The principles of proper concrete placement include--
Segregation. Avoid segregation during all operations from the mixer to the point of placement, including
consolidate the concrete, working solidly around all embedded reinforcement
and filling all form angles and corners.
against or hardened concrete, make sure that
a good bond
develops. Use of a bonding agent is usually required.
Temperature Control. Take appropriate steps to control the temperature of fresh concrete from mixing
through final placement and protect the concrete from temperature extremes after placement.
Maximum Drop. To save time and effort, you may be tempted to simply drop the concrete directly from
its delivery point regardless of form height. However, unless the free fall into the form is less than 5 feet,
use vertical pipes, suitable drop chutes, or baffles. Figure 4-6 on page 4-14 suggests several ways to
control concrete fall and prevent honeycombing and other undesirable results.