temperature is too cold, heated aggregate and warm water are used to bring the concrete
temperature up to an acceptable level. If the temperature is too hot, ice water may have to be
used. The air temperature is normally 10F above the concrete temperature. You will be
performing this step as you proceed through step 6.
Step 6a. Determine the maximum concrete pressure. Estimate the concrete temperature
(step 5) first. Then refer to Figure 1. Use a straight edge to be as accurate as possible when
using the graph. Compute as follows:
Enter the bottom of the graph at the position where your rate of placing is located.
Move up vertically until you intersect the correct temperature curve. Estimate as
closely to the temperature range as possible.
Move to the far left side of the graph and estimate as closely as possible to the correct
pressure number. It reads 100 pounds per square foot (psf). This number is the
maximum concrete pressure.
Rate of Placing (FPH)
Figure 1. Maximum Concrete Pressure Graph
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