A mine working is a cavity that formed in a mountain range after minerals and rocks were excavated from it.
Depending on the purpose, work with rock is divided into types.
Process Description
Underground mining is different in that its cross section has a closed circle, regardless of whether there is a direct exit to the surface. In addition to underground work, there are those that are carried out on the ground. An open pit has an open cross-sectional contour.
With an underground method of work, it can be:
- mining and exploration;
- capital mining;
- mining preparation;
- rifled;
- mortgage;
- treatment.
Mining, depending on the destination, is exploration and exploitation. The first is used for exploration and search for new deposits, the second - for the development of deposits in order to extract minerals from the bowels. Maintenance works are divided into opening, preparing and cleaning.
Opening excavation is designed to open a mine and provide access to minerals.
Preparatory work prepares the mine field for development, and in the process of clearing the ore, minerals are released.
The type of rock determines whether the development will be in-situ or field. The first is carried out along the reservoir, the second - through waste rocks.
Mine working can be extended and voluminous, which is determined by the ratio between the longitudinal section and the cross-sectional area of the processed rock. Extended, in addition, are horizontal, inclined and vertical.
Open pit is subdivided into trenches, ditches, wells, ramps.
Cross section
The cross-sectional shape in the horizontal method depends on the properties of the rocks and their condition, the direction and strength of rock pressure, the service life and the fastening design.
The vaulted cross-sectional shape is given to a working that is not fixed, as it is close to the shape of a natural vault.
If there is no lateral rock pressure, a rectangular section shape is used. In this case, the working is fastened with wooden, mixed or rod fastening.
Trapezoid shape withstands both vertical and lateral pressure. The mount is made of wood, precast concrete and metal.
The cross section can also be round, vaulted and arched.
The vaulted shape is used for concrete and stonemount.
Arched fastening is used for vertical and lateral rock pressure. In this case, the working is reinforced with various metal arches.
For all-around pressure, a round section shape is best. Coal wells may not be fixed at all. An elliptical section is used if one of the pressure components is much larger than the others.
In the construction of tunnels, hydraulic structures, subways, elliptical intersections with horizontal and vertical axes are used. The shape of the section depends on what the mine working is intended for, as well as on mining conditions. In particular, the shape is affected by the vector of influence of the maximum pressure component, parallel to which the axis of the ellipse is located.
