Shading. Shade those materials and facilities not otherwise protected from the heat.
Working only at night.
Using Type II or Type IV cement.
Sprinkling. Sprinkle forms and reinforcing steel and subgrade with cool water just before placing
concrete.
Figure 4-15. Mixing water temperatures required to produce
concrete of required temperatures.
Special Precautions
High temperatures increase the hardening rate, thereby shortening the length of time available to handle
and finish the concrete. This means you must transport and place the concrete as quickly as practicable
and take extra care to avoid cold joints when placing it. Proper curing is especially important in hot
weather due to the greater danger of crazing and cracking. But curing is also difficult in hot weather
because water evaporates rapidly from the concrete and the efficiency of curing compounds is reduced. Leaving
forms in place is not a satisfactory way to prevent moisture loss when curing concrete in hot weather because
water evaporates rapidly from the concrete and the efficiency of curing compounds is reduced. Loosen the
forms as soon as possible without damaging the concrete, and cover the concrete with water.
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EN5466
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