Civil Engineering Reference
In-Depth Information
Materials for
Surface
Treatments
Organosilicon
Silanes
Siloxanes
Silicones
Organometallic
Siliconates
Stearates
Inorganic
Organic
Cementitious
(usually
polymer
modified)
Miscellaneous
Bituminous
Oleo -resinous and drying oils
Alkyds
Thermoplastic
and Synthetic
Rubbers
Silicates
Silicofluorides
Thermosetting
Solvented
Acrylic
Vinyls
Acrylated Rubber
Chloinated Rubber
Polyurethane (1 -
pack)
Water Borne
Acrylic
Vinyls
Acrylated Rubber
Styrene Butadiene
Rubber
One Pack
Moisture Curing
Polyurethanes
(may be solvented )
Two Pack
Solvent Free
Epoxies
Polyurethanes
(Meth) acrylates
Unsaturated
Polyester
Vinyl Esters
Water Borne
Epoxies
Solvented
Epoxies
Polyurethanes
Figure 17.1
Coating types
An alternative classification scheme, based on the following categories,
is also useful as it can be related more easily to particular applications. This
approach has been adopted in European Standards BS EN1504-2 and 9 (BSI,
2004, 2008).
i
Materials that impregnate the concrete and that do not depend on the
formation of a significant surface film. These may function in two ways:
•
Penetrants that line the pores with a water-repellent/hydrophobic
layer, relying on surface tension effects to prevent the ingress of
liquids by absorption (capillary action).
•
Sealers that fill and block the pores, thus offering some resistance
to the ingress of liquids under a pressure gradient. A distinct
surface film can be formed if the application rate is sufficient
(usually > 2 or 3 coats) or if the concrete is particularly dense and
impermeable.
ii
Systems that depend on the formation of a continuous layer, thus
shielding the concrete surface completely. Here, the following sub-
division is useful:
•
Coatings, including high-build systems, that have a dry film thickness
up to approximately 1-2 mm.
•
Heavy-duty linings/renders with a greater thickness.
This scheme is used in
Tables 17.3,
17.4
and
17.5
where brief comments are
given on the main performance characteristics of the more common systems
(thick linings and renders have been excluded, to avoid repetition, as they
are often based on similar generic components to those used in coatings).
