By Concrete Canvas – An old brick flume was taking water from a nearby canal. The water course traveled under a Network Rail line and into a river the other side in Bath. To remediate its aging, leaking design, Concrete Canvas ® GCCM* (CC) was installed as a long-term lining system.
The works were carried out by Gardiners for The Canal & River Trust.
CONCRETE CANVAS FOR A BRICK FLUME
The original brick flume was in need of substantial repair. The Concrete Canvas® CC geosynthetic barrier solution provided a cement-impregnated geotextile that would harden on hydration to form a durable, fibre-reinforced, impermeable concrete barrier.
CC can be deployed by hand from man-portable batched rolls or from large bulk rolls mounted on spreader beam equipment for larger projects and where plant is available. The material can be cut to the exact section of any given channel, eliminating waste and accommodating variations in profile. Advantages in this geosynthetic composite solution over conventional concrete include the speed and ease of installation, cost savings, durability, and environmental friendliness.
Site access was via a steep slope of around 40° and through a set of wooden steps. Given the restricted access to the brick flume, CC8TM batched rolls were specified. Neither haul roads nor plant would be needed to install this variation on the GCCM.
Water was diverted via temporary pipes and existing bricks were jet washed. Large voids in the brick flume were grout repaired prior to the installation of Concrete Canvas®.
The channel measured 24m in length and was 1.2m wide. The CC was overlapped in the direction of water flow by 100mm and cut to the required lengths. Shot-fired nails were used to joint/fix the CC at 200mm centres, along with fixing it to the existing brick-work underneath on the edges. The leading edge of the brick flume was grouted to prevent any water ingress. The temporary pipework used to divert the water flow was then removed, providing a natural source of hydration, alongside buckets of water being collected to hydrate the sides of the channel.
Following site preparation, 40m2 of CC8TM was installed in a day by just two people. The installation was considered a great success, as it would have proved to be very costly to use conventional concrete with just two path access.
Though this brick flume project was small compared to some other Concrete Canvas installations, it demonstrated how flexible the use of a Geosynthetic Cementitious Composite Mat can be.
Learn more about GCCM materials, applications, and project references at www.concretecanvas.com.