Search results
Results from the WOW.Com Content Network
Shaft mining or shaft sinking is the action of excavating a mine shaft from the top down, where there is initially no access to the bottom. [1] Shallow shafts , typically sunk for civil engineering projects, differ greatly in execution method from deep shafts, typically sunk for mining projects.
Tunnels in the complex dug by Baldassare Forestiere The accidental discovery of one of Harrison Dyar's tunnels in 1924. Hobby tunneling is tunnel construction as a pastime. [1] [2] Usually, hobby tunnelers dig their tunnels by hand, using little equipment, and some can spend years or even decades to achieve any degree of completion. [2]
Sinking a dry shaft means that any water that flows into the excavation is pumped out to leave no significant standing or flowing water in the base of the shaft. When wet sinking a shaft the shaft is allowed to flood and the muck is excavated out of the base of the shaft underwater using a grab on the end of a crane or similar excavation method.
A bell pit was a type of coal mine in which coal found close to the surface was extracted by sinking a shaft and removing coal from around it until the roof became unstable. It was then abandoned and left to subside. [5] Bind. A term used in various areas to refer to shale, mudstone, clay or sandstone overlying the seam. Bituminous coal
Shaft sinking was the most dangerous and most difficult form of mining in ancient Rome. Due to its high cost, it was only used to collect the most valuable metals in Roman society. This technique involved digging tunnels underground, allowing workers to extract the ore.
Tunnel Construction. Tunnels are dug in types of materials varying from soft clay to hard rock. The method of tunnel construction depends on such factors as the ground conditions, the ground water conditions, the length and diameter of the tunnel drive, the depth of the tunnel, the logistics of supporting the tunnel excavation, the final use and shape of the tunnel and appropriate risk management.
The $23 million project started on April 8, 1933. Tunnel crews dug from four directions: the two main portals and two shafts. [1]On July 1, 1934, one of the tunnel crews narrowly escaped the tunnel as ground water burst in and began filling the tunnel and shafts at a rate of nearly 8,000 US gallons per minute (0.50 m3/s).
Part of a former silver mine, the adit was used for removing water from the mine. It still carries water from old galleries to the nearest river. A part of it is open for tourists, who go 20 metres (66 ft) down the steps in one shaft, have a ride in a boat, and go up the stairs in another shaft. Blue Hawk Mine near Kelowna, British Columbia ...