Improvements in and relating to the Cutting of Underground Channels for Building the Walls of Subways and purposes.
Year: 1891

page_text: Date of Application, 17th Mar., 1891
Complete Specification Left, 16th Dec., 1891-Accepted, 16th Jan., 1892
PROVISIONAL SPECIFICATION.
Improvements in and relating to the Cutting of Underground
Channels for Building the Walls of Subways and
purposes.
other
I, GEORGE LAWSON, of Blairbeth House, Rutherglen Lanarkshire, Contractor,
do hereby declare the nature of my invention to be as follows:-
This invention has reference to and comprises a new or improved mode of and
meaus or construction and arrangement of appliances for cutting deep trenches or
channels in sand or clay or other approximately soft earths or ground and for
supporting the sides thereof as caissons, susceptible of considerable modification,
for and while building within these, foundations and walls of subways or other
structures, specially suitable for doing this in the streets of towns with little or no
vibration or obstruction to the streets and without requiring the travelling erections
of pile driving machines and appliances which are objectionable in such circum-
stances from the obstruction and vibration to the adjacent foundations and houses
inseparable from the use of these.
The nature and novelty of the improvements according to one construction consist
in first sinking a short piece of the channel or excavation, as say from fifteen to
twenty five feet, in the usual manner by manual labour with picks and shovels, and
supporting each side of the channel by the ordinary vertical lining of strong wood
uprights or piles, close up to these with inner longitudinal beams at intervals kept
separate by transverse beams to maintain the lining close up to the sides of the
channel with sufficient space to build a fresh piece, as say, ten or fifteen feet length
of the foundation and wall up to the full height desired and two feet or so wider
than the actual channel would subsequently require to be cut or excavated. The
new improvements consist in continuing the cutting of this channel or trench
forward in a longitudinal direction in the front of the end or ends of the piece of the
wall so built, by the use of a horizontal forward moving arrangement of longitudinal
sides to these channels, made in horizontal sections built or superimposed vertically
to slide forward over each other, each open at the back end to move parallel with
the wall but joined at the front end on opposite sides by a strong cross end or beam
with a bevelled pointed or excavating plate or end in front; which would support
the forward end of the channel as excavated by each section pushed forward over
each other as hereinafter described. One suitable construction of these excavating
and supporting side walls consists in forming vertical each alternate side section on
the opposite side of channel iron or steel with the web plate part of eighteen inches
or so deep, and the channel edge flanges six inches or so broad as their bearing and
sliding surface, that is, with the deep webs vertically over each other, close up
against the sides of the channel; and having the intermediate sections fitted between
these, formed also with a deep vertical web plate with angle irons rivetted parallel
to and on the inside of these plates about three or four inches from their upper and
lower edges. These angle irons rest on and carry the intermediate channel iron
sections by their upper and lower projecting flanges both sliding on these in their
horizontal reciprocating motion, the projecting edges of the web beyond these angle
irons forming parallel guides in their reciprocation, the webs of these intermediate
iron sections being outside the end plates of the channel sections close up to the
sides of the channel or trench. The front ends of these channel and angle irons on
opposite sides of the trenches are rivetted together by cross channel iron end plates
the whole width of the channel and in front of this a transverse or wedge shaped
plate is also rivetted to the upper and lower edge flanges of the end channel-bar, the
forward angled edge being on a line with the level of the underside of each section
angled up and back to the top flange of the cross plate to give a wedge or

page_text: excavating action to the cross end of each section to raise the material as it
was forced on into the earth in advance of the front end of the channel. The back
end of these horizontal and vertical sections which support the sides of the channel
are all left open to traverse parallel forward on broad vertical hardwood beams
secured close to near the front end of the wall last built, to retain them all at their
full parallel width, and guide them as they are pushed forward to make the front
wedge ends cut and excavate the end of the trench horizontally in advance of the
wall. In starting the cutting, these metal horizontal beam sections are all inserted
and built over each other in front of the temporary wood facing of the first part of
the trench, made wide enough as before explained, to allow of this insertion of these
new horizontal cutting sections over each other clear of the wood facing of the
channel with all the wedge close cutting ends close up to the advance end of the
channel and about two, three or four feet in advance of the front end of the last
