Concrete Surrounds
Concrete surrounds
Cotterill Civils have pioneered our own unique way of surrounding a GRP tank with concrete.
The perfect concrete surround will have no voids in it, it will be uniform all the way around the tank, it will not impose excessive loads on the tank whilst it is being placed and it will be strong enough to anchor and support the tank for life.
Due to a large tank’s huge natural buoyancy, it is normally recommended that low slump or semi dry concrete is used to reduce the buoyant force.
The problem with semi dry concrete is it is difficult to compact. The use of vibrating pokers is prohibited as this could damage the tank. Health and Safety rules prevent us entering the excavation to manually compact concrete.
The problem with wet or high slump concrete is its huge uplift force imposed on the tank. Concrete being far denser than water means to successfully ballast a tank, far more water is needed inside the tank than the concrete level outside it. This again imposes a loading on the tank from the inside out, which could damage it.
We have developed a unique way of using high slump concrete to surround a GRP tank without imposing excessive loads on it and getting a uniform, self compacting “shell” around it.
You can find out more by contacting us.