dredging project功能集合

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A major dredging project
130 million cubic meters to be moved for a
deepened and widened Panama canal that
can pass larger vessels
25 October 2006, in a referendum, the
Panamanian population approved of its
government’s proposal to spend 5.25
billion US Dollars on expanding the
canal.
This 80km long canal is regarded as one
of the world’s main engineering
achievements and its creation really
speaks to the imagination.
Around 1880, at the age of 74,
Ferdinand de Lesseps, the architect of
the Suez Canal, started his attempt at
his second canal. This attempt for a sea
level canal failed, fell in the hands of
promoters and speculators, and ten
years later the French company filed for
bankruptcy. Thousands of people had
perished during the effort due to
diseases such as malaria and yellow
fever.
After this, the U.S. supported a
revolution in Panama against Columbia,
who owned the territory and did not
want a US canal. In 1903 Panama
became an independent nation. In 1904
the Hay-Bunau Varilla Treaty allowed
the U.S. to build a canal and provided
the U.S. with perpetual control of a zone
of five (5) miles on either side of the
canal.
The U.S. Army Corps of Engineers led
the construction effort. One no longer
pursued a canal at sea level, but a
raised passage especially though the
mountains, using locks.
The Chagres river flowed from the
mountains into the Atlantic Ocean.
A dam was placed in the river and the
flooding of the area created a large
artificial lake, i.e. Gatun lake. During
nine months of the year heavy rainfall
on the narrow Isthmus of Panama
between the Pacific and Atlantic
Oceans, the lake collects enough water,
i.e. draining off allows for the locks on
both sides of the Canal to operate on
that principle. In a historic effort of
cutting the canal through the
mountains, thus creating the Gaillard
(or Culebra) cut, many millions cubic
meters of rock were dynamited and
removed in a major logistics operation.
The Canal was completed and in 1914
the first vessel passed through it.
Since then the canal has been
maintained, widened and repaired due
to landslides.
In 1977 US President Jimmy Carter and
President Omar Torrijos of Panama
signed a Treaty agreeing that the US
would transfer the Canal to the
Panamanians by 31 December 1999.
Both countries are to protect the
interests in the canal.
Since this transfer, the Panamanians
have worked hard to upgrade the Canal.
Tolls were raised to finance plans. The
canal is being straightened for safety
reasons as well. Scheduling efforts
since 2000 resulted in an increase of
20% in the passing capacity of the
Canal.
The locks, however, remained
unchanged. They were built in 1913 and
had a size of 1,000ft long and 110 feet
wide (304.8 x 33.5m). They include the
Miraflores and Pedro Miguel locks on
the Pacific side and the Gatun locks on
the Atlantic site, and to date they still
never fail to impress visitors.
The width of the locks, 110ft (33.5m)
became a shipbuilding dimension. Ships
built to that width comply with the 100ft
width permitted are classed as
“Panamax” vessels. A Panamax
container ship can carry about 4,000
TEUs (20' containers). World trade,
however, created a need for larger
vessels. Today an increasing number of
vessels that exceed Panamax
dimensions are being built and the
market research of the Panama Canal
Authority has shown that Post Panamax
vessels that do not fit their locks were
taking other routes around the globe.
In million m3
Capital Dredging
French Construction 1881-1903 59.7
US construction 1904-1914 177.4
Improvement Dredging 1930-2002 92.1
Maintenance Dredging
1915-1978 461.7
1979-present 20.8
Emergency Corrective Dredging
Landslides 1904-present 61.7
Total volume moved 873.4 *
*ACP: WEDA conference 2006
CSD JFJ DE NUL sailing through the
Panama Canal
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To secure the leading position of the
Canal and to maintain this waterway as
a route of choice the Panama Canal
Authority developed a plan to widen
and deepen the canal and create new,
wider locks. Such locks would consume
so much water that they could no longer
solely be fed by rainwater from the
Gatun Lake. A new system using water
saving basins was designed for the
180ft wide and 1,400 feet long locks
(55 x 427m) preserving the locks drain
water. These locks will be able to pass
post Panamax vessels carrying 8,000
TEUs.
The IHC-built TSHD BARENT ZANEN dredging in the Pacific side entrance channel of the canal
The cutter suction dredger MINDI improving the canal passage
The dipper CHRISTENSEN removing blasted rock
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Canals for the new locks will be dug,
parallel to the existing locks, which also
are intended to continue to serve the
water traffic. The lake’s level will be
raised and widening and deepening of
the Canal will involve the Gatun lake,
the Culebra or Gaillard cut through the
mountains, as well as both Ocean
entrances of the Canal outside the
locks.
For the new locks, the entrances and
the canal itself 133 million cubic meters
of material are planned to be removed.
Once completed, more than one billion
cubic meters will have been moved for
this Canal!
The Master Plan of the Panama Canal
Authority shows more detailed plans for
its excavation efforts. It is estimated
that about 50 million cubic meters of
the 133 million cubic meters to be
moved will be dredged. Hopper
dredgers are planned to remove about
7 million cubic meters of silt and rock;
cutter dredgers almost 33 million cubic
meters of gravel, clay through hard
rock, while 10 million cubic meters of
drilled and blasted material will be
loaded by dipper and backhoe dredgers
into barges.
Deepening of the entrance channels
outside the locks has already started.
Over the last year the TSHD BARENT
ZANEN (Royal Boskalis Westminster)
has been working on the Pacific side
and on the Atlantic side the heavy duty
cutter suction dredger J.F.J. DE NUL has
been active. Both dredgers were built
by IHC.
Inside the locks, in the canal the
Panama Canal Authority is doing the
dredging itself and it presently operates
its dipper CHRISTENSEN, the cutter
suction dredge MINDI and drill barges
THOR and BARU for drilling and blasting
rock mainly in the Gaillard cut,
supported by barges and tugs for the
transport of the excavated material.
The ACP is seeking to improve this
capability.
The 3.2 million Panamanians have
approved of the expenditure for the
Canal, but the Canal will not just be
expanded, a new port on the Pacific
side is to be created as well, as
Panama’s free trade zone is booming.
Panama City continues to grow at a
rapid pace.
Panama is on its way to becoming a
bustling center of trade for Central and
South America.
The Panama Canal Authority’s Master
plan is aiming for the widened Canal to
be completed by 2014, as this is the
year in which the Canal will celebrate its
100th Anniversary.
The CSD MINDI with spudcarrier pontoon was built in 1942 and is still working hard
The drill barge THOR drills into the rock, inserts explosive and blasts rock
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Navigational channel and locks excavation volumes
In million cubic meters (MCM)
1 Deepening and widening of the Atlantic entrance channel = 7MCM
2 New approach channel for the Atlantic Post-Panamax locks = 9MCM
3 Atlantic Post-Panamax locks with 3 water saving basins per lock chamber = 18MCM
4 Raise the maximum Gatun lake operating water level = 16MCM
5 Widening and deepening of the navigational channel of the Gatun lake and the Culebra cut = 5.5MCM
6 New approach channel for the Pacific Post-Panamax locks = 53MCM
7 Pacific Post-Panamax locks with 3 water saving basins per lock chamber = 14MCM
8 Deepening and widening of the Pacific entrance channel= 6MCM
Total excavation = 128.5MCM
(original 1914 construction = 205MCM)
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