The Topeka state journal. [volume] (Topeka, Kansas) 1892-1980, 1906-04-14
RAILROAD NEWS.
Noteworthy Engineering Feat on
the Belen Cut-Of.
Great Bridge Being Built Over
the Treacherous Pecos.
UNIQUE FOUNDATIONS
Preliminary Work of Great Elk
tent and Costliness.
Gossip and Matters of Interest
in Railroad Circles.

Work on the building Of the East
ern railway Of New Mexico, which is
the official title for the Santa Fe
Belen cut off, continues TO arouse all
sorts of interest among railroad men
and persons in general This is due
Largely 10 the extraor 15nary thorough
ness and perfection aimed at IN its
construction The great bridge across
the Pecos river at sunnyside, n NJ,
viii well illustrate the character Of
the work. The Pecos at the point to
be bridged flows a shallow stream over
a broad sandy bed between widely
separated banks considerably lower
than the adjacent country on either
side In approaching the stream fer d
suita bic point for bridging the locating
engineers had the problem of main
tanning their maximum grade Of SIX
tenths of one per cent, while not plac-
ing the bridge level unduly nigh
above the river. In the working out Of
this problem several surveys We're
made until the present location was
determined upon whereby in wide.
sweeping curve the embankment
reaches the east border Of the river
opposite a prominent headland IF the
west
At the point described the opening
to be bridged measures $500 feet be-
tween the river banks. proper. of
which distance HOO feet will be a
trestle afterwards to be earth filled,
7 and the remaining 1900 feet will be
spanned by a mighty steel structure
resting upon sixteen cOncrete piers
at an average height of seventy feet
above low water level.
The preliminary work is of great
-fsEr5
/ driving of a forest of piling, five piles
abreast, entirely across the river bed
to a depth of from fourteen TO thirty
five feet beneath the surface, the erec-
ton upon them Of a timber bridge
having the stability of such bridges
{ ordinarily in permanent use on rail-
roads although in this instance it VIII
serve only as the means of putting in
J place the great steel structure that IS
: to supeFsede it. And. further. a sec
ond bridge Of piling is thrown across
+ the river alongside this greater one
I just described, this latter at height
of ten feet above water. solely for the
purpose of Transporting materials for
the permanent structure to the point
where desired for use in its building
It is stated at the works that this
preparatory expense in the temporary
bridge VIII reach above $4,000 while
ne permanent bridge VIII cost fully
$500 600.
charge at the river crossing began ex-
plorattons beneath the surface in
search Of foundations sufficiently sta
Die to carry the enormous weight to
be placed above it and beyond dis
Nurbance by floods. This was done by
the driving of steel tubing at stated
distances from one bank to the other
penetrating the soil to such DEPTHS as
would reach the solid rock or sub
stratum hard enough to satisfy engi-
nee1lng demands. on the west bank
rock was encountered at a depth of
from y to 20 feet for a distance of 500
feet when suddenly bottom fell OUT
Of the river Thence eastward founda-
tons were located upon the substratum
at depths Of p to 80 feet.
In preparing TO build one of the mas
siNe bridge piers an excavation is first
MADE ia the sandy river bed until wa
ter Is encountered. Then steam pile
drivers proceed to hammer into the
earth a box or Golfer dam of heavy
sheet piling reaching 20 to 80 feet be
low water surface. Once enclosed this
dam is emptied Of the sand and water
by pumps raising a constant stream of
II Inches in diameter and by dredge
buckets swung from a steam derrick
hosting half a carload at a plunge. In
this excavation is then driven round
piilng set closely. and upon this is
empted car after car Of concrete.
forming as it hardens one solid block
q artificial rock In a similar manner
the Construction of the piers is carried