The Republican. [volume] (Oakland, Md.) 1877-current, 1896-06-04
BROOKLYN BRIDGE is DOOMED.
When Vibration Ceases the Great Struc-
ture VIII Probably Fall.

ture Will Probably Fall.
The Brooklyn bridge is doomed. Civil
| engineers are specializing now as to its
length of life. Their attention has been
attracted TO it by the discovery that the
span of life of steel structure is dnuch
more limited than popularity sur bosed.
Its life is largely numbered by its
vibrations. 1t has been found that
every bridge can stand so MANY and
then the end comes like the Sudden
| stoppagc of a human pulse. In His la
boratory in Long Island city Prof.
| Alvah II. Sabin, an eminent authority
on the deteriorating influences that
steel structures are subjected II, is
| iaboring night and day to discover some
| protection against the dreaded effect
of corrosion and rust. His investiga-
tons have led engineers to turn their
| eyes to steel bridges, and more pafticu-
larly to the Brooklyn bridge, as its life
interests two cities. To engineers such
structures always appear lifelike, land
they refer to their birth" and nature"
and ailments" much the same as if
they were discussing the anatonyIof a
human being.
| Prof. Sabin said when seen: "There
are many deteriorating influences
which are even now sapping the dife of
the bridge. The principal trey.sas is
the care of the cables, because the other
parts which may be effected Dan all be
replaced little by little"
What precautions have been taken
to care for the cables?" he was asked
Il don't know what has been done
for them, but l do know that if they
are not thoroughly protected against
corrosion in some way they will GER
tainly wear away and become weak
ened."
a railroad engineer who was seen in
dorsed everything that had been said
by Prof. Sabin, and added: THE fact
of professional men making intricate
and abstruse computations as to the
probable life or period of actual dura-
| bility of the bridge does not imply that
it is unsafe or in any immediate danger
of falling into desuetude or collapse
/ The question is not hypothetical one,
but is founded upon existing influences
that are constantly tending toward de-
tcrioration and prospective results.
These may have sutficed to suggest a
doubt as to its durability.
The rushing train traffic on the
Brooklyn bridge, which is likely to be
doubled in the next few years, is has
tening this end, though it may yet be
many decades distant. The vibrations
resulting from this heavy train traffic
are beyond computation. They rarely
cease"
What other ailments threaten the
BRIDGE" was asked.
We'll, there are corrosion and rust;
they are enemies of all iron. The cor
rosion caused by the vapor from salt
water, which this aerial highway spans,
is the worst in form, and it's effect is
most dire in deStructiveness. The heavy
train traffic cannot fail to cause the
steel wire cables to sag in course of
time, while the iron saddles upeH. which
they rest on top of the towers must be-
come affected by both rust and corro-
sion. Once the action of corrosion sets
in the process of the chemical action is
very quick. The whole iron structure
is a moving one. The necessary provi-
sions for expansion and contraction by
heat and cold make it such. 7 hus there
is constant friction to be added to the
other causes of deterioration
How long will the Brooklyn bridge
| live?"
well, deprived of the heavy train
traffic, the structure might last for CEN
turiCs. But with the combination of
influences adverse to its durability it's
days of utility appear to be numbered.
1t may see the end of its usefulness in
so or 100 years, but it will always be
possible TO resuscitate and strength
en- it by using cantilever iron beams
beneath the big spans. This would
give new lease of life to the iron
structure.
THE indications are, however, that
long before the time for these antic-
pated changes arrives the bridge as it
stands now will have become entirely
inadequate for its intended purpose.
Coming generations are likely to see
the central portion removed and re-
rlaced by a douole-deck bridge, with
extension sidewalks running alongside
of the present approaches and outside
of the existing towers. The eXigencies
of the times will demand this. The pas
senger depots at either terminus of the
bridge have already had to be enlarged
and rebuilt on account of their in
capacity. The same causes will in the
future prevail in favor of other changes
for the accommodation of the steadily
increasing bridge traffic. IN. Y. Jour
nal.