Perrysburg journal. (Perrysburg, Wood Co., O. [Ohio]) 186?-1965, 1888-07-13
THAMES RIVER BRIDGE.
Ono of the Most Dincult Engineering Fcats
ENcr Accumulated.

|
Ever Accomplished.
The building OF the new bridge for
tho Shore Line across the Thames
river at New London, Conn, is an en-
terprise which will interest engineers
and the public generally, as il is to be
one of the largest draws in the world,
and remarkable for the application of
original devices to overcome local diff
culties. The project is not new one.
and 1t has cost generation of talk,
planning, and the overcoming of the
obstacles of both nature and man to
bring IL TO the point of beginning work
n few weeks ago, and tho work will
probably be completed in two years.
| The Shore Line road from Boston to
New York by the way of Providence,
| has been Objectionable from the Begin
ming on account of the number Of fer
ries, and the one across the Thames is
| the worst and last to be abolished.
There has always been danger here, es-
| pecially in the spring, when the steam
fcrry-boat has frequently had to strug-
gle to avoid being swept into the Sound
with its freight of cars and passengers.
A. p. Bollcr, of New York, was engaged
to make the plans for the new draw
bridge several years ago, and the de-
tails were arranged for the beginning
of the work in 1888; the project had
the approval of the commissioners, but
just as building was to begin, interested
persons failed to agree. Nothing was
done till 1887, when the road decided
on double-tracked bridge, which was
another advance, rs only Il single track
had been previously proposed.
Winthrop's Point, half Il milo above
the present New London station, where
the Thames is the narrowcst, has been
chosen as the location. The place is
familiar to hff who have seen the Yale
Harvard rcgattas, for the finishing line
is only n few feet away. The Govern
ment navy-yard, which was established
few years ago above the site of the
bridge, has required notifications in tho
drawbridge to admit the huge war ves-
sells through. To allow this the swing
spans of the draw will be 502 feet long,
and afford two clear passageways for
ships of 225 feet each. The draw itself
is reversible, which saves much time
and is of itself difficult method on ac-
count of the double track, and is APP
piled here for the first time. The full
length of the superstructure is 1, ,422
feet, and it will be of steel throughout
OF n quality admitted to be the best by
engineers who have made n special
study of the composition.
The depth OF the water along the line
of the foundations ranges from 5 to 81
feet while the depth of the soft mud is
from 10 to so feet. The usual method
of foundation can not be followed in the
case of each pier. The pneumatic pro-
cess or putting down by air." as it is
called, could not be used without the
enormous outlay that is demanded after
n certain depth has been reached. The
engineer has succeeded in removing the
local difficulties by the application of
original plans. The method in brief is
TO sink an immense timber curb into the
mud at the bottom of the river, fill it
lllll VI plltS, WHICH 1tTC W Dt CuJ Oll db
the surface of the mud, and upon tho
heads of these found the masonry. The
mud within the curbs having been ex-
cavated, the spaces around the heads of
the piles will be filled with concrete,
which will bind the whole together and
form substantial base upon which to
found the masonry. The timber curbs
alone are immense structures, the one
for the central pier being seventy-one
feet square, and higher than most of
the buildings in New England cities.
The work of locating them in their
proper position at the bed of the river
is n matter of great eXactnoss, as tho
slightest deviation would be the cause
of much trouble and expense. The
work of the sub-structure, in short, is
the most important and most expensive.
Special machinery has been made, and
the number of engineering principles in
volved is greater than for any similar
enterprise yet constructed Spring
feld Republican,