Automated concrete form filling 08 Jun 2017

Final tunnel lining with concrete formwork is currently a manual, labour-intensive and costly process. A new automated concrete filling system, Formkret, developed by Kern Tunneltechnik and Putzmeister, will enhance safety, reduce workforce related costs, save on project timelines and allow other work to be carried out on site simultaneously due to its compact structure.

Formkret concrete filling system

A set of two-way valves are integrated into the formwork structure and connected by a single delivery line that links the entire system in sequential rows. The valves switch the flow automatically between both halves, regulated by a Putzmeister concrete pump with an output capacity of up to 79m³/h. As the concrete reaches the optimal filling level in each row, the valves close, re-directing the concrete towards the delivery line, and allowing the formwork filling process to continue sequentially towards the next row. The two-way valve is operated automatically by radio remote-steered hydraulics.

Upon completion of the formwork filling, the entire system can be cleaned in one go by pushing sponge balls through the delivery line with the aid of compressed air. The sponge balls, alongside any surplus material, are safely retrieved with a basket at the end of the delivery line. Maintenance costs are also lower because of the use of pipes, which can withstand higher delivery pressures and have a longer service life than hoses.

This new concrete application solution for tunnels worldwide will be launched at the ITA-AITES World Tunnel Congress taking place 9th to 15th June in Bergen, Norway.