GROUTING TECHNIQUES

In granular soil:

• Grouting with tubes-à-manchette (TaM) with annulus grout

In sound rock:

Upstage grouting: Procedure of drilling a hole to full (required) depth in one operation and grouting from the bottom of the hole towards the surface in successive stages, by setting a single packer at predetermined depths.

In weathered and unstable rock

Downstage grouting: Procedure of drilling a hole to a limited depth, setting a single packer and grouting the hole, per- mitting the grout injected around the hole to set sufficiently to prevent it from entering into the hole when the hole is cleaned.

• Re-drilling through the hardened grout

• Drilling the hole to the next deeper stage

• Setting the packer at the bottom of the previously grouted stage or as directed by the Engineer and grouting of the new stage

Tightening and seepage mitigation

Grouting underneath dam and dike foundations: Granular soil

• Pore permeation grouting with tubes-à-manchette (TaM)

• Filling of soil pores in order to reduce the permeability and

• to provide a seepage barrier underneath the (coffer-) dam foundation

Curtain grouting underneath dam and dike foundations: Rock

• Fissure grouting

• Grouting of fissures and cracks of the rock to provide a seepage barrier underneath the dam foundation