IMPROVE- MENTS IN CONSTRUCTING THE FOUNDATIONS AND ABUTMENTS OF BRIDGES, PIERS, JETTIES, RETAINING WALLS, AND OTHER SIMILAR WORкS
Year: 1866

page_text: PROVISIONAL SPECIFICATION left by Willian Douglas Robotham at the
Office of the Commissioners of Patents, with his Petition, on the 10th
April 1866.
I, WILLIAM DOUGLAS ROBOTHAM, of Doncaster, in the County of York,
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN CONSTRUCTING THE FOUNDATIONS AND ABUTMENTS OF BRIDGES, PIERS,
JETTIES, RETAINING WALLS, AND OTHER SIMILAR WORкS," to be as follows:-
My Invention chiefly relates to the construction of abutments, piers, jetties,
retaining walls, and other large works which are built upon bad and treacherous
foundations, more particularily in bridging over canals, rivers, drains, and
watercourses, where it is desirable to keep the clearance as large as possible,
and in getting in the foundations where large and expensive cofferdams have
to be constructed. My abutments, piers, and other works may also be con-
structed where the foundations are good, but where masonary is expensive,
thereby effecting a great saving in time and presenting the appearance of a
good and substantial stone abutment.
My Invention more particularily applies to abutments for girder bridges,
and is carried out in the following manner:-I first screw a number of piles,
according to the size and nature of the structure, through the bad into the
good foundation, upon these piles I bolt a series of cast-iron plates, partaking
of the nature of so many girders, which have a bearing on the piles at one end
and are tied at the other to anchor piles with wrought-iron ties. All the edges
of these plates are planed to get a firm and good butt joint.

page_text: For the abutment pillars I carry up a rectangular box with internal ties,
on the top of which a cap is well fitted, which is the bed plate of the roller
bearing of the girders. These boxes are not necessary beyond that required
to take the girder. I carry up the wing walls in plates similar to the abut-
ment, all these plates are tied and cross tied, some to each other, so that the
thrust of one counteracts the pull of the other, and the others are anchored
to piles screwed in at that particular line of thrust. The fixed bearing
abutment will not have to be so well tied as the expansion end, on account of the
central girder taking part of the thrust, the plates being bolted to that girder.
For piers on similarly bad foundations, when there are a number of arches
sprung, I screw four or other convenient number of piles, and erect thereon
a standard which carries rectangular boxes (as before described in reference to
the abutment pillars) with a cap cast at the required angle to take the brick
or stone arch or girder, as the case may be, the end pier will in this case in a
great manner be in equilibrium, the thrust of the arch counteracting the
thrust of the "muck." I do not think it necessary to enter into all the
variety of structures which can be built in the manner before described with
economy and despatch, but merely give the above as examples. Sometimes I
carry up the pillars as before explained, and attached thereto plates of circular
or curved shape, the arch of the plate being for the purpose of meeting the
"muck" thrown against it, the "batter" being two to one and upwards.
This arrangement is perhaps stronger and cheaper than that first proposed,
but the appearance is not so good.
The abutment or other structure may be protected from corrosion by asphalte,
clay, and paint, or otherwise.