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advantage in terms of better health and safety Due to their different nature they are often In terms of health and safety, the resins and
classifications. supplied at closer to equal mix proportions hardeners used generally give the products a
Epoxy acrylate resins are mainly used for
e.g.1:1 to 3:1, compared to Polyester or epoxy higher risk rating.
high strength fixings into concrete, and their
acrylate which are usually 10:1 through to 3:1.
good chemical resistance gives good
They tend to be slower curing and exhibit Hybrid systems
performance, even in damp concrete.
virtually no shrinkage, which typically gives Some manufacturers market blended
Epoxy acrylate styrene-free products offer
them considerably better load performance. ‘hybrid’ systems which use cement as an
an excellent level of performance and many
The low shrinkage also makes them more additional component. The incorporation of
anchors using this type of resin are available
suited to use in a diamond cored hole, or for a cement in one component and water in the
with European Technical Approvals (ETAs).
fixing with a large annulus. The slow curing other may increase performance.
A special type of polymer similar in
performance to epoxy acrylate is a urethane
can also be advantageous in hot climates and
acrylate. Typically, this type of polymer tends
also for reinforcing bar, where the slow cure Conclusion
to give a tougher material but may have
gives more time for the injection of material The informed selection of resin anchors is
reduced chemical resistance.
and placement of the bar. very important to ensure safe and long lived
There is even more choice when selecting fixings. This selection can be difficult when the
Pure epoxy
the materials used in pure epoxy formulation properties of the different types of resin are
Pure epoxy products are made from an
and the expertise of the manufacturer not fully understood. Once this is clear
epoxy resin and a hardener (usually amine
becomes even more important. however it enables the best and most suited
based). They cure by a different “addition
Pure epoxy products typically have good product to be used. Once a particular type has
cure” mechanism from polyester or epoxy
chemical resistance and excellent adhesion, been selected it should only be changed if the
acrylate and as a result they lend themselves
and can be more versatile than polyesters. key application characteristics are still satisfied
particularly to slightly different applications.
Their low temperature curing tends to be by the proposed alternative.
Complete mixing of pure epoxies is vital, this
worse and although some formulations are
is easily achieved with the mixer nozzles of
capable of slightly lower temperature curing
most proprietary systems but more difficult
they are generally not recommended for use [1] See the “Delivery Systems for Resin
with bulk mixed types [1].
below +5°C. Bonded Anchors.” Article on pages 74-76.
NEWS
www.fixingscfa.co.uk
Established in 1979 the Construction Fixings Association last year Access Specialists. It deals with all the special fixing requirements of
registered as a non-profit making company in its own right. this industry and has a new test regime to help determine allowable
General manager, Mark Salmon explains, “CFA activities will continue loads when no safe load data exists and proof loads to check that
as before, except that the freeing of resources facilitated by the fixings have been installed correctly.
change allows it to be even more active”.
Information on the CFA website includes other articles to those
The CFA enlarged its membership last year as ITW Construction published here, including one tackling one of the most awkward
Products joined existing full members: fischer fixings sytems, Hilti materials to fix into – Plasterboard – and another considering the
Great Britain, 2K Polymer Systems, Simpson Strong-Tie Leibig and subject of Hand Arm Vibration Syndrome.
Rawl Fixings.
Additional Sample Method Statements are aimed at helping
The Association also, for the first time, extended associate contractors ensure their operatives are installing anchors correctly
membership to selected fixings distributors through its Approved and complement the pictograms on packaging. Five new statements
Distributor scheme. An “Approved Distributors” page on the cover different resin anchoring systems.
website helps users to find their nearest distributor. Distributors
interested in membership should contact Mark Salmon at There are also more Sample Specification Formats for specifiers to
info@fixingscfa.co.uk. help them give contractors all the information they need to ensure
they get hold of the right fixing and install it to the correct
CFA’s most recent Guidance Note “Anchors for Steeplejacking” was parameters. These are word documents for easy transfer into project
developed jointly with the Association of Technical Lightning and documents.
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