shaft
Quick Summary
A shaft is essentially a vertical tunnel, primarily constructed by the mining industry for accessing ore, ventilation, and material transport. These shafts can reach depths of several thousand feet. In public works, they are typically shallower and avoided if possible due to high costs. Shafts are also used for penstocks, missile silos, and storage.
Construction challenges include ground and water conditions, which are more severe in vertical excavations. Most shafts are concrete-lined and waterproofed. They can be sunk from the surface or raised from below if an existing tunnel provides access. Modern methods include slurry trenching, freezing soil to support walls, and large-scale drilling techniques adapted from oil extraction. Raise boring, a mechanized method, significantly speeds up shaft construction.12
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tunnels and underground excavationsā¦opening is usually called a shaft. Tunnels have many uses: for mining ores, for transportationāincluding road vehicles, trains, subways, and canalsāand for conducting water and sewage. Underground chambers, often associated with a complex of connecting tunnels and shafts, increasingly are being used for
Read Moreā¦opening is usually called a shaft. Tunnels have many uses: for mining ores, for transportationāincluding road vehicles, trains, subways, and canalsāand for conducting water and sewage. Underground chambers, often associated with a complex of connecting tunnels and shafts, increasingly are being used for
Read More- tunnels and underground excavationsShafts
The mining industry has been the primary constructor of shafts, because at many locations these are essential for access to ore, for ventilation, and for material transport. Depths of several thousand feet are common. In public-works projects, such as sewer tunnels, shafts are usuallyā¦
Read MoreThe mining industry has been the primary constructor of shafts, because at many locations these are essential for access to ore, for ventilation, and for material transport. Depths of several thousand feet are common. In public-works projects, such as sewer tunnels, shafts are usuallyā¦
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miningVertical openings: shafts and raisesThe principal means of access to an underground ore body is a vertical opening called a shaft. The shaft is excavated, or sunk, from the surface downward to a depth somewhat below the deepest planned mining horizon. At regular intervals along theā¦
Read MoreThe principal means of access to an underground ore body is a vertical opening called a shaft. The shaft is excavated, or sunk, from the surface downward to a depth somewhat below the deepest planned mining horizon. At regular intervals along theā¦
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coal miningShaftsā¦from surface to underground, or shaft, mining. Early shaft mines were little more than wells widened as much as miners dared in the face of danger of collapse. Shafts were sunk on high ground, with aditsānear-horizontal tunnelsāfor drainage driven into the side of the hill. In England some shallow mineā¦
Read Moreā¦from surface to underground, or shaft, mining. Early shaft mines were little more than wells widened as much as miners dared in the face of danger of collapse. Shafts were sunk on high ground, with aditsānear-horizontal tunnelsāfor drainage driven into the side of the hill. In England some shallow mineā¦
Read More- coal miningAccess
ā¦of portal: drift, slope, and shaft. Where a coal seam outcrops to the surface, it is common to drive horizontal entries, called drifts, into the coal seam from the outcrop. Where the coal seam does not outcrop but is not far below the surface, it is accessed by driving slopingā¦
Read Moreā¦of portal: drift, slope, and shaft. Where a coal seam outcrops to the surface, it is common to drive horizontal entries, called drifts, into the coal seam from the outcrop. Where the coal seam does not outcrop but is not far below the surface, it is accessed by driving slopingā¦
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