Year: 1886

page_text: I, FRIEDRICH HERMANN POETSCH of Magdeburg-Sudenburg, in the Empire of
Germany, do hereby declare the nature of my said invention and in what manner
the same is to be performed, to be particularly described and ascertained in and by
the following statement:-.
The object of my invention is to effect further improvements in relation to a
certain invention, for which Letters Patent were granted to me dated the 29th May
1883 No 2655.
And in order that my present invention may be particularly described and
ascertained, reference is hereby made to the accompanying drawings, in which
similar letters of reference indicate corresponding parts.
In Fig. 1. a represents a shaft in process of sinking; b is a shield, of any suitable
form and material, and so placed in the shaft that the space e is shut off from the
external air by means of any suitable material, at b and c, which does not become
brittle at any low temperatures. d is a pipe, which is well lagged, and through
which cold air is passed to the space e; such pipe d being in communication with
a refrigerating apparatus, whereby the aqueous strata to be bored is caused to
freeze, in a manner analogous to that described in the Specification to the said
Letters Patent No 265583. In this manner, after removing the material in b and c,
the frozen strata at the bottom of the shaft can be excavated to the extent of
3 feet or more, or until the limit of the frozen material is reached.
The shield b is then again lowered and the process repeated. This process is
continued until the shaft is sunk to the required depth.
In excavating a tunnel, the excavation is conimenced in the ordinary manner,
until aqueous strata is reached, after which a shield is formed as shewn in Fig. 2,
consisting of a double frame cc and suitable material b is introduced to render the
same airtight; the pipe & being used for the introduction of cold air, as before, to
the space e whereby a frozen block of the aqueous material is formed.
[Price Bdı

page_text: Another method of freezing the strata consists in sinking pipes in a vertical or
diagonal direction, as shewn in Fig. 3, on both sides of the tunnel a whereby
frozen walls are formed, and the intermediate material may be readily removed,
the superincumbent earth g being sustained by beams h and boards or planks i.
When the strata f (Fig. 2) is sufficiently frozen, the shield 61 c is opened to
allow the escape of the cold air and the entrance of warmer air, which may be
effected by a ventilator or otherwise, the tunnel being then further excavated and
the process repeated.
It is obvious that my said invention is capable of many modifications, according
to the nature of the work to be performed.
By the application of my invention to the construction of shafts, Bridge-piers,
Tunnels and analogous works, any suitable tubbing may be inserted, erected, or
provided, consisting of wood, metal, stone, glass, mortar or other suitable material,
to prevent the breaking in of the aqueous strata.
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
1. The application and use of refrigerating appliances, for the purpose of
facilitating and economising the excavation of aqueous earth or strata, by causing
the same or the surrounding strata to become temporarily frozen, substantially as
hereinbefore described and illustrated on the drawings.
2. The method and means of forming solid frozen walls and enclosed spaces
through water or aqueous strata, for the purpose of enclosing such spaces with
suitable tubbing, or effecting, other analogous operations, substantially as herein-
before described and shewn on the drawings.
3. The method and means of excavating and forming. tunnels and analogous
works, and erecting suitable walls and other permanent structures under the
protection of frozen walls, substantially as herein before described, and shewn on
the drawings.
4. The general arrangements and combinations of apparatus and the utilization
of the results arising therefrom, together forming my improvements in means and
appliances for sinking shafts, constructing foundations, bridge piers, tunnels,
excavations, borings, and analogous operations in aqueous strata or under water
substantially as hereinbefore described and shewn on the drawings.