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Showing posts with the label explain shaft and portal in tunnel

SHAFTS AND PORTAL

GET RID OF METHODOLOGY AND MOVE TOWARDS THE APPLICATION OF SHAFTS AND PORTALS IN TUNNEL Introduction about Shaft and Portal in Tunneling Shafts are vertical tunnels reaching from ground surface down to tunnel roof . They afford many advantages and used in constructing tunnel. When the position and course of tunnel are correctly aligned and accordingly set out on the surface shafts are sunk at suitable points on this tunnel line to aid tunneling advantages  Location of Shaft and Portal Shaft   are verticals tunnels reaching from ground surface down to tunnel roof .They afford manifold advantages and uses in constructing tunnels Shaft are sunk at suitable points on tunnel line to aid tunneling operations Rectangular shape is preferred for temporary shaft and circular shape  is preferred for vertical shaft  Ideal site selection  for shaft is valley Advantages of Shaft and portal They greatly expedite the work by adding two faces per shaft for driving They afford outlets for excavated