See forepoling

Interference with a natural system that is potentially harmful or unwanted

An overstressed rock condition involving the spontaneous and violent detachment of rock slabs. See also rock burst.

The structure or the end of the structure at the two ends of a tunnel at the interface of the covered and open sections

The entrance from the ground surface to a tunnel.

To start the tunnel excavation at the portal face.

The vertical members of a steel rib or timber support system.

A steel pressure vessel used for transporting concrete. At the point of placement, the concrete is ejected from the pot by use of compressed air.

Number of pounds of powder per cubic yard of rock.

Slang for man who handles explosives.

Pre- bagged concrete or shotcrete mix supplied in bags with all ingredients oven-dried and pre-mixed

A technique of inducing cracks roughly following the periphery of the rock shape to be excavated by the use of closely spaced holes and reduced explosive charges prior to main blasting; a subdivision of smooth blasting.

Brand name of an air-activated concrete placer.

Used mainly in concrete tunnels to temporarily lock a flexible joint, to modify stresses until immersion, or to provide additional strength during transportation and installation.

Measures that are undertaken in order to avoid an environmental impact.

Sum effectively spent to obtain marketable good

The tunnel lining placed to support the ground as the excavation proceeds.

One says this of a project that yields in total more benefits than costs. It is usually applied to financial returns.

Legal division of real-estate

A measure taken beforehand / stipulation