Last year Concrete Canvas was listed as the second fastest growing manufacturing company in the Sunday Times Fast Track 100. With development into new products and ranges it’s an exciting time at the company.
Concrete canvas is quite simply concrete on a roll. Its developer Concrete Canvas started life as a company in 2005 and is celebrating its 10th birthday this month. The firm initially started out by designing rapidly deployable inflatable but durable shelters for the developing world. However it was soon clear that the market for the product went far beyond this and it began to develop the product which is being sold around the world today.
The material itself is a three dimensional fibre matrix impregnated with a high early strength concrete powder. On one side of the fabric there is a PVC membrane giving it a waterproof backing and on the other is a tight weave polyester, through which the concrete is hydrated. The 5mm to 13mm thick, flexible canvas is delivered to site on rolls and is simply unfurled into place, sprayed with water and then left to set. It takes 24 hours for the concrete to cure after which it can be put into use.
“After 24 hours the fibre matrix is locked within the concrete and provides the tensile reinforcement,” says Concrete Canvas director William Crawford. “It also prevents cracks from propagating, so if it does fail you don’t get catastrophic failure, just local deformation.”
Tight control of the density of the concrete which is impregnated into the fibre matrix ensures that the void ratio, or the air space within the dry concrete canvas, limits the amount of water which can penetrate the material. This allows the water cement ratio to be controlled and means that the canvas cannot be over-hydrated. As a result it can even be laid under water and will still set. Accelerated environmental testing has given the product a life of 50 years.
At present the product has predominantly been used to rapidly line drainage channels, to make bund linings for the petrochemical industry and to provide erosion control to slopes where the ground is inherently stable.
And it can be seen why the product is so well suited to these applications. It is extremely mouldable and versatile, quick to lay and requires very few tools and site equipment to carry out the work. With the PVC backing, the material has an inherently high level of permeability to water and in the case of contaminated liquids, the watertightness can be increased by thermally welding the PVC sheets together.
Crawford says that new products are in development all the time.
“We are developing a huge range of products including the types of fibres which go into the product – substituting the fibre with high tensile fibres, fibres with improved fire rating, new types of backing,” he says.
“We put a huge amount of resource in R&D we see it as central to what the business was set up to do and we know there’s a lot of value for what the product can do.”
As if to prove the point, Crawford adds that the industry can expect a new product from the company shortly. It appears that we are only just beginning to understand the potential of this innovative new product.