enclosures are sturdy and reasonably airtight and allow for free circulation of warm air. You must
provide adequate minimum temperatures during the entire curing period. The easiest way to control the
temperature inside the enclosure is with live steam. Unless they are properly vented, do not use carbon-
dioxide-producing heaters (salamanders or other fuel-burning heaters) when placing concrete for 24 to 26
hours afterwards.
FORM REMOVAL AND STRIPPING
Basic Considerations
Careless workers can cancel out the value of good detailing and planning by indiscriminate use of the wrecking
bar. A pinch bar or another metal tool should never be placed against exposed concrete to wedge forms loose. If
it is necessary to wedge between the concrete and the forms, only wooden wedges should be used.
As a rule, wall forms should not be removed until the concrete has thoroughly hardened, but specified curing
should begin as early as possible in warm weather. Ties may be removed as early as 24 hours after casting to
loosen forms slightly and permit entry of curing water between form and concrete. Ornamental molds must be
left in place until they can be removed without damage to the concrete surface. In cold weather, removal of
formwork should be deferred or formwork should be replaced with insulation blankets to avoid thermal shock and
consequent crazing of the concrete surface.
See Table 4-6 on page 4-32 for recommended stripping time. After removing forms, check for concrete defects
and repair all deficiencies.
4-31
EN5466
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