Improvements in or appertaining to the Construction of Submarine or Submerged Tunnels.
Year: 1890

page_text: Date of Application, 11th Jan., 1890
Complete Specification Left, 9th Aug., 1890-Accepted, 13th Sept., 1890
PROVISIONAL SPECIFICATION.
Improvements in or appertaining to the Construction of Submarine
or Submerged Tunnels.
I, THOMAS THOMSON of Blennerville, Tralee, in the County of Kerry, Ireland,
Civil Engineer, do hereby declare the nature of this invention to be as follows:-
This invention has for its object a new form of tunnel and method of forming the
same, whereby the tunnel can be placed as near as practicable to the level of the surface
of the bottom of the river or arm of the sea crossed by the channel.
By my invention, I form two rows of sheet piling or its equivalent and then excavate
between these two and sink the tunnel into the excavation in sections, and fill up with
concrete, masonry or the like in such manner as to leave the top of the concrete
preferably level with the bed of the river on each side of the line of piles. The bed of
the river or arm of the sea may be protected if necessary by stone, concrete or the
like, but this, as a rule, is not necessary.
The mode I prefer for carrying out my invention is as follows:-
I divide the channel or river proposed to be tunnelled into a certain number of sections,
from 200 to 300 feet long. In one of these sections I drive two rows of sheet piling
at a distance apart sufficient to contain a tunnel tube and concrete at the sides of same
as hereinafter described, said piling being driven below the bottom of the intended
tunnel and finished flush with the bed of the river or nearly so. I also drive sheet piling
of the same description across the ends of the section. On the inner face of this piling
and near the top thereof I fix a timber or iron waling by means of divers. Should the
excavation be too deep for these piles to support themselves during the excavation, I
then drive tie piles at a sufficient distance back from this piling and attach the waling
of the sheet piles to these tie piles by means of tie chains or rods of sufficient strength.
I leave these tie piles of sufficient length that their heads may be above water, and
I pass the tie chain round a casting fixed on the pile at the level of the river bed and
fasten it at the head of the pile by a tightening screw, I then excavate, by means of
dredgers, the earth contained in the rectangular space bounded by the sheet piles
down to a sufficient level to contain the tube and concrete hereinafter described. On
the bottom of this excavation 1 then place a layer of concrete.
I then have an iron tube prepared of the sectional dimensions of the proposed tunnel
and of a length equal to the section piled; said tube being clòsed at the ends with
temporary diaphragms of metal or wood and also having a middle diaphragm for
facility in sinking. I have two chimneys or funnels built out of this tube to a height
sufficient to stand above the surface of the water when the tube is sunk, I close these
funnels at the top and provide them with valves for allowing air to escape from the
tubes, I also place two valves for admitting water, one in each division of the tube, and
I lead lever connections from said valves to the tops of the funnels, the tube may be
either constructed with sufficient bracing of angle iron to prevent change of foran or it
may be strutted internally with timber temporarily.
The tube, being constructed on shore and launched, is moored over the rectangular
space prepared for it, and sunk, the space remaining between the tube and the piling
I then fill with concrete.
I then pile another section of the tunnel in a similar manner to the aforementioned,
and excavate it, I then remove the sheet piling between the two lengths and deposit
the second length of tube as close as possible to the first length, so proceeding till all
the lengths have been executed. I then remove the water from the tubes, the concrete
making them sufficiently water-tight to do so, when the diaphragms are removed, but
to prevent any permanent leakage, I connect the ends of the tubes as follows:-
At the end of the tube, I enlarge the internal diameter, and at a short distance from

