Successful spray robots

BAM Betontechnieken (the concrete technology specialist operating in the Netherlands) is participating in a consortium that is applying a fire-resistant coating to one of the High-Speed Line tunnels between Amsterdam and Antwerp. The work will be finished by the end of March 2005.

The tunnel coating is applied by spray robots (developed in-house) that were previously used with great success on the six-kilometre Westerschelde tunnel (in the southern Netherlands). The spray robots consist of a supply truck, a computer-controlled mortar-mixing unit and a spray arm mounted on the frame of a caterpillar crane. The tunnel wall is first divided into sections that are scanned by a computer. This enables the spray arm to apply the correct thickness of fire-resistant mortar mix with a high degree of accuracy.