Evening star., 1922-02-21
BRIDGE VIBRATION
LAID TOFLOOR|NG
Engineer Says Calvert Street
and KIingIe Road Structures
Are Not Dangerous.

The Calvert Street and Klingle
road bridges are declared safe by j.
Z. Greiner. Baltimore engineer, in
reports submitted to the Capital
Traction Company today.
Mr.. Greiner tells the company that
the unpleasant vibrations now felt
on the Calvert Street bridge are due
mainly to q rough roadway surface,
and will be relieved as soon as the
new flooring is laid
"On Ground of Esthetics."
Mr.. Greiner asserts that a new Cal
vert Street bridge ''at the present
time can be justified only on the
ground of esthetics and adaptation
to surroundings, and this question Is
one of opinion rather than of fact.
In a letter accompanying the re-
port on the Calvert street structure
Mr.. Greiner says, in part:
Asphalt Surface Suggested.
I'm our final recommendation we
ask your consideration of the sub
stitution of steel joists and laminated
floor with asphaltic wearing surface
and in the report give the estimated
first cost of such a floor system as
compared with the replacement of the
existing floor. The carrying out OF
this recommendation Will make
great Improvement and save consld'
rable in maintenance and future an
noyance as well as providing road
way surface just as smooth and good
as the approach streets. 1t is purely
question of policy and finances, as to
whether or not this change should De
made. If it is probable that the
bridge will be replaced with a more
N,-It h r
the next year or two, then the sug-
gested change would not be justi-
fed, but if the present bridge is to
be maintained so long as it viii
carry city traffic safely and salts
factorily to the public, then the sug.
economical. 1t will permit the use
of twelve-ton trucks on any part OF
the roadway
Discussing his report on the Klinglt
bridge. Mr.. Geiner says:
The bridge. owing to the smooth
new floor deck, is practically free OF
unpleasant vibrations. and is gener'
ally in a very good physical condition
requiring merely a few inexpensive
adjustments to make it as good as
new. These adjustments are mention
ed in the recommendations of the re
port.
THE structure is perfectly safe un'
der the traffic to which 1t is now sub
jected, and, in fact. as soon as the adi
justments are made you could. with
out any harm to the structure. IN
crease the car loads to $4,000 pounds
the truck on the floor to seven tons
and if run on the rails the trucks
need have no limit in weight up te
twenty tons. There is no necessity
for any speed restrictions for elthel
the cars or vehicles SO long as the
floor remains smooth.
R.r. ShnuJd Re Cleaned.
ION account, of the floor deck ant
joists being in good condition, we
have not recommended any change iT
character at the present time, bu'
suggest that. when the planking be-
comes worn and the joints require
renewal. you consider replacement
with steel joists and laminated f1ool
with asphalt wearing surface, sucf
as has been suggested for your Cal.
vert street bridge.
THE bars which show signs of cor.
rosion are not as yet in serious con.
dition, since there is sufficient sount
metal for the service loads, but these
bars should be cleaned and protected
as recommended in the report"