THE ME-RC BRIDGE (Messina-Reggio Calabria) · last century, almost all the solutions were related...
Transcript of THE ME-RC BRIDGE (Messina-Reggio Calabria) · last century, almost all the solutions were related...
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THE ME-RC BRIDGE (Messina-Reggio Calabria)
Giovanni Saccà1
The Messina – Reggio Calabria bridge as integration solution for two
metropolitan cities
ABSTRACT
Numerous hypotheses and projects have been made to overcome the Strait of Messina, most of which are
located in the narrowest area or in correspondence of the "Sella dello Stretto" where the minimum
distance between the coast of the Italian peninsula and Sicily is reached (Scilla and Cariddi).
As is well known, unfortunately, the chosen solution of the 3,300 m single span bridge has never been
realized despite the fact that a special international tender has been carried out since the contract was
declared lapsed pursuant to Law 1158/71 and the Company Messina SpA has been placed in liquidation.
In the Document on Economics and Finance 2017 (DEF 2017) annexed "Infrastructures" of Italian
Government, as part of the priority railway interventions, it was envisaged that a "Feasibility Study" should
be prepared with a view to enhancing the possible options for both stable and non-permanent crossing the
Strait of Messina along the "Napoli-Palermo" corridor.
This intervention was also included in the attached DEF 2018 "Connecting Italy" for the Southern Region (or
“Mezzogiorno”), which states, inter alia, that for the crossing of the Strait a feasibility planning phase is
underway: "The options to be considered for the verification of feasibility of the connection, stable or not
stable, through the Strait of Messina, will refer alternately to the road, railway or maritime mode".
This article aims to contribute to the search for a solution to permanently cross the Strait of Messina, while
at the same time solving the problem of integration between the two metropolitan cities of the strait in a
single large city.
1 ing. Giovanni Saccà, dean of the CIFI Section of Verona - http://www.cifi.it/Ppresidi.asp
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Introduction
The idea of creating the ME-RC bridge originated from the examination of the “Sulafjorden road crossing
project” prepared in 2015 by RAMBOLL & SWECO for the Norwegian Public Roads Administration
(Statensvegvesen) as part of the project to adapt the E39 highway.
Among the 43 alternatives examined to overcome this strait, we considered the solution of creating a
2000m two-span suspension bridge with a fixed foundation along corridor 2 using GBS (Gravity Basic
Structure) technology (Fig. 1 and 2).
Fig. 1 – Alternatives considered to overcome the Sulafjorden 2
2 https://www.vegvesen.no/sok?query=Sulafjorden
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Fig. 2 – Corridors taken into consideration for the crossing of the Sulafjorden
The corridor 2 provides for the crossing of a stretch of sea 4100m wide and 450m deep.
In order to realize the central tower of the bridge, we considered the idea of constructing a Condeep
(Concrete Deep-Water Structure) consisting of 23 base cells, 4 of which designed to escape from the water
and support the steel tower, and 2 designed to increase the horizontal stiffness of the structure (Fig.3). The
base cells of the Condeep have a height of 56 m (Fig. 4).
The four main columns of the Condeep extend from the basic structure up to 30 m above the surface of the
water to support the tower. Between the four main columns and the base of the steel tower, in the form of
a double capital letter A, many transition elements have been designed (Fig.5). The steel tower above the
four main trees of the Sulafjorden bridge is about 245m high (Fig. 6, 7 and Tab.1).
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Fig. 3 - Bridge pylon designed with GBS technology 3
3 Youtube “Video animazione Statens vegvesen - E39 Sulafjorden K2” https://www.youtube.com/watch?v=7s2l7Uq_oZ4
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Fig. 4 – Schema realizzativo della struttura di base del Condeep
Fig. 5 - Elements of transition between the four columns of the GBS structure and the steel tower out of water
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Fig. 6 – Suspension bridge with two spans for crossing the Sulafjorden along corridor 2
Total length of the suspension bridge m 4000 Span length of the suspension bridge m 2000 Navigable height m 75 GBS column size m Di = 32.0 at the bottom of C = 18.4 at the top Total height GBS m m 480 (senza gonna) GBS base area m2 20 500 epth of the GBS skirt m 20 GBS concrete volume m3 338500 (407,000 water depths 450 m) Distance between the four GBS columns at the top m 64m x 110m
Height of the steel tower placed above to the four columns of the GBS structure m 245
Tab. 1 – Project data of the two-span suspension bridge with GBS foundations on the Sulafjorden
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Fig. 7 – Measurements of the steel tower of the 2000m two-span road bridge designed for crossing the Sulafjorden
along corridor 2
The GBS structures can be designed to resist not only at the vertical load of the bays, but also at the
horizontal thrusts due to wind, thrusts due to sea waves, possible earthquakes, naval impacts and impacts
against icebergs. Among the numerous calculations to be carried out, it is important that the proper period
of the GBS structure does not coincide with the wave period to avoid that the structure resonates. In the
case of the Sognefjord (Fig.8) the measured period of the waves is between 12 and 14 seconds. For this GBS
construction the self-oscillation period was calculated in 6.33 sec.
