Civil Engineering Reference
In-Depth Information
Common generic types
Main performance characteristics
Cementitious, polymer-modified
Generally ~ 2 mm thick
(2 coats)
Supplied as two-pack systems (blended
cement/fine fillers and aqueous polymer
dispersion) or as one-pack (blended
cement/filler /redispersible powdered
polymer that is mixed with a specified
quantity of water)
Generally provide excellent barrier properties (water, chlorides, carbon dioxide, oxygen)
Relatively low resistance to moisture vapour transmission
Generally unsuitable for exposure to strong acids but can provide some resistance to
sulphate attack
Can possess a useful degree of flexibility
Good durability under a wide range of service conditions (including immersed and below
ground)
Reasonably tolerant of various surface/application conditions; temperature extremes may
require special precautions or limit use
Acceptable maintenance requirements
Silicates
Filled, pigmented systems
(much simpler products are used as low-
cost dust-proofers)
Reaction with the concrete surface assists
adhesion
Excellent durability as breathable and weatherproof decorative coatings
Some anti-carbonation properties
Resistant to some chemicals
Reasonably tolerant of various surface and application conditions
Easy to maintain
Solvent and water-borne thermoplastics
and elastomers
Physically drying
Formulations and performance vary
widely
Can provide excellent barrier properties (water, chlorides, carbon dioxide) and good
breathability
Some systems suitable for exposure to aggressive chemicals
Good durability and retention of appearance
Generally not suitable for immersed/below ground applications or demanding abrasion
resistance
Can maintain a barrier when applied to some cracked concrete (fibre/fabric reinforcement
may be required)
Can be applied under widely varying conditions with relative ease (particularly when
solvent-borne)
Good surface preparation required - often need a fairing/levelling coat and/or primer
Relatively easy to maintain
