Shotcrete-Technology ´06

Shotcrete for tunnel rehabilitation as well as fire protection applied by robotic manipulator

Prok. Bmst. Ing. Günter Vogl, Dipl.-Ing. Bernhard Tatzl, H. Junger Bauges. mbH, Irdning
Dipl.-Ing. Roland Mayr, Degussa CC Austria Ges. mbH, Krieglach

The ongoing discussions on tunnel safety as well as the current condition of many road tunnels in Austria is resulting in rehabilitation and upgrading works for tunnels in the last and coming years. The H. Junger company is dealing with the assessment of the current conditions as well as the removal of damaged or chloride contaminated concrete and rehabilitation by sprayed mortar and final coatings. The removal of the concrete is done by means of high pressure water (jet) with working pressures up to 2500 bar and suitable nozzle systems adjusted for the prevailing conditions. To prevent the construction from failure during fire or of massive damages after tunnel fires additional requirements regarding fire protection have become indispensable. Our company was awarded the first significant contract in Austria for the fire protection of a part of the Lainzer tunnel by the client ÖBB Infrastruktur Bau AG.
A dry mix shotcrete with PP fibres, which was developed for the purpose of fire protection, is used in this project. The application is done by means of the robotic manipulator "Meyco Logica 15". The Logica system is a computerized spray robot for the application of shotcrete and fire protection mortar with a defined thickness and uniformity. The robot is either positioned free in the tunnel on a carrier or, like in this case, working rail guided on a gantry. The main advantage is the speed of application and achieved accuracy of layer thickness.