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Fig. 8 – Design of the two-span bridge for crossing the Sulafjorden along corridor 2
Condeep structures have been built since 1973 for the increasingly widespread offshore fixed platforms for
the extraction of large deposits of crude oil and natural gas (Fig.9). Normally, the vertical elements support
a platform, with machinery and spaces for the crew and given their distance from the coast must be
designed with safety criteria such as to constitute a safe place even in areas with seismic danger and very
high waves.
These structures are part of the Gravity-based Structures GBS category, i.e. support structures that support
and resist external stress by exploiting gravity. A Condeep structure generally consists of a reinforced
concrete base for the storage of oil or gas from which then rise, for about 30 m above the mean sea level,
three or four "pylons" (towers) of reinforced concrete containing ballast and machinery like drilling
machines.
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Fig. 9 - Concrete platforms installed by Norway in the Atlantic Ocean Source: (www.olavolsen.no)
To date, the largest Condeep structures built are the 610 m high Petronius Platform and the 472m high
Troll for whose stability 35 m deep foundations have been built at the bottom of the sea.
Currently, these structures have been built up to a depth of 300 m and with the progress of construction
techniques such constructions are considered possible up to a depth of 500m. In the case of the bridge over
the Sulafjord, the depth of the sea at the point chosen for the construction of the Condeep pylon is 450m,
so that the overall height of the structure (Condeep plus steel tower) is about 720 m (Fig.8).
The Messina Strait bridge
Numerous hypotheses and projects have been made to overcome the Strait of Messina, most of which are
located in the narrowest area or in correspondence of the "Sella dello Stretto" where the minimum
distance between the coast of the Italian peninsula and Sicily is reached.
Taking into consideration only the hypotheses analyzed for the Strait of Messina since the eighties of the
last century, almost all the solutions were related to bridges with one or more spans (Fig. 10).
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Fig. 10 – Location of the bridges for the permanent crossing of the Strait hypothesized by the Strait of Messina Company S.p.A.
(SdM).
In Figure 9, the solutions with several spans discarded from the first phase of study are indicated in black.
The points placed in the middle of the sea indicate the position of the pylons that had been identified in
places where the sea was deep at most up to 145m. Lastly, the two solutions indicated with the color red
remained. Among these it was chosen that without a pillar placed in the middle of the sea to avoid the
danger of collisions of ships, because in this area the sea currents in some moments can be particularly
swirling and fast. As is known, the bridge chosen was that of a single span of about 3,300 m (red line
highlighted with the words "FINAL ALIGNEMENT" of Fig.10).
In the same area the hypothesis of creating a bored tunnel had been considered (Fig. 11).
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Fig. 11 – Location of the road and railway bored tunnels taken into consideration by the SdM.
This solution was judged achievable at the "Sella dello Stretto" at a depth of more than 150-170 meters
below sea level. But it was rejected for a whole series of reasons listed in the book "The Messina Strait
Bridge" edition of CRC PRESS and the Strait of Messina "2010:
“In summary, while bored tunnels in the Strait are certainly feasible, their principal drawbacks are: - Difficult boring conditions at the depths required in the specific geotechnical conditions; - Uncertainties in costs and technical Solutions for the advancement through the fault areas; - Extremely high construction costs, evaluated to be several times higher than for any bridge scheme; - All the negative functional aspects of very long tunnels with free road traffic connected with exhaust gas handling; - The risks connected with accidents-terrorism-sabotage within the enclosed tunnel body, for a piece of infrastructure that would possibly become an internationally sensitive target. Hence such schemes were not selected for further consideration. It is worth noting that no party has ever seriously supported bored tunnel options in the recent history of the Solutions proposed for the Crossing. Similar arguments, with certain due differences, also apply for immersed tube tunnels resting on the seabed and artificial dams supported on the seabed”. The same book mentions the reasons why floating tunnel alternatives were discarded:
“The floating tunnel alternatives proposed on and since the 1969 can be classified into two types:
Tunnels supported by piers, with buoyancy forces nearly balanced by ballasting, hence in a nearly
hydrostatically "neutral" condition.
