Improvements relating to Tunnelling and to Apparatus therefor.
Year: 1889

page_text: Date of Application, 13th May, 1889-Accepted, 10th Aug., 1889
COMPTAIN SIMULFIOA
Improvements relating to Tunnelling and to Apparatus therefor.
I, LUTHER BEECHER of 437 Jefferson Avenue, Detroit, in the County of Wayne
and State of Michigan, United States of America, Capitalist, 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 :-
My invention relates to the construction of sub-aqueous tunnels and consists in the
method of tunnelling and in the mechanical means and appliances by which such
method is carried out and further in the peculiar construction of the tunnel casing, all
as hereinafter described.
My method of tunnelling contemplates the construction of sub-aqueous tunnels
without the necessity of removing the earth, and whereby the earth becomes an
element of strength and protection to the tunnel.
To this end, the way for the tunnel casing is forced by means of a wedge-shaped
bulk head, or what I call a tunnelling ram, which slides with a water-tight joint on
the construction end of the tunnel casing, and which is driven forward with sufficient
power to displace the earth in front of it upwards, so as to cover the top of the tunnel,
the latter passing in suitable proximity to and below the bottom of a river or body of
water to permit this displacement of the earth. To assist the operation of the
tunnelling ram, the earth in front of it if necessary is loosened up to the required
depth and stones, rocks or other obstacles are removed or broken up by the use of
explosives. This work is accomplished with the help of a vessel provided with the
Plastic packing is
required outfit and operating in advance of the tunnelling ram.
used to form a water-tight joint between the casing and the sliding end of the
tunnelling ram, and this packing remains permanently on the outside of the casing.
Devices are provided for steering the tunnelling ram, and other provisions are made
to meet contingencies, necessitating the temporary use of other modes of tunnelling.
In the accompanying drawings.
Figure 1 is a vertical cross-section of a tunnel in process of construction in
accordance with my invention.
Figure 2 is an enlarged vertical central, longitudinal section of the construction end
thereof.
Figure 3 is a cross-section of the tunnel as completed.
Figure 4 is a cross-section of the tunnelling rami on line X, X of Figure 2.
Figure 5 is a plan thereof.
Figure 6 is an enlarged perspective view of a plate of the casing of which I intend
to construct my tunnel.
Figure 7 is a cross section on line Y Y in Figure 2, and
Figure 8 is a detail cross-section through two plates showing the construction of
the points.
A are segmental rectangular plates of cast-iron smooth on the outside and provided
on the edges with inwardly projecting flanges a, for bolting the plates end wise and
side-wise together to form a tunnel of the desired cross-section; similar flanges or
ribs & may be provided centrally to strengthen the plates.
To form water-tight joints, I provide all the plates alike upon their ends and sides
with tenons c and grooves d whereby in joining the plates together the tenons on one
plate will engage into the corresponding grooves in the adjoining plate. The plates
are preferable bolted together to break joints, and soft metal gaskets B are inserted
between the joints. For the purpose I use preferably lead plates, through which the
bolt holes are formed by means of a pointed tool, which gradually enlarges the bolt-
hole to force the lead into the joint between the flanges around the bolt-hole.
In addition to this metal packing, the joints may be coated with paint, asphalt,
coal-tar or any other compound usually used in constructions of this kind.

page_text: These metallic plates [ make of a size and shape convenient for handling and to be
readily transported through the interior of the tunnel as its construction advances.
I deem cast-iron to be the most suitable material for constructing the plates, but I
do not intend to limit myself to this material alone, or to its exclusive use for, if
occasion should require, or I should deem it expedient, I intend to provide the casing
with a suitable lining on the inside such as masonry, terra cotta, cement or other
heavy material, or fill the openings formed between the flanges of each plate with
solid cast iron blocks, firmly wedged or keyed in as may be required to give the
necessary strength, weight and stability to the structure, and to overcome the
buoyancy thereof, and the pressure of water upon it.
While building this tunnel on land, I proceed as usual by excavating the earth and
in lengthening the tunnel I add the sections on top first, to form a protecting hood,
and gradually add plates to the sides and bottom, keeping the top plates always
advanced.
