. The more water and the slower the cure the better and harder the concrete will be.

Thanks for your response. Would you mind clarifying for me?

Once concrete has set you can't water it too much.

Does this mean a wet cure is actually not a good idea? Or are you saying that I shouldn't worry that I sprayed it?

The more water and the slower the cure the better and harder the concrete will be.

Does superset quicken the cure? How can I tell when concrete has cured (they said I could walk on it the next day--is that a clear indicator it is rapidly curing?) So by more water, do you mean the contractor should have used a wet curing method and should have had me spray the concrete?



Thanks,
Dazed

Ordinarily, concrete is kept wetted for about 7 days for best curing. Periodic spraying with water, covered with straw or burlap or plastic. Perhaps the contractor has a different technique.


Thank you very much for your response. What kind of other techniques would his procedure fall under? I have been looking online and everywhere I go it seems the best way to do it is to wet cure, though wet curing can be done in a variety of ways. But if you have any guesses as to what else he could be up to with his method, can you let me know?

What about superset--does it quicken the curing time? Does it add strength to the concrete?

If the contractor did not follow good procedure, what can I do about it? How long before I'll see these steps and porch crack? I live in the upper midwest, where one winter can see numerous freeze/thaw cycles.

I don't understand--he has had exceptionally high ratings in Angie's List. But then, you comment within two weeks of the work, to soon to tell if anything's going to crack.