Tunnels anchored by cable Systems to the sea bed, with buoyancy forces larger than the ballasting
so as to keep the anchor cables tight in Service".
Among the various proposals of this type, “Possible locations exist further south, with a shore to shore
distance of about 6 km and a sea depth of about 300 meters. The larger length implies higher costs,
although this is partly balanced by the more direct connection between the main towns of Messina in Sicily
and Reggio Calabria on the mainland” (Fig.12).
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Fig. 12 – location of the road and railway floating tunnels taken into consideration by the SdM.
After a long explanation on the reasons for which all the solutions of this type have been rejected, the
analysis, reported in the aforementioned book of the SdM, concludes: "These Solutions were thus discarded
after careful consideration, and it is indeed surprising to still find some supporters for such an application in
the Messina Strait”.
As is well known, unfortunately, the chosen solution of the 3,300 m single span bridge has never been
realized despite the fact that a special international tender has been carried out since the contract was
declared lapsed pursuant to Law 1158/71 and the Company Messina SpA has been placed in liquidation.
In the DEF 2017 annexed "Infrastructures"4, as part of the priority railway interventions, it was envisaged
that a "Feasibility Study" should be prepared with a view to enhancing the possible options for both stable
and non-permanent crossing the Strait of Messina along the "Napoli-Palermo" corridor.
This intervention was also included in the attached DEF 2018 "Connecting Italy" for the Southern Region (or
“Mezzogiorno”)5, which states, inter alia, that for the crossing of the Strait a feasibility planning phase is
underway: "The options to be considered for the verification of feasibility of the connection, stable or not
stable, through the Strait of Messina, will refer alternately to the road, railway or maritime mode".
4 http://www.mit.gov.it/sites/default/files/media/notizia/2017-04/Allegato_MIT_AL_DEF_2017.pdf 5 http://www.mit.gov.it/sites/default/files/media/notizia/2018-05/Allegato_3%20bis_-_Connettere_lxItalia.pdf
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The ME-RC bridge (Messina-Reggio Calabria)
Examining the depth of the Strait of Messina, using GBS technologies, we can observe that it is possible to
build bridges similar to those designed on the Sognefjord along several corridors.
Among the many possibilities, I have taken into consideration the one able to reduce to a minimum the
times of connection between the metropolitan cities of Messina and Reggio Calabria in order to maximize
their use and usefulness for the local populations, which should be the main users of this work.
The bridge must eliminate, as far as possible, the current obstacle both economic and temporal, which
prevents the development of the metropolitan area of the Strait and more generally of Sicily and Calabria.
In the specific case of the ME-RC bridge, located between Messina Scalo and Villa San Giovanni Scalo, it is
necessary to cross a stretch of sea at a maximum depth of 320 m. The two central pylons should be built in
an almost flat area called "Messina Valley" in places 300 m deep, which are much less than 450 m of the
Norwegian Sulafjord. The distance between the coasts along the chosen route is 6.620m (Fig.13).
Fig. 13 - Location of the ME-RC bridge in the Strait of Messina
Given that the bridge over the road must also be railway and that currently there is no bridge of this type in
the world with a span of more than 1,408 m, to overcome the distance of 6,620 m should build a
suspension-type hybrid bridge consisting of 5 spans of 1,324 m using 4 GBS pylons. The current road and
rail bridge record, which has a span of 1,408 m, is held by the Yavuz Sultan Selim bridge, the "third bridge
over the Bosphorus", inaugurated on 26 August 2016.
Given the depth of the sea along the chosen route, we should build 4 condeep + tower of heights between
400 and 500 m. It should be noted that the large spaces present at the four Towers + Condeep would allow
the construction of both tourist sights, commercially exploitable, and safe places to be used in case of
emergency (Fig. 14).
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Fig. 14 – The ME-RC Bridge (https://www.youtube.com/watch?v=mlhXQmVIWso&t=1s)6
Due to the required positioning of the new station of Messina Centrale at the current Messina Scalo, it will
be necessary to make navigable for large ships the fourth bay on the Sicily side, so that the slope is about
17 ‰, which is less than the maximum allowed on the network Italian AV / AC (18 ‰) (Fig. 15).
