Arizona republican., 1922-05-11

These conditions called for the COM
pletion Of the slab during the period
between March and Jluy. AS instruc-
tiops to do the work by force account
were not received By the engineers
until the latter part OF January, 1921,
only five months were available to
secure the equipment, supplies and
laborers and lay the slab. Govern
ment restrictions in making purchas-
es. the almost complete denudation
of construction equipment and mate
rails due to the war. scarcity of COM
petent labo. and the remoteness Of
the work from centers Of population
offered perplexing and almost insur-
mountable obstacles. Government
equipment was woefully inadequate
and autiquatAd. At the start it con-
sisted of a few old tents, some cook
ing gear, Vim truck, and a Ford
car. both abandoned, and IL By ~
inch compre sor and motor. The pros
pect was anything but inviting to the
engineer who faced the task OF ex-
cavating 1851 cubic yards of earth
and rock. the mixing and placing OF
1888 cubic yards of mass and rein
forced concrete, and the driving OF
694 feet o. piling in five months
time.
Work Against Tine
The immediate an desSentlal re-
duirements were 20 complete exca-
vations, drive the piiing and pour
ing the main slab and talus of the
$3.50 cubic yards of concrete form
dam covering an area of 400 feet by
212 feet and feet thick. This had
to be done in the bed of a sandy
river. subjecL to frequent floods and
il had to be completed before July !
to prevent almost certain destruc-
tion, With q fixed time limit on the
lob the most careful planning of con-
struction methods was imperative.
During the excavation the engineer
in charge spent many days and sleep
less night in making preparation
for the concentration of all his forces
and equipment in the herculean task
of paving the wide stream bed with
its massive block of concrete over
which the ever threatening flood
pass harmlessly. Many methods We're
considered and Abandoned until fl
naily IL was decided to erect set or
tramways supporting a narrow gauge
track over which small dump cars
could be operated. Efficient and rapid
means of moving cars was secured
bv utilizine Ford motors. Four cars
NGlG Gtk1RPCA uA30 O44tRRS~
flange wheels and weighted with bro
ken Jaws Of an old rock crusher to
hold them on the track. When cou-
pied to the dump cars loaded with
concrete these motors proved eff
cient and ees nomical.
Two pairs of trestles joined at each
end, supported the track and rough
ly in the shape of an elipse or oval
were erected across the river. At the
end of each oval was erected a con-
crete mixer. The motors with dump
cars passed under the mixer spouts,
received their loads and then ran out
to dump the concrete into hoppers
which discharged into movable chutes
the slab. On June 5. 1921, the ac-
delivering c.'ncrete to any part Of
tual work Of pouring began. The OPP
Grafton OF the cars was admirable
a round trip being completed every
six minutes and straining the ca
pacity OF the mixers to the limit. The
operation of these motors and cars
was renaindful of roller coaster at
a summer resort and the noise was
very much the same.
Flood Threatens
Once fairly under way the work
was rushed with the utmost speed