What is the meaning of tunnel face in tunnel construction?

"Face", also known as face, is a term in tunnel construction. That is, the heading face (in coal mining, mining or tunnel engineering) keeps advancing. It is not a fixed surface, but the excavation surface has a tunnel surface, a side wall surface and a vault surface.

"Palm Face" is a folk name. It originally came from a coal mine. The old kiln worker described the coal mining face as "only a place the size of a palm". After a long time, it became a "working face", and later it also referred to the working face of tunnels, wells and mines.

Extended data:

Facial deformation

Microscopically, tunnel rock and soil show inherent rheological characteristics; From a macro point of view, the deformation of surrounding rock in tunnel face also has certain laws, showing unique spatial and temporal effects.

The excavation of the tunnel makes the surrounding rock supporting the tunnel body be excavated, and the cavity appears behind the tunnel face, and the stress of the surrounding rock is redistributed, which leads to the deformation of the surrounding rock in the direction of tunnel clearance.

This deformation includes vertical deformation, horizontal deformation and out-of-plane longitudinal deformation. Usually, according to the spatial effect of deformation, the deformation of surrounding rock of tunnel can be divided into the following three forms: deformation in front of tunnel face, extrusion deformation of tunnel face and deformation behind tunnel face.

The main purpose of setting advance support and initial support in soft surrounding rock tunnel is to restrain the development of these deformations and prevent the surrounding rock from loosening.

References:

Baidu encyclopedia-Zhangzi noodle