The Chitina leader., 1911-08-05

| thS ShIiiS iiilS UelWeen lax TOlnC
and Miles Glacier on practically lev
ell ground; and in the event of the
construction of the line to the coal
fields near Katalla. seven and one
half miles of construction would be
saved, with decrease of fifteen
miles in the coal haul, and practi-
cally no increase in the haul from
the copper mines on the upper Cop
per river.
At the Flag Point bridge. the
range between high and low water
is feet
After Mr.. Hawkins approval of
the selected crossing, a party under
Assistant Bridge Engineer ]. r.
Preble, was sent to the proposed
bridge site. and on April Is, 1908.
began taking soundings of the river.
through the ice for distance of one
half mile each side of the tentative
crossing and taking accurate topo-
graphy of the river banks for the
same distance. This showed our
tentative crossing to be the economi-
cal one. Wash drills We're then
made every two hundred feet he
tween shores which showed nothing
but sand and gravel for depth of
ninety feet. This work was all done
from the ice. The ice broke up and
began to move on May %.
1t was decided to build steel
steel bridges by company force
After the track had been laid to
| the Copper river the temporary
trestle was driven parallel to the
bridge tangent and 81 feet down
stream This trestle was completed
July 4th, 1908. 1t was decided to
| span only the main channels with
steel, and maintain wooden trestles
on the bars. On account of the
heavy ice (from four to eight feet
thick armored ice breakers were
designed, and the sides of the piers
were armored to high water eIeva-
ton as shown on the plans Pile
foundations We're decided upon for
all piers and abutments. On July
LIST, 1908. C. n. Mcdonald. General
| Foreman, reached the work and &C
tual construction began. In driving
| the piles for the temporary trestle.
! il was difficult to secure pile pen
etration exceeding 10 feet. therefore
i in sinking the piles for the masonary
foundations. two inch water jets,
each supplied with a Wagner boiler
feed pump, 2 y inch discharge were
used, one on each side of the pile
and at the same time hitting the
pile short blows with $500 pound
| hammer. The average penetration
of the piles for the masonary foun-
dations is SO feet below cut off;
maximum feet; minimum 33 feet
After beginning construction. it was
decided TO omit piers 4. 10 and II
and abutment 2; spans No. I, Sa
and 8, as it was thought pile trestle
could be maintained here for the
present. The excavation for all the
piers, except l and IL. We're made
largely with and inch Morris
sand and gravel pumps. The depth
of the water at piers 1 and - was
great enough that the pile cutoff
was above the bed of the river. y
rock quarry was opened up. five
miles from the bridge site. from
which very hard quartsite was OBJ
Jained for the concrete and for rip
n ba nj Z
used for the concrete was that oh
tanned from the excavations. The
river froze on October 18th, 1908,
rendering further construction i'm
possible During 1908. we completed
pier 8 to a point above the water
level.
We resumed work on this bridge
April LIST, 1909, and began erecting
spans No. 10 and No. II on April
10th. completing these two spans
May LIST, except riveting the floor
system. For four days of this time,
the wind blew in excess of sixty
miles per hour, an- no work could
be done. These two spans were
erected on false work on the ice.
We also began and completed piers
and I before the ice went out of
the river.
The ice in the river broke up and
began to move on the 2Sth day of
May, or on exactly the same date as
in 1908. The remainder of the piers
were completed and the steel erect
ed and all riveting completed on
August 10, 1909. Six of the nine
spans were painted with two coats
of paint, and the other three with
one coat only, on account of winter
setting in Marine Tockolith paint
was used for the first coat and w.
I. R. waterproof for the second coat