Fig. 15 – Maximum estimate of the main dimensions of the ME-RC bridge
6 Youtube “Ponte ME-RC & TPL dello Stretto di Messina” https://www.youtube.com/channel/UC8U8GZs3SV877_kJ9Y4Nk3Q&t=1s
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On the ME-RC bridge, in addition to the double-track railway line, a three-lane highway could also be built
for each direction in order to cope not only with long-distance traffic but also with the future of the
metropolitan city of the Strait. Given the short distance between the two cities of the Strait we could
imagine of also activating a metropolitan railway suburban service between the two coasts in order to
connect very quickly through the bridge over the center of the two cities also all the locations between
Rosarno and Melito of Porto Salvo in Calabria and all the localities included between Giampilieri and
Barcellona Pozzo di Gotto in Sicily. The fast regional trains could connect the main Sicilian cities with the
main cities of Calabria, the long-distance passenger trains AV could connect the Sicilian cities with the main
national cities and the goods trains AC ports and Sicilian interports with the main national interports. All
this will create the conditions to revive the economy of the enlarged area of the Strait by simplifying the
movements of people who could move daily between their homes and points of interest of the other city,
the ZES annexed to the Port of Gioia Tauro, the airport of the Strait "Tito Minniti", to the tourist and
productive areas / ZES of Milazzo / Barcelona and Giampilieri / Taormina, Catania, etc.
In the immediate vicinity of the pylon located on the Sicilian coast, there could be a highway junction
connected to the central viale Europa (Fig.16).
The highway, from the ME-RC bridge, would continue in viaduct following the old route of the former
Messina-Palermo railway in a superelevated way, to allow the use of the old railway line as an underground
line.
Fig. 16 – Highway junction “Messina Europa”
The Angel's gallery would be used for the subway, while the highway tunnel would be built on. Immediately
after, in via del Santo viaduct, the motorway would continue in the tunnel until the E45 where the Messina
Ponte junction would be realized between the junctions of Messina Center and Messina Gazzi (Fig.17, 18).
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Fig. 17 – Motorway tracks to which was added the junction between the ME-RC bridge the E45 and current
motorway junctions to which were added "Messina Europa" immediately after the pylon and "Messina
Ponte" between the "Messina Gazzi" and "Messina Centro"
Fig. 18 – Map of Messina with highlighted in white the area of the new station of Messina Centrale (Maregrosso), in brown the new highway from the bridge ME-RC to the E45 and the new junctions of "Messina Europe" and "Messina
Bridge", in green the route of the former Messina-Palermo railway (Camaro-Messina Scalo route) is highlighted
The new Messina Centrale station should be built in Maregrosso (Fig.19), currently used as Messina Scalo,
in the same area already identified until 2005 for the construction of the "Messina Ponte sulla Stretto"
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station. From the new railway station, following the coast, using the railway line you reach Catania, while
using the Peloritani base tunnel you reach Palermo.
Fig. 19 – Location of the new central station of Messina
Among other things, the new railway station of Messina Centrale, being of transit or not more than head,
will no longer have the need to have nearby locomotive deposits and airports where to park rolling stock
travelers and goods. The regional and metropolitan trains could use the railway systems of Reggio Calabria,
freeing up ample space in Messina. The area of the former Officina Grandi Riparazioni of Messina could be
reused for the storage and maintenance of rolling stock of the metropolitan lines.
After completing the coverage of the San Filippo stream, the square of the station of Contesse and the
connecting tracks with the Tremestieri stop could be transformed into an intermodal center where to load
and unload from the commercial means that otherwise would travel the Italian motorway network for
hundreds of kilometers.
The area between Gazzi and the Falcata Area will become central and valuable, therefore it will be
necessary to prepare a special urban study to be included in the General Town Plan of the city of Messina
to cope with the design of hotels, commercial and residential spaces, structures accommodation and
conference, streets and squares, areas for multi-story parking.
With the construction of the ME-RC Bridge it will be necessary to redesign the city water front visible from
the bridge and the areas crossed by the new highway link must be adequately redeveloped as they will
become an integral part of the new city center, as well as Messina's business card Sicily and positive symbol
of the whole Italy.
