The Key West citizen. [volume] (Key West, Fla.) 1879-current, 1938-04-20
H. E. Day. Tells lssrssass
Bridge Engineering Troubles
Addresses Service Club;
Club Votes To Pay $50
Of Telephone Bills For
Art Gallery

Characterizing the Overseas
Highway as the greatest single
asset TO South Florida. II. E. Day,
auditor with the Overseas Road
and Toll Bridge District. in an
address before the Service Club
last night told Of engineering and
ofbcx ditfgEViflaz IA IL.
other difficulties in the construc-
tion Of the bridges.
mo railway arch bridges have
ever been converted into high
ways, Mr.. Day said. This meant
that we had to branch out in a
new field. The bridges, besides,
had to be designed to suffer a
minimum of damage during hur-
ricanes. Well, we drew up plans
in spite of these obstacles for a
$4,400,000 fund which the PWA
was to furnish us. Then VIC
learned that 100000, which was
to be an outright grant was not
available at that period. This
was just one of the many OBJ
stacles the engineers hurdled.
They revised their plans in a
quick huddle, submitted them to
Washington, and they were APP
proved then finally"
Pointing out that the bitumin-
GUS retread material in the center
of the bridges is noticed by
motorists but that its purpose
is hardly known anywhere. Mr..
Day said this was part of the ex-
tcnsive planning for preventing
much damage 20 the bridges dur
ing hurricanes.
Hurricane Protection
"On either side of this retread
material are reinforced concrete
slabs, which are heavily anchored
into the viaducts. Below these
slabs are 9 inch Sits. The Sits
are to increase the space through
which hurricane winds can pass
besides going through regular
openings in the arches. If the
wind does increase far beyond
most hurricanes and the waves
get higher or if there are other
factors in a future hurricane
which will make it extremely
damaging then the first construc-
ton TO break away will probably
be portions of the concrete slabs.
This will leave the central part of
the bridge traverSable, and re-
pair can be made much faster
than If whole sections of the
bridges were wiped out.
The bridges are from 1880
feet from the water on the con-
crete arch construction, The deck
plate girder bridges are about 30
feet from the water. and there is
a third type OF railroad bridge
over which the highway was run.
a truss structure which in the
Bahia Honda Bridge is about 60
feet from The water.
In the Bahia Honda bridge it
was proposed Cd TO cut down the
superStructure and run road over
railroad bed GU make a one way
road over the top and another be-
low CD hang one way roads on
either side of the bridge "a
finally, run a two way road over
the top of the SuperStructure.
which has been done. The bridge
is the same height and type as the
ST. Johns River bridge at Jack
sonville, and local fears that it
would not be safe were con-
Sidered with some amusement by
Overseas engineers,
In Channel Number 5 draw
bridge. which was too high. por-
tons of the counter weights were
cut off and lowered six feet. then
a steel floor system added so that
wind resistance would be less
when the draw is open. II would
always be opened against the
wind as S. +. is the prevailing
wind there.
Big Job Ahead
The famous swing span" draw.
bridge which is of the truss type
was found to be too narrow.
The engineers split IL open and
pushed il apart to the required
width.
The District is just completing
a big job. Mr.. Day concluded.
but such clubs as the Service
Club have bigger jobs ahead Of
them in promoting civic and
Continued on Page Sikh
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