Excavating, and in Apparatus therefor.
Year: 1886

page_text: Excavating, and in Apparatus therefor.
I CHARLES SOOYSMITH of N° 2, Nassau Street in the City County and State of
New York United States of America, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement
This Invention relates to improvements in apparatus for tunnelling in quicksand
or mud which apparatus is intended to solidify by freezing sufficient of the material
to allow the tunnelling operations to be carried on without interruption. Before
my Invention the idea had already been suggested of solidifying quicksand and
the like by freezing for the purpose of sinking shafts tunnelling etc; but I find
that for constructing a tunnel of a greater length than the freezing pipes it
becomes necessary from time to time to advance these pipes or insert new ones in
order to be able to progress with the work of excavating.
I
: My Invention consists principally in providing the freezing pipes with con-
trivances by which they can become thawing pipes and with other mechanisin
hereinafter described which will permit their ready advancement through the
ground.
°
Reference is to be had to the accompanying drawings forming part of this
Specification wherein Figure 1 represents a sectional view of part of a tunne!
showing my apparatus in position. Figure 2 is a similar section, showing the parts
in a different position. Figure 3 is a cross section on the line cc Figure 1.
In the drawings the letter A represents a part of a tunnel; and B B are the
freezing pipes which are inserted in the soil C for the purpose of solidifying it so
that the tunnel may be advanced by working in the frozen material. The
lines a show the extent to which the soft soil is supposed to be frozen or solidified
by the freezing fluid which at the proper time is caused to traverse the pipes' B B:
It will be readily understood that if I had only these freezing pipes and means
to utilize then as such they could not be pushed forward in the soil unless the
head of the tunnel or excavation was advanced to the limit of the frozen portion
of the ground in which case the soft character of the soil at or very near to the
heading would be liable to fall into the excavation and seriously check the progress
of the work. My intention is, for the purpose of obviating this difficulty and

page_text: permitting the pipes B B to be advanced through the frozen portion of the
ground, to provide the pipes with means for thawing their immediate surroundings
so that there would be produced around each of the pipes B B.a zone of
softened or thawed material through which such pipes could be pushed forward
while the bulk of the soil would remain frozen. The tubes b b which are shown
in the upper pipe B of Figure 1 indicate the conduits for the freezing fluid which
when passed through the pipes B B will cause the soil to freeze up to the line a.
The tubes dd in the upper pipe B Figure 1 indicate the conduits for letting a
thawing fluid into the pipe B and when this thawing fluid is allowed to circulate
each pipe B will be surrounded by a zone 'e of thawed ground through which the
said pipes can now be pushed forward as far as desired whereupon the thawing
process is stopped and freezing is resorted to, to permit the tunnel or excavation
to be carried further on. It will be perceived from an inspection of the drawings
that the thaw line e around each pipe B does not extend fully to the head of the
tunnel or excavation and that therefore there is no danger of the heading falling
in because softened by the thawing. Encircling each pipe B for some distance
from the heading into the frozen mass is, or may be, a sleeve D. Whenever the
thawing pipes d are made use of to produce the zones ee of softened matter the
pipes B B are pushed forward the desired distance by hydraulic or other pressure.
The vehicle of heat not having circulated near the heading the frozen mass remains
as such at the heading and each pipe B when pushed forward moves through
the sleeve D that surrounds it and that prevents the thawed material about the
pipe B from coming into the excavated space. After the material about a pipe B
has been again frozen some distance beyond the sleeve the ground immediately,
around each sleeve is slightly thawed by using a shorter pipe f as a conduit for the
heating fluid and pressure being applied to the sleeve this too can now be pushed
forward. The sleeves D D may be dispensed with where the soil is of a muddy
nature, because in that case the muddy material, owing to its semi solid con-
sistency will not flow backwards along the pipes B B even if the ground
immediately around them is thawed to permit their advancement. When the
pipes B B with or without the sleeves D D have been moved forward the excavation
is also carried forward and the lining E built before the frozen mass near the
unwalled excavated space can thaw. With a small tunnel one pipe will suffice.
I may if found desirable provide a means of drilling through the pipe B without
changing materially the arrangement described, or I may arrange a jet of water
to play against the material at the end of the pipe B whilst the latter is being
pushed forward. It will be seen from the foregoing description that where the
sleeves D D are used there are three operations of thawing and freezing namely:
(1st) The ground is frozen to the lines a. This is done by using the pipes bas
conduits for the freezing fluid. (2nd) The ground is thawed around each pipe B
up to the limits e and the pipes BB are then pushed forward. (3rd) The ground
is thawed around each sleeve D up to the limit g and the sleeves D D are then
pushed forward, afterwards the ground is again frozen around the pipe and sleeve.
The constructing of each pipe B to permit the three operations just mentioned
is preferably as follows;-Each pipe has a series of transverse diaphragms, four
being shown at hij and k. The front three diaphragms ij and k have a number
of small holes in them, the freezing fluid supplied to b terminates in the space
between the diaphragm j and k and has at its back end a suitable connection with
the source of supply. The freezing fluid escapes when desired through the shorter
tube b. Suitable valves or cocks should be in said tubes to allow each to be opened
or closed when desired. For the second operation I supply thawing mixture
through the longer tube d which reaches nearly to the end of the pipe B the fluid
escaping through the short tube d. For the third operation, that is, thawing
around and in advance of the sleeve I supply the thawing fluid through the tube f
and take it out by the shorter tube d. But this arrangement of tubes may be
varied, and the several fluids may be supplied to the pipe B by the shorter
tubes and taken out by the longer tubes, if desired. If preferred, the diaphragms 2.
L'

