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Engineering
wonder
The Scheme is widely regarded as one of the engineering
wonders of the world. Teams of geologists, hydrologists,
surveyors and engineers, collected, and analysed information
about the natural and built environments. Many innovative
techniques and pioneering solutions to problems were
developed on the Scheme. Because many techniques, including
some that were developed specifically for the Scheme,
had not been used in Australia before, the project had
an enormous impact on the development in Australia of:
- surveying
- hydrology
- electrical
and
- civil
engineering and construction.
Activity
Comment on the importance of communication between specialist
engineers when involved in such a complex project.
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Surveying
Aneroid barometric levelling
Barometric levelling is a method that allows surveyors
to find elevations on the earth's surface by recording
differences in air pressure.
The
application of the barometric method is suited
for work in difficult terrain. Wallace and Tiernan
altimeters were used by Scheme surveyors to determine
the heights of a large number of vertical points.
Universal
Theodolite Wild T2
A theodolite is an instrument for measuring horizontal
or vertical angles. As the name suggests, this
theodolite had many applications. It was also
an exceptionally stable instrument, which enabled
it to be used during extreme temperature and climatic
changes.
A
feature of this theodolite is that it is interchangeable
with many other Wild instruments. Surveyors could
use this theodolite in tunnel alignment determinations
and with a sub-tense bar, for measuring distances.
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German surveyor using a Wild theodolite
at the Island Bend dam site (1951) (Raymond, 1999:
71) |
Tellurometer
(Model MRA 101, S/N 113) - Electronic Distance Measurement)
The tellurometer was designed by T.L. Wadley in
South Africa (1957), and was introduced to the scheme
during the same year. It allowed surveyors to determine
distances by measuring the time electromagnetic
waves travelled between the master and reflector
units, and back again. The measuring range was from
200m to 40km. |
Tellurometer
panel (SMA) |
Activity
Investigate the role of a surveyor and indicate what
assistance they can be to engineers. For example what
information do they supply to engineers. The web site
for The
Institution of Surveyors Australia may be useful.
Hydrology
The chief innovations in hydrology (as distinct from
the various techniques used to gather and test water
samples) was in modelling the flow of water, and its
impact on dam structures, soils, etc. When the Snowy
Mountains Hydro-electric Authority (SMA) was established,
the Scientific Services Laboratory was set up on the
southern edge of Cooma. Scientific Services, as the
division was known, had a number of laboratories within
it, including the Fluid Mechanics Laboratory, where
models of dams, watercourses, spillways, etc. were built
and where hydrological experiments were carried out.
The laboratories have closed, but during the construction
of the Scheme (1949-1974) the investigations undertaken
in the laboratory were crucial to the construction of
the Scheme. The film, Science Serves the Snowy,
has a section on the Fluid Mechanics Laboratory, and
is probably the best available archive for the visual
representation of the hydrologic modelling undertaken
by Snowy engineers and scientists.
Electrical
Guthega: the first power station
The Snowy Mountains Scheme, which commenced in 1949,
is located
geographically approximately midway between the two
major load centres of
Sydney and Melbourne. Both the states of NSW and Victoria
were totally
separate entities in terms of electrical power generation.
The first Snowy Power
Station (Guthega, 60 Megawatt output) was connected
to the NSW power grid
by a 132 kv transmission line in 1955, providing valuable
electrical energy at a
time of great post-wartime shortage.
Tumut
1 Power Station
Tumut 1 Power Station followed in 1959, with an installed
capacity of 329 Megawatts. This provided the opportunity
for the first significant injection of power into both
State power systems.
The
transmission distances were significant and future power
blocks from Snowy stations were also to be considered.
Victoria had already established a 220 000 volt transmission
system while the Electricity Commission of New South
Wales had the task of linking up many local councils
and establishing a state of NSW grid.
A
330 000 volt transmission system
It was the work of Dr Walter Diesendorf (System Design
Engineer) for the SMAwho carried out studies using
the very earliest of computers to undertake complex
calculations. His innovative work resulted in a recommendation
to establish a 330 000 volt transmission system, connecting
the Snowy Mountains Scheme to Victoria at Dederang where
it was then transformed to 220 000 volts, and to Sydney
where the new 330 000 sub-stations were established.
As a result of this work, a group of SMAstaff transferred
to the Electricity Commission of NSW to establish their
original Transmission Division.
This
was a bold and innovative plan, which faced significant
scepticism initially. This extra high voltage level
was at the leading edge of technology at the time. The
first 330 000 volt cables were manufactured in England
and transported to the Tumut 1 Power Station site where
they were commissioned and linked to the underground
transformers with the transmission line.
Electrical
insulation problems
There were many problems to be solved with electrical
insulation for the transformers:
- insulated
bushings which are fitted to the transformers
- oil
filled 330kv cables
- lightning
arrestors
- design
of the switchyards to ensure adequate design clearances
between conductors.
Extra
high voltage
Such innovative and far sighted engineering design,
was considered to be at the forefront of technology
which challenged designers and overseas manufacturers.
Extra high voltage was in its infancy in the early 1950s.
Subsequently, in present day design, the lessons learned
have resulted in pressing the voltage limits of electrical
plant higher and higher. It was interesting that the
SMAimposed a 1 000 000 volt test on the 330 000 volt
cables prior to them going into service. These cables
and the transmission system have been in service now
for almost 50 years.
Civil
engineering and construction
Rock drilling
Rock drills were used to bore holes in rock in readiness
for gelignite insertion, and to cut away rock structures
to prepare for the construction of dams, tunnels, roads,
and power stations. There were many rock drill designs
and drilling techniques. These designs have influenced
the design of the modern masonry drill bit.
There
were many shapes to the cutting edge of a drill bit.
The type of work to be undertaken determined the shape
of drill bit to be used.
(Raymond, 1999: 38)
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Activity
Sketch and label the parts of a modern masonry drill
bit for domestic use. Comment on the shape of the cutting
edge. Identify the cutting edge material.
Rock
bolting
The technique of rock bolting was one of the many innovative
engineering achievements used on the Scheme. Rock instability
was prevented by using rock bolting.
The
properties and behaviour of rock played a major role
in determining the design and construction programs
that were adopted. Steel bolts of different lengths
and spacing, were inserted into the rock where they
were found to be an excellent anchorage for the rocks
in tunnels.
(Raymond, 1999: 49)
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Tiltmeter
(Galileo, Italy)
This instrument was used by engineers to record
the extent to which a concrete dam would tilt during
grouting operations and filling with water. It was
also used by geologists to measure the abrupt upheaval
of strata from the horizontal. |
Tiltmeter. Courtesy: Snowy
Mountains Engineering Corporation
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Slide
rules
One commentator has remarked that the Snowy Mountains
[Scheme] was built mainly with slide rules. The
cylindrical rule was developed by George Fuller, Professor
of Engineering, Queen's College, Belfast.
SMEC
In 1970, the Snowy Mountains Engineering Corporation
(SMEC) was established in order to retain the engineering
and scientific skills that were gained during the development
of the Scheme. SMEC was set up on the site of the old
Scientific Services Laboratory on the southern edge
of Cooma. SMEC is still there and undertakes work throughout
Australia and overseas building dams, tunnels, and carries
out geological and soil mechanics investigations. In
1993 SMEC
was privatised. It is owned entirely by its staff.
Today
SMEC is involved in many projects throughout Australia,
the Pacific, Asia, Africa and the Middle East undertaking:
- studies
- investigation
- design
- project
implementation
- management
- training.
(SMEC, 2000)
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