Underground Mine Construction

the construction of enterprises, such as coal and ore mines, for the subsurface extraction of minerals. The construction of underground mines encompasses the digging of vertical, inclined, and horizontal underground mining excavations and the erection of buildings and structures on the surface. The surface structures and buildings include headframes, hoisting-machine buildings, buildings used for both administrative and general service purposes, machine repair shops, cooling towers, compressor houses, stores, and spur tracks. In underground mine construction, more than 60 percent of the total amount of construction and installation work is performed underground.

In prerevolutionary Russia, underground mines were constructed mainly in the Donets Coal Basin (the Donbas) and the Krivoi Rog Iron Ore Basin. In the USSR, underground mine construction experienced rapid development during the prewar five-year plans (1929–40). Large underground coal mines were constructed in the Donbas, in the Kuznetsk Coal Basin (the Kuzbas), and in Karaganda in Kazakhstan. Underground metal mines were constructed in, for example, the Krivoi Rog Basin and Perm’ Oblast.

During the Great Patriotic War of 1941–45, the construction of underground mines was intensified in the eastern regions of the USSR. In the Kuzbas alone, 24 underground mines were put into operation during the war.

Between 1943 and 1950, the bulk of the work in underground mine construction was devoted to the reconstruction of wrecked or flooded mines in the Donbas, the Moscow Coal Basin, the Krivoi Rog Basin, and the Nikopol’ Manganese Ore Basin.

The further development of underground mine construction was characterized by a greater reliance on specialized equipment and an improvement in the organizational forms of management. Between 1950 and the late 1970’s, numerous underground mines were constructed or under construction in the USSR. They included coal mines (such as the Raspadskaia No. 1 Mine in the Kuzbas, the Krasnoarmeisk-Kapitalnaia Mine in the Donbas, and the Vorga-Shor No. 1 Mine in the Pechora Coal Basin), potassium-salt mines (for example, those serving the Fourth Berezniki Potassium Combine in the Urals and the Fourth Soligorsk Potash Combine in Byelorussia), and iron mines (such as the Oktiabr’skaia-Saksagan’ and Gigant-Glubokaia mines in the Krivoi Rog Basin and the Iakovlevo Mine in the Kursk Magnetic Anomaly).

As a rule, underground mines are constructed under complex mining and geological conditions at depths that reach 1,000 or more m. Such depths are characterized by high temperatures of the enclosing rock, elevated rock pressure, and gas emission. A substantial amount of excavation work is carried out to renovate existing underground mines and to prepare new levels in such mines.

The sinking of shafts is fully mechanized. BUKS-lm drilling rigs are used to drill blastholes. Loading machines are employed to load the bulk rock, and heavy-duty self-unloading buckets with a capacity of up to 5 m³ are used to deliver the rock to the surface. Shafts are usually reinforced with cast-in-place concrete by pouring the concrete mix, through pipes, behind a movable metal formwork.

To put a modern underground mine into operation, 40 to 80 km of mining excavations are made. Every year, construction workers dig more than 360 km of mining excavations, including 25 km of vertical shafts. In 1976, the average shaft-sinking rate with the use of rock-loading complexes was 55 m/month in the coal industry and 43.6 m/month in the ore mining industry. The USSR is first in the world with respect to both the volume and the rate of sinking vertical shafts; a total of 401.3 m of finished shafts are sunk per month. Drilling rigs, rock-loading machines, and entry-driving machines are used to drive horizontal excavations. In 1975, about 15 percent of all excavations at underground mines constructed by the coal industry were made with cutting-loading machines; about 20 percent of all such excavations—that is, 1.5 times more than the planned standard—were made by highspeed techniques. In 1976, the average monthly excavation rate was 59.7 m of crosscuts and drifts in coal mines and 69.6 m in ore mines. The volume of ground removed per month in making excavations of large cross section—for example, pit bottoms and chambers—ranges from 300 to 460 m³.

Underground mines are constructed by mine-construction organizations that are specialized in the type of work performed. The organizations include trusts that sink shafts, make horizontal or inclined excavations, install mining equipment, or construct buildings and structures on the surface. Such organizations belong to mine-construction combines or associations, for example, the Soiuzshakhtstroi All-Union Association of the Ministry of the Coal Industry of the USSR and the Tsvetmetshakhtstroi All-Union Association of the Ministry of Nonferrous Metallurgy of the USSR. The specialized Shakhtspetsstroi All-Union Trust of the Ministry of Installation and Specialized Construction Work of the USSR sinks shafts with the use of special methods, such as the freezing or grouting of rock.

Scientific research in underground mine construction is carried out by such research institutes as the All-Union Scientific Research Institute for the Organization and Mechanization of Underground Mine Construction (Kharkov), the Kuzbas Scientific Research Institute of Underground Mine Construction (Kemerovo), and the Donetsk State Institute for the Planning and Organization of Underground Mine Construction (Donetsk). Cuttingloading machines are developed by the Central Scientific Research Institute of Underground-mining Machine Building in Moscow.

In other socialist countries, large underground coal mines have been constructed in the Polish People’s Republic, underground potassium-salt mines have been constructed in the German Democratic Republic, and large underground mines for the extraction of complex ores are under construction in the Mongolian People’s Republic. Scientific and technical councils for the planning and construction of mining enterprises have been established in the framework of the Council for Mutual Economic Assistance (COMECON).

In capitalist countries, including the USA, the Federal Republic of Germany, Belgium, Great Britain, France, the Republic of South Africa, and Canada, underground mines are constructed, as a rule, by specialized firms.