Formwork for Concrete Structures by R.L.Peurifoy and G.D- By EasyEngineering.net

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CHAPTER 14
Forms for
Architectural
Concrete
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Forms for Architectural versus Structural Concrete
When concrete is used for structural purposes only and the appearance
of the surface is not of primary importance, the essential requirements
of the forms are strength, rigidity, and economy. This permits
greater freedom in the choice of materials for forms, and the demands
of quality of workmanship in fabricating and erecting forms are not
as great as for forms used to produce architectural concrete.
Architectural concrete differs from structural concrete in that the
appearance or color of the exposed surfaces of the forms may be more
important than the strength of the members. The properties of fresh
concrete are such that it may be cast or molded to produce any shape
that forms can be made. A variety of colors may also be obtained by
adding a color admixture to the concrete mix or by adding a surface
coating after the concrete has hardened.
The surfaces may be extremely smooth or they may be quite rough,
depending on the desired effects. The appearances of large and possibly
drab areas can be improved greatly by the use of recessed or
raised panels, rustications, ornaments, and other designs. Metal molds
can produce concrete having extremely smooth surfaces. A variety of
surface patterns can be obtained using form liners that are placed on
the inside of plywood sheathing. A large variety of shapes is available
from companies that supply formwork accessories. The use of milled
wood forms and waste molds permits the forming of concrete with a
great variety of intricate details.
Because the quality of the finished concrete is limited by the quality
of the forms, it is necessary to exercise care in selecting the materials for
the forms. Also, high-quality craftsmanship is required in building and
stripping the forms of architectural concrete if the desired effects are to
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