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Canadian Standards Association
Precast concrete — Materials and construction
November 2009
4.4.2
Project samples shall be submitted with sufficient information for the owner to assess the quality and
expected performance of the concrete in the sample.
4.4.3
All finishes shall be carefully assessed and detailed with regard to controlling the effects of weathering.
Note:
For special weathering considerations, see PCI MNL-122.
4.4.4
The shape of a sample shall resemble the shape of the actual casting. Flat samples shall be used only for
flat castings. The size of a sample shall represent the maximum size of the aggregate to be used and shall
allow for realistic placing of the concrete and the accurate expression of detail.
Note:
Unavoidable segregation in finishes that use mixes with a large colour difference between the coarse aggregate and
the sand and cement matrix will produce noticeable colour and texture variations.
4.4.5
The concrete placement and consolidation method used to make samples shall be representative of the
intended production method.
4.4.6
Samples shall be supplied for each of the finishes for a project and all samples shall be clearly identified. A
reference sample shall be cast using formwork, concrete, and vibration typical for the project. The
reference sample shall be viewed from a distance of 6 m. Once accepted, the reference sample shall be
identified and used for comparison in assessing compliance with the specified finish.
Note:
Samples with special architectural features representative of items that are installed and viewed at eye level might
require review at closer distances.
4.4.7
The first production units shall be reviewed by the owner before regular production continues. Such units
shall be properly marked and serve as acceptance criteria for the balance of the project. They shall remain
identifiable, even on the building, until final acceptance of the project.
5 Cements, supplementary cementing materials, and
colouring materials
5.1 General
Cements and supplementary cementing materials shall comply with Clause 4.2.1 of CSA A23.1 and
Clause 5.2
of this Standard.
When uniformity of colour for all or part of a project is desired, each cementing material used shall be of
one type and from the same mill. This requirement shall apply whether a single cement or a mixture of
cementing materials is used.
Notes:
(1)
The characteristics of special cements should be investigated before use.
(2)
Some suppliers will provide cement that falls within guaranteed percentage colour variations.
(3)
When a mixture of white and grey cements is used, uniformity is normally improved by increasing the percentage of
white, but the grey tends to dominate.
Licensed for/Autorisé à Jed Friesen Sold by/vendu par CSA on/le June/18/2015.
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Le stockage, la distribution ou l'utilisation sur le réseau est interdit.