Arizona republican. [volume] (Phoenix, Ariz.) 1890-1930, 1902-04-27


samples. No. /. 25S3 at 10 q, COM
pared with water of same temp. No. ,,
2.Gll at 14.5 =, compared with water of
same temp.
Tests for crushing were also made
ana are given elsewhere. The weakest
sample crushed nj IG14 tons per square
foot.
This rock is to be used in as large
blocks as practicable in order to make
The number of joints as few and the
quantity of mortar as small as may be.
It is estimated that the rock will oc-
cupy 40 per cent of the structure. Fiji
teen per cent will consist of cement
mortar in which the stones are bedded
and IS per cent will consist of cement
| concrete ramr-led into the vertical
| joints Taking the weight of the NOR
! tar as 115 pounds per cubic foot and
! that of the concrete as $50 pounds, the
| masonry will weigh a nearly as can be
estimated 146 pounds per cubic foot. On
| this estimate the strains have been
| computed and the section of the dam
designed. AS the dam is to serve as Il
! highway, a top width of 16 feet has
been adopted with parapets along the
sides. The section adopted is the small
| est consistent with the necessary top
the resultants of all forces acting upon
the dam shall be at all times within
! the middle third. The pressure on the
| tee when the reservoir is full, Will be
! 1919 tons PEI. square foot computed on
i Tho assumption that the dam is Il rigid
! mOnoith and non-elastic. Any elias
ticity it may have viii tend to relieve
| this pressure. The maximum possible
pressure. 1854 tons, occurs at the heel
when the reservoir is empty. with a
strong wind blowing upstream.
The above table shows fourteen in
stances with pressures greater, some
Of them many times greater, than those
/ in the proposed dam. The following
specifications are proposed for the
dam:
SPECIFICATIONS FOR THE con-
STRUCTION OF THE DAM.
DIVERSION OF THE RIVER. The
diversion of the river will be accomp-
Iished by means OF sheet piling driven
as deeply as practicable directly across
the canyon, beginning at the south side
and reaching as nearly as practicable
10 bedrock. the piling to be reinforced
at and above the surface by a heavy
wall of sand and gravel excavated
be diverted through the outlet tunnel.
which will be constructed in advance.
The gravel wall will he built at least
enc foot higher than the top of the out
let channel. and three-fourths of its
length, about 80 feet of the southern
end of the embankment being left at
an elevation six feet lower to be util-
lied as a spillway for excessive floods
which may occur too large for the ca
pacity of the outlet tunnel. The exca-
walton for foundation will begin at the
southern wall of the canyon, and as
rapidly as completed to solid founda-
ton will be filled with masonry. As
soon as 40 or so feet of the southern end
of the foundation is completed a wood
en- f1uTne will be placed at the above
/ mentioned spiIlway on the embank-
ment reaching down stream over the
completed portion OF the foundation,
! discharging into the stream bed at
least 300 feet down stream from the toe
Of the dam. This flume will be about
1000 feet long. and in that distance will
have fall OF nearly eight feet, which
will give it high velocity and enable
! it to discharge any floods likely to
occur. The pumps employed in drying
the foundation excavations will dis
piling cannot be driven deep enough tc
cut off the under flow pipes shall be
driven along the line across the canyon
and cement grout pumped in until tbs
desired result is obtained.
FOUNDATION. All earth. sand
gravel. boulders, disintegrated, loose
and scanned rock will be eXcavated and
removed from the entire area of the
base of the dam, in order to secure d
firm foundation on solid rock. Explo-
sivas shall not be used when eXcavat-
ing the rock unless absolutely neces-
{ sary and when used shall be only in
small quantities and in shallow holes
TO avoid fracture of the rock forming
; the foundation of the dam. The entire
foundation shall be thoroughly washed
with wire brooms, first with water and
then with thin grout. Throughout the
[ length of the foundations a trench six
feet wide and six feet deep, 10 feet from
: the heel of the dam, and parallel there
: to, shall be cut in the solid rock of the
foundation.
MASONRY. The main body of the
dam shall be constructed Of broker
range cyclopean rubble. The stone
shall be Quarried from the walls or
each side of the canyon. shown in the
drawing as proposed spillways. If 6
sufficient quantity OF hard, fine-graine6
stone cannot be obtained in These
spillWays it shall be quarried else
where. All stone shall be thoroughly
washed and laid in Portland cement
mortar. and each stone shall be laid OF
5 it's largest bed. The stone for the up.
| stream face shall be rough pointed sc
as to lay with horizontal beds and YER
teal joints. No mortar Joint in tbs
face shall exceed one inch in thickness
At least One-fourth of the area in thu
| face must be headers evenly distrib
uted throughout the WALL and every
header shall be laid over a stretcher o
: the underlying course. The stone shall
be so arranged as to form a prope
bond, in no case less than one foot
/ With the stone CT the underlying course
The stretchers must not be less than
= three feet long. nor less than two fee
in any other dimension. The header
+ must not be less than six feet il