In building this tunnel under the bed of a river, lake etc. I proceed after the
method described above, by building on the open end of the tunnel casing the hollow
sliding bulk head or tunnelling ram C which is wedge-shaped at its forward end and
slightly tapering at its rear end and sufficiently larger than the tunnel to loosely
embrace it and form an annular space for packing. This tunnelling ram I construct
in a similar manner of sectional plates as described for the casing of the tunnel except
that the tapering end is smooth on the inside. The front edge or wedge shaped
portion I construct preferably in a solid manner, and with a movable point or nose D
which is connected by a strong knuckle joint which turns on the steel shaft E and is
solidly backed in circular bearings on the head.
This movable nose is adapted to be raised or lowered by providing it with hydraulic
chambers e and for with suitable mechanical devices, such as the lever g adapted to
be worked from the inside and having a sufficient amplitude of motion to raise or
lower the point within the easy grades permissible for tunnels.
The whole point or wedge-shaped portion of the tunnelling ram is solidly constructed
of cast iron or steel to resist the hydraulic pressure exerted against it by a series of
hydraulic cylinders F, placed against its bulk-head and disposed near the outside of
the shell and forming a strengthening part thereto and being integral there with or
forming an inner lining therefor.
The pistons G of these hydraulic cylinders which correspond in number with the
number of plates composing the circle operate in the longitudinal direction of the ram
and are in a line corresponding with the casing of the tunnel whereby in operation
the force of the piston may be exerted end wise and in a line with the casing or walls
of the tunnel each piston being suitably blocked or abutted against the contiguous
portion of the casing or walls of the tunnel to exert a direct thrust upon it when the
hydraulic pressure is exerted upon the piston.
The hydraulic pressure can be applied for two purposes, first for forcing the
tunnelling ram the necessary distance ahead to lengthen the tunnel casing and
secondly, to force each individual plate into position when the tunnel is lengthened
out, as it requires some power to compress the packing sufficiently to make the tongue
and groove joints with the soft metal packing between as described.
By constructing the pistons with the screw extension G¹ as shown, they may be
readily abutted against the plates.
When hydraulic pressure is applied to all the pistons to drive the tunnelling ram
the necessary distance forward, all the plates may be firmly compacted endwiso and
side also on account of the pressure on the casing and of the slightly tapering shape
of the tunnelling ram, the bolts are uniformly tightened on all the joints wherever
necessary.
•
To form a tight joint between the overlapping ends of the tunnelling ram and the
casing of the tunnel I compact into the annular space a plastic packing or cement
preferably composed of asphalt, coal-tar or other bitumen mixed with cement and
with a fibrous material such as tow or old rope and this packing is of an adhesive
nature and hardens and sets after a while,

page_text: As the tunnelling ram advances by being forced forward the packing is compressed
on to the casing by the tapering rear end and it is thereby forced into all the joints of
the casing and forms an outward protective layer around the tunnel. New packing
is added whenever the casing is lengthened out.
As my method of tunnelling contemplates the building of a tunnel just below the
bottom of a body of water, as nearly as is possible without making too many or abrupt
changes in the grade of the tunnel I raise or lower the hinged nose of the tunnelling
ram in a proper degree to steer the tunnelling ram up or down as required. The
power of the hydraulic pistons may also be applied to effect the steering of the
tunnelling ram up or down or to one side or the other by applying the pressure
unequally to the bulk-head.
To effect the lateral steering of the tunnelling ram, by mechanical means I provide
the latter near the forward end with the hinged wings H which fold into suitable
recesses provided upon the side of the tunnelling ram and are provided with hydraulic
pressure chambers or other mechanical devices to open them laterally when required
to crowd the tunnelling ram to one side or the other.
The advantage obtained by keeping always in the same proximity below the bed of
the river or other body of water or nearly so is that I thereby make it possible for my
tunnelling ram to displace the ground in front thereof upwardly when forced ahead
by suitable hydraulic pressure.