page_text: jand k may be inade tight or extra pipes used to permit circulation in the main
pipe B.
I have also shown a means of moving the pipes B and their sleeves D by
hydraulic pressure. Each sleeve D connects by arms or rods m m with a cylinder F
which partly embraces a stationary block G that is braced against or held firm by
a stationary frame work H. Each pipe B terminates at its outer end, that is, the
back end, by a cylinder I which embraces the cylinder F. There is a closed
diaphragm n at the end of this cylinder I at some distance from the end of the
cylinder F. Thus there are two cylindrical spaces formed, the one o within the
cylinder F between its end and the end of the block G, the other p within
the cylinder I between its end n and the end of the cylinder F. Whenever the
pipe B has to be pushed into the soil, suitable fluid is forced into the space p
through the aperture q the cylinder F being held stationary, meanwhile, by stop-
ping the passager in the block G. Whenever the sleeve D is to be moved the
Huid is forced into the spaces o through the passage r. The passage shown in the
drawing between the cylinders ọ and p is plugged up when the machine is in
operation.
I desire it to be understood that when I mention a "tunnel" in this specification
I mean any excavation in a horizontal, vertical, or other direction of any kind
whatsoever to which the Invention described is applicable.
Having now particularly described and ascertained the nature of the said
Invention and in what manner the same is to be performed I declare that what
I claim is;
1. The freezing pipes B provided with conduits for freezing fluids and for
thawing fluids, substantially as and for the purpose described.
2. The pipe B provided with conduits for freezing fluids and for thawing fluids,
combined with the sleeve D substantially as described.
3. The pipe B having transverse partitions combined with the conduits b d and f
and with the sleeve D substantially as described.
4. The combination of the pipe B and sleeve D with the block G cylinders F
and I and arms m substantially as and for the purpose herein shown and described.
5. In the art of tunnelling through quicksand or soft soil, the pipe B provided
with inner conduits all arranged so that a vehicle of cold and a vehicle of heat can
be circulated successively through desired portions of said pipe for alternately
freezing and thawing around said pipe as specified.
6. The combination of a pipe for freezing the soil to be tunnelled with a pipe
for thawing the soil around said freezing pipe substantially as herein shown and
described.
7. The process of preparing soft soil for tunnelling which consists in first freezing
the soil around one or more pipes, in then thawing part of the frozen soil around
each of the pipes and in then advancing said pipes through the thawed portion
and freezing again substantially as described.
8. The process of preparing soft soil for tunnelling which consists in first freezing
the ground around one or more pipes and sleeves, in then thawing around each
pipe, in then advanced each pipe through the thawed ground in then thawing
around each sleeve and advancing each sleeve through the thawed portion and in
finally freezing the thawed portion as specified.