PROJECT OVERVIEW
This
project if completed would stand as one of the Landmark Bridges of the
21st century. It would be the longest suspension bridge ever built
(between towers).
The
Strait of Messina (divides the island of Sicily from Calabria in
southern Italy) is 2 miles (3km) wide. While the overall length is not a
big problem the economics, water depth, wind, and earthquakes all have
to be accounted for.
Presently
all has been accounted for except the economics. To avoid the problem
of the deep water, the solution was to design the longest suspension
bridge ever. It will have a 3300 m (2 mi) main span and 180 m (590 ft)
side spans (overall length 3.7 km (2.5 mi)). The main piers will be
founded in 120 m (400 ft) of water. There will be a new patented lighter
deck design which deals with aerodynamic and seismic problems. The wind
will be no problem as the aerodynamic features of the bridge will allow
it to withstand 216 km/hr (134 mi/hr). Earthquakes will have to be huge
as the bridge will be able to face without damage a seismic action
corresponding to 7.1 magnitudes in Richter scale (severer than the
earthquake that destroyed in Messina on 1908). The only obstacle left is
the funding. The bridge is expected to cost five billion dollars and
take eleven years to build.
The
bridge will be 60 m (196 feet wide) and will have 12 lanes for traffic
and two lanes in the middle for trains. This will allow 140,000 vehicles
and 200 trains per day. This will cut down transit times of up to 12
hours down to minutes.
The
new Messina Straits suspension bridge to link Sicily with the Italian
mainland was likely to be one of the most impressive feats of
engineering undertaken this century and one of the biggest construction
projects ever undertaken in Europe.
Following
the plans for the bridge being scrapped by Italy’s new prime minister
in October 2006 the project was thought to be totally dead and buried.
However, governments change and in April 2008 a general election
returned the previous Prime Minister Silvio Berlusconi to power. One of
Berlusconi's first acts was to revive the bridge project.
Although
the project was welcomed and criticized in equal measure, it is certain
that it would have inspired a generation of Italians to marvel at their
country's engineering skills and prowess. The bridge would have
significantly helped reduce the infrastructural deficit in Southern
Italy, creating favorable conditions for the economic growth and social
regeneration of the region and promoting an integrated road
infrastructure (probably requiring badly needed additional investment).
The
bridge was being constructed by the Italian Government, which formed a
company, the Stretto di Messina SpA, to oversee construction and operate
the bridge when potentially completed in 2012.
Spanning
the Messina Straits, the bridge would have been almost 4km (2.5 miles)
long and would have cut the two-hour journey time by ferry and train
(transporting over 18,000 vehicles per day). The controversial project
had been on the drawing board since the 1960s and has been criticized
because it would be a waste of public money in Italy where public
spending is already overstretched and also because the area in which the
construction was taking place had some seismic activity in the past.
The
bridge would have cost an estimated €4.4bn ($5.3bn; £3bn) to build. The
bridge would have been the world's longest suspension bridge and was
expected to have a service life of 200 years.
PROJECT PLANNING
The
Strait of Messina Bridge preliminary project is a revised version of
the project first proposed in 1992, updated to include the recent
findings and resolutions of the Technical and Scientific Committee set
up by the Italian Ministry of Infrastructure.
This
Committee began work in February 2002, drafting the bridge design
guidelines. The Government's technical advisor during the design stage
is Steinman International. Stretto di Messina has also made further
technical improvements in environmental and urban planning issues.
In
May 2006, the bridge building project was questioned by the
newly-elected Italian Prime Minister, Romano Prodi, but the project
itself could not be scrapped at the time because of agreements and
contracts previously entered into by the former government mandating
either the construction of the bridge, or an equivalent penalty payment
to the contracted construction companies. As will be seen later, he did
not give up his questioning.
BRIDGE DESIGN
For
the design of a crossing structure, the preliminary project
definitively opted for a 3,300m-long single-span suspension bridge that
will have the world's longest central span. The deck was to be 3,666m
long, including the two suspension side spans, and 60m wide.
The
structure was to be composed of three box sections – two lateral ones
for the roadway deck and a central one for the railway tracks. The
deck's roadway section was to have three 3.75m-wide lanes in each
direction (two driving lanes and one emergency lane). The railway
section was to have two tracks and two lateral pedestrian sidewalks.
The
height of the two towers was set at 382.6m to allow for a navigation
clearance with a minimum height of 65m – in the presence of maximum load
conditions – and a 600m width; the height of the deck's anchoring on
the Sicilian side was lowered by 11m.
The
bridge's suspension system was to be secured by two pairs of steel
cables, each with a diameter of 1.24m and a total length between the
anchor blocks of 5,300m.
