Method of supporting and sealing excavation surfaces in the compressed-air-assisted driving of galleries and tunnels, and digging tool for applying this method

摘要

In a method for supporting and sealing excavation surfaces, in the compressed-air-assisted driving 3 of galleries and tunnels by the application of a clay- containing composition which penetrates into the soil of the working face 7 and forms a filter cake 10, the clay- containing composition is a clay-in-water suspension applied with the aid of one or more injection nozzles attached directly to the digging tool 4 and following immediately behind the latest excavation in the form of injection jets 9 to the excavation area 7a just exposed by the digging tool 4, so that the area 7a of the filter cake sealing and supporting the working face 7 removed by the digging tool 4 in each case is replaced by the filter cake section formed from the new application. A digging tool 4 for implementing the method is described. IMAGE