page_text: the end of this enlargement, I place an inner angle iron ring. When the two tubes
are set, these angle irons will come opposite each other, but at a variable distance apart
due to any inaccuracies in setting the tube.
When the tunnel is pumped dry, I measure the exact distance between the angle
irons, prepare a flange plate to fit, and rivet the flanges to the angle irons, the plate
then forms a water tight joint.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in or appertaining to the Construction of Submarine
or Submerged Tunnels.
I, THOMAS THOMSON of Blennerville, Tralee, in the County of Kerry, Ireland,
Civil Engineer, 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 has for its object a new form of tunnel and method of forming the
same, whereby the tunnel can be placed as near as practicable to the level of the surface
of the bottom of the river or arm of the sea crossed by the tunuel.
By my invention, I form two rows of sheet piling or its equivalent and then excavate
between these two and sink the tunnel into the excavation in sections, and fill up with
concrete, masonry or the like in such manner as to leave the top of the concrete
preferably level with the bed of the river on each side of the line of piles. The bed
of the river or arm of the sea may be protected, if necessary, by stone, concrete or
the like, but this, as a rule, is not necessary.
The mode I prefer for carrying out my invention is as follows, reference being had
to the accompanying drawings, in which :-
Figure 1 is a plan showing the arrangement of piling employed in constructing the
tunnel.
Figure 2 is a section on line xx, Figure 1.
Figure 3 is a side view on a reduced scale of one length of the tunnel tube, one
half of it being in section.
Figure 4 is an enlarged detail view of the junction end of a tunnel tube.
Figure 5 is a similar view to Figure 4 showing the completed junction of two tubes.
I divide the channel or river bed which it is proposed to tunnel into a certain number
of sections A A, say, from 200 to 3:10 feet long. In one of these sections I drive two
rows B B of sheet piling, at a distance apart sufficient to contain a tunnel tube and
concrete at the sides of same, as hereinafter described, said piling being driven below
the level of the bottom of the intended tunnel and finished flush with the bed of
the river or nearly so, as seen in Figure 2. I also drive sheet piling B₁, of the same
description, across the ends of the section. On the inner face of this piling and near
the top thereof I fix, by means of divers, a timber or iron waling C. Similar waling C¹
is also applied, if desirable, to the cross piling B'. Should the excavation be too deep,
or the pressure of earth behind the piles too great, for the piles to support themselves
during the excavation, I then drive tie piles D at a sufficient distance in the rear of
this piling, and I attach the waling (of the sheet piles to the tie piles D, by means
of tie chains or rods E of sufficient strength. I leave these tie piles of sufficient
length that their heads may be above water, and I pass each tie chain E (as shown in
Figure 2) round a casting or guide wheel F fixed on the corresponding pile at the
level of the river bed, the chain being fastened at the head of the pile by a tightening
screw G. I then excavate, by means of dredgers, or otherwise, the earth contained
in the rectangular space bounded by the sheet piles B B' down to a sufficient level to
contain the tunnel tube and concrete hereinafter described. On the bottom of this
oxcavation I then place a layer of concrete.

page_text: I then have an iron tube H prepared of the sectional dimensions of the proposed
tunnel and of a length equal to the section piled (see Figure 3), said tube being closed at
the ends with temporary diaphragms h of metal or wood and being also provided with
a middle diaphragm for the purpose of facilitating the sinking of the tube. I have
two chimneys or funnels J built out of the tube H, one at each side of the diaphragm h¹.
They are carried to such a height that they stand above the surface of the water when
the tube is sunk. They are closed at the top and are provided with valves (not shown)
for allowing air to escape from the tube.
These chimneys are mainly provided to facilitate the sinking of the tunnel tubes,
by enabling the tube to be gradually sunk without losing its power of flotation.
In each division of the tube I place two valves for admitting water therein, the said
valves being operated by suitable lever or other connections from the tops of the
aforesaid funnels. The tube may be either constructed with sufficient bracing of
angle, or other shaped, iron to prevent change of form, or it may be temporarily
strutted internally with timber.
The tube, being constructed on shore and launched, is moored over the rectangular
space prepared for it, and sunk. The space remaining between the tube and the piling
is then filled with concrete, masonry or the like.
Another section A, of the tunnel bed, is then piled and excavated, in a similar
manner to the aforementioned. The sheet piling B' between the two lengths is then
removed and the second length of tube deposited as close as possible to the first length,
this proceeding being repeated till all the lengths have been executed.
I then pump
the water from the tubes and remove the diaphragms h and h¹, the concrete making the
tubes sufficiently water-tight to do so. To prevent any permanent leakage at the
junctions of the tubes, I connect their ends as follows (see Figures 4 and 5):-
I enlarge the internal diameter of each end of the tubes, as at h³, and at a short
distance from the end of this enlargement, I place an inner angle iron ring ³ which
may be conveniently utilised for attaching the temporary diaphragm haforesaid.
When two tubes are set in line in their excavations, the angle irons h³ will come
opposite each other, as shown in Figure 5, but at a variable distance apart due to any
inaccuracies in setting the tubes.
When the water is pumped out of the tunnel, I measure the exact distance between
the angle irons h³, prepare a flange plate * to fit in between the same, and rivet the
flanges of said plate to the angle irons, as shown. The plate /* then forms a water-
tight joint.
The tunnel tubes may be made of any desirable shape in cross section. K are the
rails which are secured to the bottom of the tunnel in any convenient manner.
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:-
1. The method of constructing submarine or submerged tunnels, consisting in piling
the course of the tunnel across the bed of the water-way and dredging a trench between
the rows of piles or otherwise forming a trench for the tunnel, sinking lengths of
tunnel tube end to end into said trench, surrounding the lengths of tube in the trench
with concrete, masonry or the like, removing the water or other sinking medium from
the tubes, removing the closing diaphragms (if used) therefrom, and covering the
junctions of the tubes, where required, with an internal water-tight ring, substantially
as described.
2. A submerged or submarine tunnel constructed of a series of metallic tubes laid
end to end in a hollow-way, suitably jointed at the junctions, and the remainder of the
hollow-way filled with concrete or the like, substantially as described.
Dated 171 1
Ր A 1900
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, and London, Patent Agents.