Despite the recession in the construction industry, one niche sector is doing very nicely, thank you. That sector is sprayed concrete. Tunnel construction, especially Crossrail, has contributed greatly to the amount of current sprayed concrete activity but concrete spraying has another, less well-publicised, growth area – the construction of skateboarding parks. One of Camfaud’s most recent skatepark contracts was at Thrapston, Northamptonshire for Wheelscape Skateparks.
To pump and spray the concrete, Camfaud supplied a mobile boom pump – Putzmeister BSF 20-4.09H concrete pump. The boom was piped up with the standard 125mm pipeline which was then reduced down to 100mm and then further reduced to 50mm to accept the spraying hose. The concrete was discharged directly from the hose for the top slabs and the low-gradient sections. When the steep gradient walls were concreted, the spray gun with compressed air inlet was attached to the end of the hose and the concrete was sprayed onto the walls.
The concrete pump operator worked alongside the nozzleman; the pump operator controlled the concrete pump output and the nozzleman controlled the air injection to give exactly the spraying characteristics required. Once each section was concreted, the finishing crew set to work, screeding the concrete to the desired level using a curved timber screed, ensuring that the shape and depth of concrete were correct and then working the concrete to give a smooth, dense finish.
This hard-polished finish ensures that the skatepark users will experience the best surface on which to practice their art. Concrete for the Thrapston skatepark was supplied by Bardon Concrete from their depot in nearby Wellingborough. This contract is featured in the July/August 2013 of Concrete Magazine – the magazine of The Concrete Society.