built part of the wall. Vertical and horizontal beams would be erected on the
front of the wall and against these would be placed two or other number of
hydraulic jacks or equivalent hydraulic or other pressers with their front ends
acting within the cross channel beams of the cutting end of the upper section to
force it forward equally and parallelly at both sides on the cutting section below
step by step, at each working length of the hydraulic jack a new wooden block or
beam being put in behind the hydraulic jack at each shift, until it was carried out
to the full length of its side beams in advance of its back guiding hardwood
uprights and front end of wall, the earth forced up in advance of each section being
removed by pick and shovel or other hand tools and removed by barrows or buckets
and carts, the wall sustaining the strain of the hydraulic jack in forcing forward
each section in like manner under the first to the extreme position that it had been
forced to. Each subsequent upper section would be forced out until the bottom
section was reached which would cut the channel to the full depth forward the full
length of these horizontal shifting sections which would thus form the supporting
sides and front end of a new excavating length of the channel in advance of the
wall as a kind of caisson in which the foundation and new portion of the wall would
be built joining on to the end of the last piece, preferably by the usual tongue and
groove, "joggle," or other equivalent joint, to strengthen the wall at each new
section and prevent water passing through the joint. The "sump' or pump pipe
could be inserted vertically in front of each section of wall to pump out all water and
maintain the channel dry during the excavation of each length of the cutting or
channel; and a small portable engine and pumps might be removed forward on to
each section of the wall built, for working the hydraulic jacks, and keeping the
channel dry. Each advance section of the channel would be cut or excavated in
like manner to the first as just described, starting three feet or so in advance of
either or both ends of the wall to give space for the insertion of the hydraulic jacks
and sump pipe as stated. Although iron or steel horizontal sectional moving
frames have been described for cutting the channel forward in horizontal sections
it will be understood that these sectional side and end frames might be made in
hard wood bound together by iron knees or other suitable means and have iron
cutters fitted on the front end cross beams, and actuated otherwise all substantially
as described by horizontal hydraulic jacks or rams. Two sets of these superim-
posed horizontal traversed excavators may be used proceeding in opposite directions
from the opposite ends of the first piece of wall built; and each section may be
forced or drawn forward by other forcing gearing than hydraulics, as by powerful
toggle levers, screw presses, or chain pulley gearing and windlasses. Compressed
air or electro-motors may be used for the working of these appliances and the
pumps, in preference to steam engines when excavating or cutting channels or sub-
ways in streets to avoid the noise and inconvenience of steam engines.
Dated the 16th March 1891
"
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in and relating to the Cutting of Underground
Channels for Building the Walls of Subways and other
purposes.
I, GEORGE LAWSON, of Blairbeth House, Rutherglen, Lanarkshire, Contractor,
do hereby declare the nature of my invention, and in what manner the same is to
be performed to be particularly described and ascertained in and by the following
statement in writing that is to say :-
This invention has reference to and comprises a new or improved mode of, and
means or construction and arrangement and combination of appliances for cutting
deep trenches or channels in sand or clay or other approximately soft earths or
ground, and for supporting the sides thereof as caissons, susceptible of considerable
modification, for and while building within these, foundations and walls of subways
or other structures in sections, specially suitable for doing this in the streets of
towns, with little or no vibration or obstruction to the streets and without requiring
the travelling erections of pile driving machines and appliances which are objec-
tionable in such circumstances from the obstruction and vibration to the adjacent
foundations and houses inseparable from the use of these.
And in order that my said invention and the manner of performing or carrying
the same into effect or practice may be properly understood, I have hereunto
appended an explanatory sheet of drawings in which the same reference letters are
used to indicate corresponding parts in all the figures where shown.
Figure 1 shows a sectional side elevation; and Figure 2 a transverse section
taken on the line 1-1 Figure 1 of one arrangement of my improvements as in the
act of excavating a channel, and
Figure 3 is a sectional plan view as taken on the line 2-2 Figure 1.
Figures 4 and 5 are sections of the front ends of each of the two new or improved
alternate sets of sliding excavating frames C, D, corresponding to Figure 1 but to
an enlarged scale to show the construction more clearly, and
Figures 6 to 9 are views showing slightly modified constructions of the new or
improved sliding excavating frames C D.
