Engineering Wonders of the World
Volume III
Forfatter: Archibald Williams
År: 1945
Serie: Engineering Wonders of the World
Forlag: Thomas Nelson and Sons
Sted: London, Edinburgh, Dublin and New York
Sider: 407
UDK: 600 eng- gl
With 424 Illustrations, Maps, and Diagrams
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142
ENGINEERING WONDERS OF THE WORLD.
SNOWSHED ON SOUTHERN PACIFIC, CALIFORNIA.
tween these points has a length of almost
twenty-one miles. The “ Omaha Cut-off,”
completed recently, takes the
The Omaha a|r_jjne route. The country is
Cut-off. 1 , ,
rugged and rolling, and the
hills are of a friable material known as “ loess.”
The drainage runs north and south, practically
at right angles to the line, and there are no
favourable water-courses for the line to follow
to secure lighter earthwork. With the ex-
ception of a few curves necessary to connect
with the old main line near Summit, and for a
similar purpose at the west end, the alignment
is straight, running over hills and valleys
regardless of topography and expense. To
build this line involved 2,800,000 cubic yards
of excavation and about 4,000,000 cubic yards
of embankment. In one case, in the crossing
of Big Papillon Creek, the embankment is 65
feet high and 5,600 feet long, and, with a
width of 300 feet at the bottom, contains
approximately 1,500,000 cubic yards. An-
other fill across the Little Papillon is 89 feet
high and 3,100 feet long. In this case the
original width at the bottom was estimated
to be 320 feet. But in the bottom of the
I
valley the soil is very soft, and rose up on
each side of the embankment as the latter
settled, adding nearly half a million cubic
yards to the first estimate.
An even greater work than the Omaha
Cut-off is the “ Lucin Cut-off ” over the Great
Salt Lake. The original route ran, as we
have seen, from Ogden round the north end
of the lake, round many curves, and up the
heavy grades required to surmount Promon-
tory and Kelton Hills. A short line along
the north shore of the lake was out of the
question, because of the extreme irregularity
of the same.