The
bridge was designed to resist, without damage, an earthquake of 7.1 on
the Richter scale – much more severe than that which devastated Messina
in 1908. It was also designed to withstand winds of more than 200km/h,
given its aerodynamic configuration.
CONNECTION TO ROAD SYSTEM
The
preliminary project included 20.3km of road links and 19.8km of railway
links to connect the bridge to the existing networks. Under the new
design, most of the links were to be developed in tunnels enabling
connection of the bridge directly to the new routes.
On
the mainland, the bridge was to connect to the new stretch of the
Salerno-Reggio Calabria highway (A3) and to the planned Naples-Reggio
Calabria high-speed railway line; on the Sicilian side, to the
Messina-Catania (A18) and Messina-Palermo (A20) highways as well as the
new Messina railway station (to be built by Rete Ferroviaria Italiana).
WIND PROBLEMS
The
Strait of Messina Bridge was to be open 365 days a year, 24 hours a
day, without any interruption to traffic due to strong winds. This was
due to its intrinsic stability and the use of special wind protection
barriers that will allow traffic to move normally even in the presence
of strong winds.
With
regard to stability, the bridge, defined as 'designed by the wind', had
a wing profile with aerodynamic characteristics that enabled it to
withstand winds at speeds of more than 216km/h (in over 20 years of wind
monitoring, speeds of more than 150km/h have never been reached).
Studies
in wind tunnels have made it possible to provide a comfortable crossing
and optimum stability in the presence of medium / low and strong winds.
SEISMIC ACTIVITY
Suspension
bridges are not typically sensitive to earthquakes as the bridge's
structural configuration has a type of natural insulation that comes
from the typical frequencies of seismic stresses (periods of fractions
of seconds). This helps to insulate the structure against the physical
possibilities of vibration periods of several seconds and tens of
seconds.
The
Strait of Messina Bridge was designed to withstand an extreme
earthquake with a magnitude of around 7.1 on the Richter scale (the
maximum ever recorded in Italy) with the focus at around 15km from the
bridge. Such an earthquake is extremely rare.
Key Data:
Start Year
|
1992 (designs have been on the board since 1960s)
|
Estimated Investment
|
€4.4bn
|
Completion
|
2012
|
Start
|
October 2006; Bridge scrapped by Italian parliamentary vote.
|
Central Span Length
|
3,300m
|
Total Length
|
3,666m
|
Suspended Deck Width
|
60.4m
|
Cables :
Number of main cables:
|
4
|
Diameter of each cable:
|
4.1 ft (1.24 m)
|
Length of each cable:
|
7,650 ft (2,332 m)
|
Number of wires in each cable:
|
41,148
|
Total weight of cables:
|
166,000 tones
|
Bridge Specifications:
Tower Height
|
382.6m, each containing 56,000t of structural steel
|
Suspension Cables
|
Two pairs, 5,300m long with a diameter of 1.24m – 44,352 wires for each cable
|
Minimum Central Navigable Clearance
|
65m high by 600m wide
|
Lanes
|
Six driving lanes, three for each direction (one fast, one normal, one emergency)
|
Service Lanes
|
Two
|
Rail Tracks
|
Two
|
Traffic Capacity
|
6,000 vehicles/hour and 200 trains/day
|
Key Players:
Sponsor
Stretto di Messina SpA, Italian Government
Main Contractors
Impregilo,
Ishikawajima-Harima Heavy Industries of Japan, Sacyr Vallehermoso of
Spain and Sacyr S.A., Società Italiana Per Condotte D'Acqua SpA,
Cooperativa Muratori & Cementisti-CMC and Parsons Transportation
Group
Other Contractors
Systra
SA, Bonifica SpA., Systra-Sotecni SpA, Ast Sistemi Srl. Fenice SpA,
Agriconsulting, Eurisko, Nautilus, Theolab, Istituto Nazionale della
Fauna Selvatica, Marsh SpA and PricewaterhouseCoopers.
Operator
Stretto di Messina SpA
Two satellite pictures of the strait of messina
Key Players:
Sponsor
|
Stretto di Messina SpA, Italian Government
| |
Main Contractors
|
Impregilo,
Ishikawajima-Harima Heavy Industries of Japan, Sacyr Vallehermoso of
Spain and Sacyr S.A., Società Italiana Per Condotte D'Acqua SpA,
Cooperativa Muratori & Cementisti-CMC and Parsons Transportation
Group
| |
Other Contractors
|
Systra
SA, Bonifica SpA., Systra-Sotecni SpA, Ast Sistemi Srl. Fenice SpA,
Agriconsulting, Eurisko, Nautilus, Theolab, Istituto Nazionale della
Fauna Selvatica, Marsh SpA and PricewaterhouseCoopers.
| |
Operator
|
Stretto di Messina SpA
|
Two satellite pictures of the strait of messina