At the same time the ground is firmly compacted all
around and forms a protective layer all around the top of the tunnel which is
composed of the solid soil raised up from the bottom of the tunnel and which may he
afterwards further compacted from the outside in any suitable manner.
The light
material such as silt or other debris usually found in the bottom of rivers etc.; is
raised up from the bottom to be carried away by the water.
My method of tunnelling in close proximity to the bottom of the water permits me
to simultaneously carry on the operation of loosening the soil in advance of the
tunnelling ram. This I carry out by anchoring a suitable scow, boat or raft I in
advance of the tunnelling ram, which is provided with suitable mechanical devices to
loosen, work or puddle the ground in advance of the ram from above, such as by
means of suitable tools lowered into the ground to the required depth.
By this operation I also discover any obstacles to the progress of the ram and
remove the same in any suitable manner such as by means of explosives or otherwise.
This operation of loosening the ground in advance of the tunnelling ram, may be
accomplished if desired by the use of explosives as in the manner of deepening
channel beds in rock-bottom.
By loosening and working the ground in this manner not only boulders and other
obstacles are discovered but the work of the tunnelling ram becomes at once possible
under all conditions of soil and as clayey soil is thereby transformed into a plastio
cement, a new element of strength and durability is added to the structure as the clay,
after becoming compacted again forms a waterproof covering around the tunnel.
For such contingencies as are found in subaqueous constructions, where liability
exists from being undermined, as where channels are changing I introduce a new
element of protection which consists of driving piles alongside the casing of the
tunnel, slightly inclined so as to pin or hold the tunnel to the bed and placed in pairs
opposite to each other to permit of their being yoked together over the top of the
tunnel by suitable cross-pieces or iron yokes. This piling may be carried out in
advance of the tunnel to guide the tunnelling ram in its operation, in which case the
side wings for steering are not required.
In the practical construction of my tunnel I start the sub-aqueous portion of the
tunnel preferably from the bottom of a vertical shaft of suitable size to afford a
convenient entrance into the tunnel for lowering the material and serving also as an
air-shaft. On the bottom of this shaft I provide a cistern or well suitable to receive
the ordinary leakage or drainage from the tunnel, and from which it may be pumped
out. This I cover over with a strong platform in line with the bottom of the intended
tunnel and upon this I begin to construct my tunnelling ram projecting out through

page_text: t
the sides of the shaft. If necessary, a suitable copper is constructed outside around
the tunnelling ram to protect the shaft against the ingress of water.
After the tunnelling ram is completed, I begin to construct a section of my tunnel
casing inside of the rear end of the tunnelling ram and after securing the packing
in place, the rear end of the casing is abutted against the rear end of the shaft and
the front end of each plate of the casing I abut against its corresponding hydraulic
piston. After having made all the necessary provisions for allowing the tunnelling.
ram to be pushed ahead in the manner intended this operation is then proceeded
with by forcing the water by means of a large force pump, preferably placed in
proximity to the shaft into the hydraulic cylinders until the tunnelling ram has been
advanced the necessary distance required for securing new plates to the tunnel casing
after the pistons are withdrawn into the hydraulic cylinders. By alternatingly
driving the tunnelling ram ahead and lengthening the casing, adding to it a new
set of plates all around with the necessary packing to maintain a water-tight joint
the construction of the tunnel is carried out substantially after the method described.
It is obvious that I intend to avail myself of all the facilities and modern appliances
of which engineers in carrying out such constructions generally avail themselves
such as laying a temporary track inside the tunnel for running a truck or trucks
thereon to transport the material the construction of suitable drain or pipe systems to
afford drainage and to convey the hydraulic pressure into the hydraulic cylinders and
other suitable provisions for lighting, heating or whatever may be required for the
comfort of the workmen and for expediting the work.
