Page 39 - Trenchless Technology Piping Installation and Inspection
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14 Cha pte r O n e
FIGURE 1.10 (a) Worker entry EPBM. (b) Worker entry slurry machine.
(Source: Pipe Jacking Association.)
sections are transported inside the tunnel, and the annular space
between the liner and the pipe is normally grouted. Due to separate
phases of liner installation and pipe installation, the utility tunneling is
called a two-step or two-phase operation, while conventional pipe
jacking is called a one-step or one-phase operation. In general, person-
nel are required inside the pipe to perform the tunneling and soil-
removal operations. The main components of the utility-tunneling
method are the same as conventional pipe jacking, except in the utility