Referring to Figures 1 to 5 of the drawings:-I first sink a short piece of the
channel or excavation A, to be formed as say from fifteen to twenty five feet, in
the usual manner by manual labour with picks and shovels, and support each
side of the channel A, by the ordinary vertical lining of strong wood uprights
or piles, close up to these with inner longitudinal beams at intervals kept separate
by transverse beams to maintain the lining close up to the sides of the channel
with sufficient space to build a short piece, as say ten or fifteen feet length of
the foundation and wall B B', up to the full height desired and have this piece
of channel two feet or so wider than the actual channel would subsequently
require to be cut or excavated to allow for the said supporting planking. The
new improvements consist in continuing the cutting of this channel or trench A,
forward in a longitudinal direction in front of the end or ends of the piece of
the wall B, B', so built, by the use of a horizontal forward moving arrangement
of longitudinal sides C, D, to these channels made in horizontal sections built
or superimposed vertically to slide forward over each other, each open at the
back end C, D', to move parallel with the wall B, B', but joined at the front end
on opposite sides by a strong cross end or beam C D³, both of the same channel or
U shaped metal construction with a bevel or V pointed or excavating double plate
or end C³ D³, in front, which would support the forward end of the channel as
excavated by each section pushed forward over each other as hereinafter
described. One suitable construction, as shown in these Figures 1 to 5, of the
side frames C, C, and D, D¹, forming the supporting side walls of the channel
section A2, being cut out of the earth, consists in forming. each alternate side

page_text: section on opposite sides of U channel iron or steel, as shown in Figures 2 and 4,
with the web plate part C about eighteen inches or so deep, and the channel edge
flanges c six inches or so broad as their bearing and sliding surface, that is, with
the deep webs C vertically over each other, close up against the sides of the
channel; and have the intermediate sections fitted between these formed also with
a deep vertical web plate D with angle irons d d rivetted parallel to and on the
inside of these plates about three or four inches from their upper and lower edges.
These angle irons d rest on and carry the intermediate channel iron sections C, c,
by their upper and lower projecting horizontal flanges c and d¹, both sliding on
these in their horizontal reciprocating motion, the vertical projecting edges d" of
the web D beyond these angle irons d, d', forming parallel vertical guides in their
reciprocation for both sections C, D, on each other, the webs of these intermediate
iron sections D being outside the side plates of the channel sections close up to the
sides of the channel or trench A, A, as seen in Figure 2. The front ends of these
channel irons C, c, and angle irons d, d', on opposite sides of the trenches are
rivetted together by the ends of the cross channel iron end plates C, D, the whole
width of the channel, and in front of this a transverse or wedge duplex shaped
plate C, D, is also rivetted to the upper and lower edge flanges of the end channel
bars C2, D2, at C" C, D" D11, the forward angled edge c³, d³, being on a line
with the level of the underside of each section, angled up and back to the top
flange C D of the cross plates CD to give a wedge or excavating action to
the cross end of each section to raise the material as it was forced on into the earth
in advance of the front end of the channel, and also support the excavated earth at
the front end of the channel as indicated at A₁ A in Figure 1. The back
ends C¹, D¹, of these horizontal and vertical sections C, D, which support the sides
of the channel, as indicated at A³, in Figure 3, are all left open to traverse
parallel forward on broad vertical hardwood beams E, E', secured close to near
the front end of the wall B, B₁ last built to retain them all at their full parallel
width, and guide them as they are pushed forward to make the front wedge
ends C³ ³, D³ ³, cut and excavate the end of the trench horizontally in advance
of the wall, as shown at A¹¹ in the upper part of Figure 1. In starting the cutting,
these metal horizontal beam sections C to C and D, to D³, are all inserted and
built over each other in front of the temporary wood facing of the first part of the
trench, made wide enough as before explained to allow of thus insertion of these
new horizontal cutting sections over each other clear of the wood facing of the
channel with all the wedge close cutting ends close up to the advance end of the
channel and about two, three, or four feet in advance of the front end B³, of
the last built part of the wall B B', as shown at A', in the lower part of Figure 1,
leaving room for the insertion of the sump or pump case as indicated at P, in
Figure 3. Transverse and longitudinal beams F, and F1, F", are erected on the front
finished end of each section of wall B B', as shown at B', in Figures 1 and 3, and
against these are placed two or or other number of hydraulic jacks G, or equivalent
hydraulic or other pressers, with their front ends acting within the strong cross
channel beams C, D, of the cutting end of the first upper section to force it
forward equally and parallelly at both sides of the cutting section below step by
step at each working length of the hydraulic jacks G, new wooden blocks or
beams F, F, of different lengths being put in behind the hydraulic jacks G, at
each shift, until it was carried out to the full length of its side beam in advance of
its back guiding hardwood uprights E, E, at front end B2 of wall previously built,
the earth forced up in advance of each section being removed by pick and shovel