The ME-RC Bridge project will make commercially attractive many areas included in the "CAPACITY" project
as areas to be redeveloped. In particular, the following territorial areas will be affected by the collateral
works at the ME-RC bridge: Gazzi, Fondo Saccà, Camaro, Zona Falcata, Fondo Fucile and Villaggio Santo.
Therefore, the construction of the ME-RC bridge is not only important for crossing the Strait, but also for
the rehabilitation of the city of Messina, which since being hit by the earthquake of 28 December 1908
continues to suffer from problems related to emergency housing of thousands of people.
In light of this, the construction of the ME-RC Bridge represents a reversal of the terms as it transforms
urban redevelopment interventions into a strategic investment of international importance that
permanently modifies the value of the areas involved.
Simultaneously with the construction of the ME-RC bridge it would be necessary to rethink the TPL both in
Messina and Reggio to significantly reduce road traffic congestion and to boost the economy by simplifying
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the movement of people (integrated single ticket of the new metropolitan city of the Strait usable on all
public transport).
The former route of the Messina-Palermo railway, between Camaro and Messina Scalo (about 7 km), could
easily be transformed into a subway (green line) which, after reaching the new station of Messina Centrale,
could continue via the bridge to the city of Reggio Calabria.
Moreover, it would be advisable to build a new metro line in Messina from Tremestieri Porto to the
Annunziata (red line about 11 km long) in order to drastically reduce road traffic congestion and quickly
serve all the most urbanized areas of the city and in particular the historic center, the main schools, offices
and shopping centers (Fig. 20).
It should be remembered that according to the periodic reports "TomTom index" both the city of Messina
and that of Reggio Calabria are normally classified at the national level between the 2nd and 4th place for
road traffic congestion and it is for this reason that from the DEF 2016 there are plans to upgrade
metropolitan and tram services in the two cities (SdF, PUMS, etc.)7.
Along the route of the new red metro line "Tremestieri-Annunziata" a branch should be provided at Villa
Dante in order to serve the new central station and then, through the ME-RC bridge, quickly reach Calabria.
The realization of this new metropolitan line is very important to eliminate the current bottlenecks and to
improve the quality of life of citizens.
7 Giovanni Saccà - "Integrated local public transport system between metropolitan mobility and the permanent connection of the Strait of Messina" - "INGEGNERIA FERROVIARIA" magazine ed. C.I.F.I. n.2 / 2018 - pag.95-121.
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Fig. 20 – Traces of the hypothesized metropolitan lines, tramways and cableways of Messina
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The route has been chosen so as to be sufficiently far from the sea and at the same time to maintain its
centrality, while at the same time avoiding being a hindrance to commercial activities. Underground stops
should be available in spaces already available or easily available as a result of limited expropriation.
In this context the current tramway line (yellow line) would change the route from Villa Dante to the new
station of Messina Centrale as it would no longer be necessary to reach the current southern terminus at
the ZIR, already served by the new red metro line through the Policlinico stop and the Messina Fiumara
Gazzi train stop.
On this occasion, it will be possible to modify the route of the current tramway also in the central area in
order to significantly increase the commercial speed. In particular, when reaching the current railway
station in Piazza della Repubblica, you could continue straight to the port and make a stop at the docking of
fast ships. Then, rectifying the boundary of the port area, the route could be moved to the Municipio stop
in order to eliminate the current problems connected with the commercial activities along the port. From
the Municipio stop the tram could continue according to the current route up to the terminus of the
Museum or it could continue until the Annunziata in order to find correspondence with the metropolitan
line.
The new metro line would cross the city along its entire length, while the tramway line would serve as
reinforcement for the central areas, being able to also serve the port areas difficult to reach by
underground. Connections with the valleys and hilly districts should continue to be carried out by bus.
To enhance the cultural and tourist nature of the city of Messina, as well as to connect the tramway and
the two metropolitan lines, in order to minimize urban travel time, it would be advisable to build an urban
cable car (white line) from Boccetta, where they moor the cruise ships, to fort Gonzaga reachable in about
10 minutes and from where you can admire the beautiful panorama of the Strait of Messina, declared by
UNESCO heritage of humanity (Fig. 21).
The urban cable car (white line) interconnects centrally with the tramway (yellow) at the "Boccetta" stop
(Fig.20), with the red metro line at the "San Francesco" stop, with the green metro line at the the stop
"Montepiselli / Bisconte" before reaching the terminus "Gonzaga". All this will contribute decisively to its
continuous use as it significantly reduces urban travel time and at the same time could become an
attraction for cruise passengers and more generally for tourists.
