ABSTRACT
All grouting works consist of two sections: ‘drilling of boreholes’ and ‘grouting of substrata’. The boreholes serve to make joints, voids and caves accessible for the grout material. In general drilling costs exceed the costs of grouting. The procedure serves to produce a coherent homogeneous grouting zone. A useful compromise has to be found between the costs and the requirements of proper grouting. Boreholes in rock which are prone to collapse may be stabilized by grouting according to the descending method instead of using drilling mud. The risk exists of designing and carrying out grouting work which proves to be rather ineffective. Collapsing layers are cemented ahead of routine grouting to enable proper packer fixing. Grouting downstage is more costly and time-consuming than grouting upstage. Different from rock grouting the amount of material to be grouted in soil is calculated according to the size of the grouting zone.
