Geosynthetics solutions company Fibertex
encompasses controlled permeability formwork (CPF) liners – Formtex CPF liners
– designed for concrete surface enhancement in harbour infrastructure projects.
Formtex is a two-layer CPF liner, consisting of a
drainage layer that enables water and air to escape and a filter layer with a
pore size designed to retain cement particles. When surplus water and air is
drained from the surface of the freshly poured concrete during compaction, the
water to cement ratio in the concrete cover is reduced. This results in a
denser and stronger concrete, with a blemish-free surface.
“The main functions of Formtex CPF liners at
harbours and ports are to improve the durability of a concrete structure, to
extend its service life and reduce maintenance costs. Typical applications for
this material include bridges, tunnels and marine structures,” says Fibertex SA
CEO Clive Hitchcock.
Formtex CPF liners, which are suitable for the
rounded shape of concrete elements, are suitable for use in the casting of
bridge pillars and bridge spans, to ensure high quality, durability and low
maintenance of the concrete elements that need to withstand highly aggressive
environments.
He notes that degradation of concrete structures is
normally accelerated by the effects of salt water, high temperature and
increased carbon dioxide levels in the air. However, Formtex’s design features
ensure that project requirements, demanding a service life of concrete of more
than 120 years, are adhered to.
The Formtex CPF liners also reduce the formation of
blowholes and other blemishes on the concrete surface that normally require
extensive deburring after the formwork is removed. The smooth, dense and strong
concrete cover is dust-free and because there are no release agents, it is an
ideal prepared base for further surface treatment or coatings.
The liners, which reduce micro bacterial growth,
are a highly efficient alternative to slip agents for freshwater supply structures.
CPF liners also minimise the penetration of graffiti media, making it easy to
remove from a surface.
Formtex is designed for tensioned, glued or
self-adhesive mounting to vertical or inclined surfaces. Once Formtex is
attached, concrete casting is performed as usual. These liners can easily be
removed from the concrete during formwork striking.
The Fibertex geosynthetics range encompasses
nonwoven and woven geotextiles, gabions and mattresses, drainage pipes and
fittings and erosion control and cellular confinement solutions. The company
also supplies soil reinforcing products, including geogrids and geocells, as
well as geosynthetic clay liners as part of composite lining systems in modern
landfills.
The products are manufactured to consistent quality
standards at all production facilities globally and are supported by a
technical advisory and backup service.
Hitchcock mentions that, apart from harbour projects, the liners are also used in water treatment plants, drinking water tanks, as well as dams and sluices. https://www.engineeringnews.co.za/article/concrete-enhancement-in-harbour-infrastructure-2019-08-02