IMPROVEMENTS IN THE CONSTRUCTION OF BRIDGE PIERS, WHARVES, DOCKS, AND OTHER HYDRAULIC STRUCTURES, AND IN APPARATUS THEREFOR
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by Peter Jensen at the Office of the
Commissioners of Patents, with his Petition, on the 15th May 1872.
A communication from abroad by Detleff Carl Eduard Steinbrenner,
of Aarhus, in the Kingdom of Denmark, Civil Engineer.
I, PETER JENSEN, of 89, Chancery Lane, in the County of Middlesex,
Engineer and Patent Agent, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF BRIDGE PIERS,
WHARVES, DOCKS, AND OTHER HYDRAULIC STRUCTURES, AND IN APPARATUS
THEREFOR," (a communication to me from abroad by Detleff Carl Eduard
Steinbrenner, of Aarhus, in the Kingdom of Denmark, Civil Engineer,)
to be as follows:-
The first part of this Invention consists in constructing a working
platform to be used for building a bridge across a stream or other piece
of water. For this purpose two narrow timber floats, each consisting of
longitudinal and cross timbers bolted together, are constructed on shore
and gradually pushed out in the water at the place where the bridge
is intended to be built till they reach the opposite shore. They are
kept a distance apart suitable to the width of the bridge. When the
floats aro in the intruded position resting on the shore at each end, they
are weighted down by means of stones tied on by means of galvanized

page_text: The next part of this Invention consists in the application of it to
the construction of harbour piers, sluices, wharves, and other hydraulic
structures. In front and at each side of the object to be lowered into
the bottom of the sea or river are placed scaffoldings, consisting of piles
having blocks of wood at their base, if required, to give a broader bases
for soft bottom soil. They are surrounded by and pass freely through
holes in a lower and an upper wood frame joined by diagonal cross
timbers, and the upper frame being above water; the piles have each at
'their upper ends a vertical row of holes in order to raise and fasten the
upper frame by and to them by means of bolts. On the frames is placed 1
a mould box; balks of timber keep the framings the proper distance
apart and serve to hold the moulding box. In order to obtain a perfect
map or counterpart of the bottom of the sea, the following apparatus is
used. It consists of light timbers lengthways and of light timber
crossways in number corresponding to the cross divisions in the object 1
to be lowered. Ordinary boards are nailed on and under the timbers:
The said top and bottom boards are perforated with holes about 1 inches
diameter, and taper-ended sticks pass through both sets of holes. In
order to prevent them from sinking too far in the soft mud there may
be in the middle of of the taper a small flat angle and about 1 inch wide
and 2 inches long. Springs are fastened at the holes against the sticks
(which have pawl notches) in order to keep them from going back but
without preventing them from passing up. The apparatus is put together
on shore, floated to the place between the two scaffoldings aforesaid, and
lowered by means of a rod at each corner, or by weighting if required; ¿
the corner rods are then water level marked, the weights removed, and
the apparatus raised again, putting the marks in level; a perfect picturé
is obtained of the bottom by the position of the taper bottom ends of the
sticks. A shoe corresponding to it can now be made, consisting of
timber lined with boards so that it can be cut or have additions made to
it to suit inequalities of the bottom. Should the latter have a rather
large inclination a corresponding tapering plank may be put on. The
shoe is provided with straps for taking hold of for lowering, and when
ready is lowered in its place; the mould box is placed on it and the
concrete casting proceeded with, as explained with reference to the
bridge. When thus one piece is finished the scaffoldings are moved to
the next and so on. The hollow spaces leſt in the concrete, if any, are,
when the latter is sufficiently set, filled with earth or rubbish.
•

page_text: In order to avoid mishaps by stormy weather, a temporary floating
breakwater is fastened to shore at one end till one piece of the structure
is finished; it is then fastened thereto, its other end being moored by
an anchor.
Another mode of building, especially for wharves, docks, and sluices,
is as follows:-A sufficient number of piles are driven in a slanting
direction. Scaffolding and mould boxes are then applied, the former
consisting of small cross timbers with two longitudinal timbers on the
top of them. The mould boxes are arranged on them together with
a gallows having two pulleys; a chain runs on them fastened at one end
to the shoe, and at the other to a winch; the shoe is thus lowered as the
concrete castings proceeds; or, for large castings, straps may be used
instead of chains. To enable the cast block to slide on a previously
formed block, the former may have a wood block or blocks to slide with
against the latter. At top there is also a mould block made of two
wedges passing upwards and one wedge passing downwards, thereby
enabling the concrete block to slide and also forming an opening which
is afterwards filled with cement; two other openings are also left to be
thus filled afterwards, all serve to bind together the blocks.
By means of drain pipes a hole is left for a bolt to pass through to the
anchor at the abutment. If anchors are to be avoided and the abutment
is to be self-sustaining, the inner side of the abutment should be vertical,
or nearly so, and the outer side slanting; the concrete blocks would
then have to be cast broader below. The outer side of the mould box is
then made of the required taper; a night after one casting is made the
block is lowered the depth of the mould box which then has a partition
put in to make it smaller, and so on.