Improvements in and relating to Tubular Submarine Structures or Bridges.
Year: 1890

page_text: Date of Application, 28th July, 1890-Accepted, 13th Sept., 1890
CUMI LEIE DI DUITIOUATION
[Communicated from abroad by LA COMPAGNIE DES ETABLISSEMENTS EIFFEL, of
35, Rue Pasquier, Paris, in the Republic of France.]
Improvements in and relating to Tubular Submarine Structures
or Bridges.
I, HENRY HARRIS LAKE of the firm of Haseltine, Lake & Co. Patent Agents,
Southampton Buildings in the County of Middlesex, 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 tubular submarine structures or bridges.
The construction of railways, roadways and the like across broad estuaries and
straits, gives rise to difficulties of quite a special order.
For overcoming these difficulties use has heretofore been made either of tunnels
like the Mersey Tunnel, or of metallic bridges having long spans, like the Forth
Bridge.
This latter solution may not always be practical or possible especially by reason of
the difficulties or impossibilities which the foundation of piers at excessive depths
presents.
The solution by means of a tunnel may also be inadmissible either by reason of the
nature of the ground to be traversed or for such reasons of international defence as
have hitherto prevailed in England in the case of the Channel Tunnel and have caused
the suspension of the work in connection with the same.
The aforesaid invention which is designed to meet these various objections,
comprises a metallic or other casing A Figures 1 and 2 having an interior lining
of cement or masonry. The tube which is thus constituted and the form of which
can be varied for each particular case according to local circumstances, is sup-
ported and made rigid by a metallic bridge B placed in the interior of the
said tube.
In this manner is obtained a rigid structure which can be placed under water and
supported like ordinary metallic bridges by piers C Figure 2 arranged at suitable
distances apart according to the strength to be given to the bridge.
The improved submarine bridge is formed by immersing tubular sections of
suitable length and placing them end to end.
One of the particular objects of this invention is to arrange the successive tubular
sections at a depth not exceeding the depth at which work can be done under water
by means of compressed air apparatus for instance thirty metres for the lowest part of
the tube.
For this purpose, assuming that the bottom of the space to be crossed is at a
greater depth than thirty metres, piers forming frustra of pyramids are constructed
from distance to distance in any suitable manner for example by the aid of rock
work or blocks. The upper part, of these piers can be easily and accurately levelled
for example to the depth of thirty metres by means of compressed air-apparatus.
To the upper part of the said piers is given the reduced surface necessary for
serving as a support for the tubular bridge.
The tubular sections which are then put in place are generally made of great
length and may extend over one or more bays. These sections which have previously
been constructed in the yard are tight and hermetically closed at their extremities and
filled with air, so that they can float at first in order to be put in their proper
place. It is then sufficient to load them in a suitable manner for the purpose of
letting them down upon the piers.
A tubular section having been placed so as to form the prolongation of the
preceding section, the joint of the two sections is made either from the interior by

page_text: means of compressed air, use being made of partitions and sluices or air-locks which
have been provided in the said sections prior to their immersion, or from the
exterior by introducing the joint into liquid concrete or cement, which is effected
in a caisson' surrounding the extremities of the two sections situated upon the same
pier. By limiting the depth of the tube to thirty metres below the level of the
water any means adapted for using compressed air can be employed, it will therefore
be understood that I do not limit myself to the means bercinbefore described for
this purpose.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed as communicated to
me by my foreign correspondents, I declare that what I claim is :-
The employment, at depths below the level of the water not exceeding those
which are accessible to compressed air apparatus, of a tubular bridge which obtains
its rigidity by a metallic framework acting similarly to that of an ordinary bridge,
and which rests upon supports placed at suitable distances apart, and is surrounded
by a tight casing which prevents the access of water.
Dated this 28th day of July 1800
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.