EPB

Earth Pressure Balance

EPB Machine

Earth pressure balance tunneling machine, by which mechanical pressure is applied to the material at the face and controlled to provide the correct counterbalance to earth and groundwater pressures in order to prevent heave or subsidence. The term is not applicable to microtunneling systems for which the primary counterbalance of earth and groundwater pressures is supplied by pressurized slurry.

Epoxy

Resin formed by the reaction of bisphenol and Epichlorohydrin.

Equalizer

A culvert placed where there is no channel but where it is desirable to have standing water at equal elevations on both sides of a fill.

Erosion

Deterioration of a surface by the abrasive action of moving fluids. This is accelerated by the presence of solid particles or gas bubbles in suspension. When deterioration is further increased by corrosion, the term “Corrosion-Erosion” is often used.