Conductivity

A measure of the ability of a solution to carry an electrical current. conductivity varies both with the number and type of ions the solution carries.

Conduit

A broad term that can include pipe, casing, tunnels, ducts or channels. The term is so broad that it should not be used as a technical term in boring or tunneling.

Cone

The section between the top of a manhole wall and chimney or the frame. The diameter of the manhole is reduced over the cone section to receive the frame. The cone section may be concentric or eccentric.

Consolidation

The gradual reduction in the volume of a soil mass resulting from an increase in compaction.

Contact Grouting

GroutingThe process of filling voids or modifying/improving ground conditions. Grouting materials may be cementitious, chemical, or composed of other mixtures. injected into the void space between the jacking pipe and the ground after the drive is completed.