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Fig.21 – Panorama of the Strait and ME-RC Bridge seen from Fort Gonzaga
Moving on the Calabrian coast, we can analyze the effects that will have on the Public Transport of the
Metropolitan City of Reggio Calabria following the construction of the ME-RC bridge.
The motorway and rail connections in Calabria do not foresee significant changes and therefore are very
simple to carry out. In particular, for the motorway part it is necessary to build a connecting viaduct
between the Calabrian tower of the ME-RC bridge and the Mediterranean motorway, about 1 km long and
a new highway junction immediately after the exit for Villa San Giovanni (Fig. 22).
As far as the railway is concerned, it is necessary to connect the bridge with the existing railway in order to
continue both towards the station of Villa San Giovanni and then towards the north, and towards Reggio
Calabria and beyond. The metropolitan service coming from the bridge, continuing towards Reggio
Calabria, could use the current railway stations and stops (Fig.23).
Immediately after the Pentimele stop, we could imagine a junction from which to derive a passing
metropolitan railway line, which would pass through the city center until you reach the "Tito Minniti" Strait
airport and the S. Gregorio station where you could reconnect to the current railway line (Fig.24). In this
way fast metroferrovia services could be activated between the two metropolitan cities of the Strait. Also
this route, as well as the new metropolitan line hypothesized in Messina, would serve the historic center,
the main schools, offices and shopping centers.
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Fig. 22 – highway junction “Reggio Calabria Ponte ME-RC”
Fig. 23 – Lines and railway connections of the ME-RC Bridge (the radius of curvature of the railway lines at the two ends of the bridge is about 500m which will limit the maximum speed to about 105 km / h)
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Fig. 24 – Trace of the hypothesized metropolitan railway line passing through Reggio Calabria
The combination of all these project proposals could become, in the following years, a source of development for the revival of the Strait and Southern areas. By influencing the brownfields and redeveloping the waterfront of the two coasts, the economic, social and cultural reality of the entire metropolitan area will be boosted.
In conclusion, let us remember that the Scandinavian-Mediterranean corridor, one of the four TEN-T corridors that cross Italy, in its final part from Naples to Palermo must necessarily cross the Strait.
The TEN-T networks (Trans-European Networks - Transport) are a set of integrated transport infrastructures, provided by the European Community to support the single market, guarantee the free movement of goods and people and strengthen growth, employment and the competitiveness of the European Union. Today the priority at European level is to ensure the continuity of the corridors, creating the missing connections, ensuring connections between the different modes of transport, eliminating the existing bottlenecks. In this specific case, the realization of the stable crossing would eliminate the insularity of Sicily. As mentioned in the Maastricht Treaty of 7 February 1992, the TEN-T networks aim to facilitate the interconnection of national infrastructure networks and their interoperability, taking into account in particular the need to link island regions without the central regions of the Union. outlets to the sea and peripheral.
Trusting in the happy and timely conclusion of both the Feasibility Study phase of the Strait crossing, foreseen by the DEF 2017 and the DEF 2018, that of the consequent preparation of the General Regulatory Plan that includes both the regulation of the construction of the new water front and the redevelopment of the areas crossed by the new railway and road routes, and the reorganization of the TPL of the Metropolitan Area of the Strait, we can conclude that the hypothesized interventions will allow a drastic reduction of travel time between the most populous districts of the two cities, significantly reducing the need to use private cars, contributing in a decisive way to make the metropolitan cities of Messina and Reggio Calabria recover many positions in the classification of livability between the cities of Italy and Europe as well as contributing decisively to the social and economic revival of a significant part of Southern Italy. Considering that overall the two metropolitan cities have a population of approximately 885,000, the number of passengers / days that will benefit from the public service should be on values such as to justify the investment, as it usually happens in all European metropolitan cities of equal dimensions. We must not forget that the union of the two metropolitan cities would give life to a city that will be the 7th city of Italy and the 3rd of southern Italy.
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NOTE
This idea of stable crossing of the Strait of Messina was presented by Ing. Giovanni Saccà during the
conference held at the Municipality of Messina in the Hall of Flags on February 23, 2019 of which the
program is attached (Fig. 25), some photos and the article appeared in the Gazzetta del Sud on February 24,
2019 on page. 25 and on internet at address: http://www.experiences.it/archives/15105 .
Fig. 25 - Conference program
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