or other hand tools, and removed by barrows or buckets and carts, the previously
built walls B, to B, sustaining the strain of the hydraulic jacks G, in forcing
forward each excavating section in like manner under the first to the extreme
position that it has been forced to, six of the top sections being shown as thus
forced forward in Figure 1, while the seventh section is shown in the act of being
forced forward, and the six lower sections are shown in their first position_as_not
yet forced forward in front of the last built section of the wall B to B. Each of

page_text: 22
these six lower sections would be thus forced out until the bottom section was
reached which would cut the channel to the full depth forward the full length of
these horizontal shifting sections and thus form the supporting sides and front end
of a new excavating length of the channel in advance of the wall as a kind of
caisson in which the foundation and new portion or section of the wall would be
built joining on to the end of the last piece, preferably by the usual tongue and
groove "joggle" or other equivalent joint, as indicated at B³, formed by concrete
cement to strengthen the wall at each new section and prevent water passing
through the joint. The "sump or pump case or pipe could be inserted
vertically in front of each section of wall as indicated at P, to pump out all
water and maintain the channel dry during the excavation of each length of the
cutting or channel; and a small portable engine and pump might be removed
forward on to each section of the wall built, for working the hydraulic jacks G,
and keeping the channel dry, wheu motive power pumps were used to move the
jacks G. Each advance section of the channel would be cut or excavated in like
manner to the first as just described, starting three feet or so in advance of either
or both ends of the wall B, B', to give space for the insertion of the hydraulic
jacks G and "sump" pipe P as stated. Figure 6 shows a plan view, analogous to
that shown in Figure 3, and lettered to correspond, but having the side
frames C, C, D, D₁, made simply of broad vertically disposed plates reciprocating
horizontally close up to but side by side over each other, as seen to a large scale in
the vertical section Figure 7, the outer wide plates D, having their lower and upper
edges resting and sliding on the upper and lower flanges of a channel
plate c¹ rivetted along the centre of the outside of the web plate of the intermediate
plates C, instead of the flange c in the former arrangement. These side plates C,
and D, slide or reciprocate close up to the sides of the last executed part of the
wall B, B', without the use of the vertical beams E, E', shown in Figures 1 to 3,
so that the frames D, D', in this case have no angle irons dd on them. Figures 8
and 9 show sections of the front cutting ends of the frames C, D, with their front
cutting cross beams C³ C³, D2 D3, shown in Figures 6 and 7. The channel
plates C, D, are rivetted by end flanges to the front ends of their respective
plates C and D, and the front cutting V plates C³, D³, are rivetted by
flanges C, D, to the front ends of the side frames C, D, and at C, D, to the
upper flange of the channel beam C², D³, otherwise the parts of this arrangement
Figures 6 to 9 are lettered and act substantially as described in reference to
Figures 1 to 5.
Although iron or steel horizontal sectional moving frames have been described
for cutting the channel forward in horizontal sections it will be understood that
these sectional side and end frames might be made in wood, bound together by iron
knees or other suitable means, and have iron cutters fitted on the front end
cross beams as at C³, D³, and actuated, otherwise all substantially as described, by
horizontal hydraulic jacks or rams. Two sets of these superimposed horizontal
traversed excavators may be used proceeding in opposite directions from the
opposite ends of the first piece of wall built; and each section may be forced or
5 drawn forward by other forcing gearing than hydraulics, as by powerful toggle levers,
screw presses, or chain pulley gearing and windlasses. Compressed air or electro-
motors may be used for the working of these appliances and the pumps, in preference
to steam engines when excavating or cutting channels or subways in streets to avoid
the noise and inconvenience of steam engines.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is :-
First. The method or system of cutting or excavating underground channels for
building the walls of subways and other purposes, in which are employed
5 longitudinal moving shield walls or frames composed of a series of longitudinal
sections built or superimposed vertically to slide horizontally forward over each

page_text: other, substantially as and operated in the manner and for the purposes herein
described in reference to and by way of application shown in the accompanying
drawing.
Second. In a system for cutting or excavating underground channels for building
the walls of subways and other purposes, the combination and use of a series
of horizontal moving sectional cutting and earth removing frames super-
imposed over each other, substantially as and for the purposes herein described
in reference to and by way of application shown in the accompanying drawings.
Third. In a system for cutting or excavating underground channels for building
the walls of subways and other purposes, the construction and use of sectional
excavating side frames working horizontally over each other bound together
at the front ends by cross front edge cutting beams, and open at the rear
ends to slide on walls or beams built up behind them, substantially as and
for the purposes herein described in reference to and shown in the accompanying
drawings.
Dated the 15th December 1891
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.