There may be sections of work where my method of tunnelling is not available
or would be at a disadvantage compared with other known methods but it will be
an easy matter to make suitable provisions in the construction of the tunnelling
ram to permit of using excavating machinery applied through suitable openings
'provided for in the bulkhead. As the nature of the work and the difficulties to
be encountered can all be known in advance through a careful survey, which
ought necessarily to precede the commencement of the work no contingencies are
liable to arise for which no adequate provisions can be made or which engineering
skill is not able to meet, and while quick-sand is generally accounted to be the
*most troublesome factor in tunnel construction no difficulty at all arises from this
source in my method of tunnelling.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
First In sub-aqueous tunnelling, a tunnelling ram provided with a wedge-shaped
obulk-head adapted to displace the ground upwardly and forming a water-tight com-
partment slidingly operating on the head of the tunnel casing, substantially as
described.
Second The combination with the tunnelling ram provided with the wedge-
shaped bulk-head and forming a water-tight compartment slidingly secured on the
head of the tunnel casing of a series of hydraulic jacks grouped around the inner
wall of said ram against the bulk-head thereof, and with their pistons adapted to
operate in line with the casing of the tunnel, substantially as described.
Third-In sul-aqueous tunnelling, a tunnelling ram provided with a solid bulk-head
constructed in the form of a wedge adapted to displace the ground upwardly when
pushed ahead and with a movable point or nose for steering it, said tunnelling
ram being adapted to slidingly operate on the head of the tunnel casing and forming
a water-tight compartment for extending the tunnel casing within said tunnelling
ram, substantially as described.
Fourth In sub-aqueous tunnelling, a tunnelling ram provided at its front end with
⚫a solid bulk-head having its front face rearwardly inclined from the bottom to the
top, and having a hinged point or nose, and laterally extensible wings, substantially
as described.

page_text: Fifth The combination with the casing and tunnelling ram slidingly secured
thereon, of the plastic packing applied between the tunnelling ram and casing to form
a water-tight joint, substantially as described.
Sixth-In sub-aqueous tunnelling, the combination with the casing of a tunnelling
ram provided with a tapering rear end and a plastic packing applied to the annular
space between said tapering rear end and the casing of the tunnel, said tunnelling
ram forming a water-tight compartment on the head of the casing and provided with
means for advancing it, to permit of extending the casing within the tunnelling ram,
substantially as described.
Seventh-In sub-aqueous tunnelling, the combination with a casing constructed of
rectangular segmental cast-iron plates smooth on the outside and interiorly flanged on
their edges for securing said plates together by bolts, of the tunnelling ram provided
with a tapering rear end smooth on the outside and slidingly engaging with the end of
the tunnel casing by means of a plastic packing adapted to form a permanent covering
on the outside of the tunnel casing, substantially as described.
Eighth In sub-aqueous tunnelling the combination of a tunnel casing consisting
of rectangular segmental iron plates adapted to be interiorly bolted together with
intervening gaskets by means of interior flanges provided with corresponding tongues
and grooves, a tunnelling ram provided with a solid bulk-head wedge-shaped at its
outer face and with a tapering rear end sliding on the head of the casing with a
water-tight joint formed of a plastic material adapted to form a permanent covering
on the outside of the tunnel casing a series of hydraulic rams grouped around the
inner walls of said tunnelling ram and adapted to operate with their pistons against
the inner ends of the plates of the casing to force the same in place and advance the
tunnelling ram substantially as described.
Ninth A tunnel casing composed of rectangular segmental cast-iron plates, smooth
upon their outer faces and provided alike with corresponding grooves and tongues
upon their edges to form a tongue and groove joint for securing the plates together,
and of interior flanges on the outer edges of said plates by means of which the
plates are bolted together to break joints, with an intervening gasket of soft metal
plate between said flanges, substantially as described.
Tenth The herein described method of constructing sub-aqueous tunnels consisting
in extending the main casing step by step within a tunnelling ram adapted to be
advanced thereon and using a plastic packing between the main casing and tunnelling
ram, substantially as described.
Eleventh The herein improvement in the art of constructing sub-aqueous tunnels
consisting in extending the casing step by step with a tunnelling ram slidingly
secured thereon and provided with a wedge-shaped bulk head whereby the earth
in front of said tunnelling ram may be displaced upwardly by forcing said ram
forward in combination with the process of preparing or loosening the ground. in
advance of the tunnelling ram, substantially as described.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.