Glossary.

Active target unit with a built-in dual axis inclinometer; reacts to a received laser beam and delivers the following values every 0.5 seconds:

- the current horizontal and vertical record of the laser point in relation to the zero point of the ELS (middle of the target);
- the roll angle, the inclination angle and the yaw angle (deflection angle relative to the laser beam);

ELS is permanently installed in the TBM and the current location and height, as well as the tendencies of the TBM are recorded; ELS facilities data communication to the control PC.

The Earth Pressure Balance shield uses the material excavated by the cutting wheel as support medium and does not require secondary support media such as compressed air or suspension. However, conditioning of the ground is generally required.

Lifts and places the segments into position.

Excavation tool in the form of an excavator bucket for partial face excavation.

Chamber and/or rooom directly behind the cutter head.

Excavation tools loosen and crush the soil to be excavated at the tunnel face. They are fixed to the cutter head. Type and number of the tools being used depend on the geology to be excavated. Generally, a distinction is made between scraper tools and cutter disks.

Universal excavation tool for partial face excavation. Depending on the condition of the soil, it can be equipped with an excavation shovel, a bucket tooth or a hydraulic hammer.

Exchange of the excavation tools via the access to the tunnel face (long distance tunnelling, compressed air lock).

The external diameter of a microtunnelling machine can be upsized by attaching the additional so-called extension kit; i.e. in general the microtunnelling machine can be used for jacking of pipes both of the respective standard diameter and of the next larger diameter.