6.3
Materials (03 43xxx)
03 43001
muck pile
03 43002
soil conditioner
additive (01) injected into a cutter head (03 46070) to facilitate handling of excavated material by lubrication or coagulation (BS 6068-1.4)
03 43003
rebound
portion of sprayed concrete (09 33035) that bounces from the surface to which it is applied because of the velocity (BS EN ISO 772) at the time of impact
03 43004
silica fume
by-product of producing silicon metal and ferro-silicon alloys; it consists of mainly spherical particles of amorphous silicon dioxide and is highly pozzolanic
03 43005
tailskin grease
6.4
Activities (03 44xxx)
03 44001
box the face
box up
cover the whole or part of a tunnel face (03 42019) to provide support
03 44002
dental treatment
tunnel lining (03 42005) of small areas of the periphery at faults (01) or large fissures (BS EN 12670) using concrete (01)
03 44003
clay pocketing
method of tunnelling through loose ground (01) by digging out small pockets around the periphery of the excavation (01), backfilling (01) them with clay (BS EN 12670) and embedding a tunnel shield (03 46032) in the clay (BS EN 12670) to make a watertight seal
03 44004
shield roll
rotation of a tunnel shield (03 46032) about its axis during a drive
03 44005
blanket
deposit an impermeable layer on a tunnel face (03 42019) to limit compressed air (BS EN 12110) losses
03 44006
pull
03 44007
back grouting
process of injecting grout (01) around a tunnel lining (03 42005) after initial injection of grout (01)
03 44008
blind boring
process of drilling a hole without carrying out an exploratory probe (03 44011)
03 44009
cut and cover
construction of a tunnel (01) with an open excavation (01) that is subsequently covered with soil (01)
03 44010
new Austrian tunnelling method
NOTE Rock bolts (03 22022) and shotcrete (09 33034) are commonly used.
03 44011
probe
drill a small diameter hole outside or in front of a tunnel (01) for ground investigation (03 24002)
03 44012
forepole
support loose ground (01) by driving poling boards (03 26029) immediately ahead of the tunnel face (03 42019)
03 44013
muck out
remove excavated material from a tunnel (01)
03 44014
raise boring
method of excavating (01) a shaft (01) by boring upwards
03 44015
scale down
remove from the arch (01) of a tunnel (01) rock (03 23027) pieces loosened but not dislodged by a round (BS 5607), or that become loose later
03 44016
shove
incremental forward movement of a tunnel shield (03 46032), tunnel boring machine (03 46029) or pipe (01)
NOTE Usually by means of hydraulic rams (05 12121).
03 44017
directional drilling
technique for installing a pipe (01) or duct (01) on a slightly curved line using a machine with a guided steerable drilling head to form a hole into which the pipe (01) or duct (01) is inserted
03 44018
impact moling
technique for installing a pipe (01) or duct (01) using a percussive soil (01) displacement device to form a hole into which a pipe (01) or duct (01) is pulled or pushed
03 44019
wet process
process of spraying concrete (01) where the hydraulic binder (01), aggregate (01) and water are mixed before being supplied to a nozzle
03 44020
dry process
process of spraying concrete (01) where a dry hydraulic binder (01) and aggregate (01) mix is supplied to a nozzle and water added at the nozzle
03 44021
break out
03 44022
break up
construct an opening in the roof of a tunnel (01) for a junction with a shaft (01) or an enlarged tunnel (01)
03 44023
caulk
form a pre-formed joint (01) between tunnel segments (03 42011) to form a watertight seal
03 44024
lock in
03 44025
lock out
03 44026
decant
undergo rapid decompression in a personnel lock (BS EN 12110) and then move to a decant lock (03 46095) nearby to be compressed to an appropriate pressure and then decompressed in accordance with normal practice
NOTE This procedure is now exceptional in UK.
03 44027
oxygen decompression
use of oxygen for breathing during decompression
03 44028
chemical injection
inject chemicals into the ground (01) to modify fill (01) and/or soil (01) behaviour by physiochemical processes or by cementing the fill (01) and soil (01) together
03 44029
collar
ensure the correct location of a larger diameter hole by first drilling a smaller one for a short distance, then enlarging the hole to the required size (01) and finally inserting the full size (01) rock drill (12 26040) rod (01)
cf. collar (03 12037)
03 44030
spile
stabilize a tunnel face (03 42019) by insertion of poles, bars (01) or holes filled with grout (01) forward of the tunnel face (03 42019)
6.5
Processes (03 45xxx)
03 45001
piping
excess water pressure from within a caisson (01) causing material at the base, outside, to become unstable; the material partly removed by the flowing water is replaced by material from within the caisson (01) thus forming a hollow similar to a pipe (01)
cf. piping (03 25003)
03 45002
squat
downward deflection (03 15001) from true of atunnel crown (03 42021)