# Tunnels

Trimble® Tunnels software is specifically designed for surveying in tunnels. It provides tools to define, survey, stakeout, and report on tunnel operations and guides you through tasks such as marking areas of underbreak and overbreak, and positioning machinery.

Use Tunnels to:

- Define your tunnel
  - Define tunnel components including horizontal and vertical alignments, templates, and rotation, or import a definition from a LandXML file.
  - Define end‑face blast holes and set out positions typically used for bolt holes or for stabilizing pipe umbrellas.
  - Review the tunnel before going underground.
- Survey your tunnel
  - Auto scan cross sections including options to manually measure and delete points.
  - Measure positions relative to the tunnel definition.
  - Set out predefined positions for blast holes, bolt holes, and pipes.
  - Position machinery, typically a drilling rig, relative to the tunnel.
- Output and reports
  - Review auto scanned and manually measured points.
  - Review set out points.

## Using Tunnels

To use Tunnels, you must switch to the Tunnels app. To switch between applications, tap and tap the name of the app you are currently using, and then select the application to switch to.

The Tunnels app includes the full Cogo menu from General Survey so that you can carry out coordinate geometry (cogo) functions without having to switch to General Survey. You can also access some of these cogo functions from the tap and hold menu in the map. For information on all available cogo functions, see Cogo calculations.

When starting a survey you are prompted to select the survey style you have configured for your equipment.

To define and survey the tunnel using the term 'chainage' rather than 'station' for the distance along the tunnel, tap and select Settings / Language and then select the Use chainage distance terminology check box.