Search results
Results from the WOW.Com Content Network
Directional boring, also referred to as horizontal directional drilling (HDD), is a minimal impact trenchless method of installing underground utilities such as pipe, conduit, or cables in a relatively shallow arc or radius along a prescribed underground path using a surface-launched drilling rig. Directional boring offers significant ...
The purpose of the drill is to create a tunnel under surface obstructions. First, the operator surveys the area and the obstacle (road, sidewalk, driveway). Utility locators must supervise any underground work, and the path most clear of utilities is chosen to send the tool through. The first hole is dug on one side of the obstacle.
A tunnel boring machine (TBM), also known as a "mole" or a "worm", is a machine used to excavate tunnels. Tunnels are excavated through hard rock, wet or dry soil, or sand, each of which requires specialized technology. Tunnel boring machines are an alternative to drilling and blasting (D&B) methods and "hand mining".
Both incidents add to a series of safety episodes that have taken place since the Boring Company began work to expand its existing tunnel system—currently a 2.4-mile, one-way underground conduit ...
A schematic overview of the machinery used irony a raised boring. A raise borer is a machine used in underground mining, to excavate a circular hole between two levels of a mine without the use of explosives. The raise borer is set up on the upper level of the two levels to be connected, on an evenly laid platform (typically a concrete pad).
Freighter Fairpartner carrying the disassembled tunnel boring machine into the Port of Seattle in April 2013. Bertha was designed and manufactured by Hitachi Zosen Sakai Works of Osaka, Japan, and was the world's largest earth pressure balance tunnel boring machine, [14] at a cutterhead diameter of 57.5 feet (17.5 m) across.
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.
A tunnel boring machine (TBM) consists of a shield (a large metal cylinder) and trailing support mechanisms. A rotating cutting wheel is located at the front end of the shield. Behind the cutting wheel there is a chamber where the excavated soil is either mixed with slurry (so-called slurry TBM) or left as-is (earth pressure balance or EPB ...