Sept 25 maybe?

9-25-15

I got up at 4:33am.  The alarm was set for twenty minutes later.  I went to work to do some preparatory work for a 7 am concrete pour. I grabbed some samples from the aggregate pile to get moisture samples for the 7 am pour.  As soon as I put the samples in the oven from the sand pile and the rock pile, it started raining.  Moisture hides in the aggregate.  In the sand there could be 8 gallons of water hiding.  In the larger aggregate there could be the same.  The mix design has a designated water to cement ration that is not supposed to be exceeded.  Usually it's around .4.  That ratio often means around 32 gallons of water is allowed in a common mix design for one yard of concrete.  Everyday here the rain and or sun changes the amount of moisture hidden in the aggregates.  Its numbers, its very boring, but I'm forced into it, and I kind of like the math part of all of it. 

The higher the water cement ratio the weaker the concrete.  There is an engineering firm in Seattle that my company and our clients company has hired to actually do the mix designs.  They over did them.