Span Would Link Sicily to Mainland : Italy Planning Massive Bridge

Down through the centuries, the Strait of Messina has been an unbridgeable barrier of literally Homeric proportions, but now it seems that the celebrated strait may be spanned by the end of this century.

One of the experts involved in the planning says that bridging the strait would be an engineering endeavor that would make tunneling under the English Channel seem as easy as digging a hole.

A timetable adopted by the government of Italian Prime Minister Bettino Craxi in January calls for construction to begin soon on one of two proposed bridges, both of which call for the most massive engineering feat in the Mediterranean region since the Suez Canal was dug in the 1860s.

The idea of building a permanent link across the strait between Sicily and the mainland Italian region of Calabria has been the stuff of dreams, legend and frustrated hopes for thousands of years.

Among others who fought the treacherous strait, Homer’s hero, Odysseus, almost ended his Odyssey against the all-too-real hazards of Scylla, a rock near the Calabrian side of the strait, and Charybdis, the whirlpool on the Messina side.

Moving His Elephants

Hannibal is said to have planned a pontoon bridge across the strait so he could move his elephants from Carthage by the southern route, instead of across the Alps, en route to his invasion of Italy.

Napoleon, too, wanted to span the strait, as did Garibaldi, the hero of Italian unification in the 19th Century.

In 1870, a respected engineer named Carlo Navone actually designed a feasible railroad tunnel under the strait, but it was dismissed as wasteful when critics asked, “Why spend all that money for a few cases of Sicilian oranges?”

Engineers say it is just as well that Navone’s project never got under way, because it would have been like building a tunnel through the San Andreas fault. The Strait of Messina is situated in one of the most earthquake-prone areas on Earth. In 1908, a devastating quake--its epicenter centered almost exactly between Scylla and Charybdis--destroyed 90% of Messina, killed 84,000 of its 120,000 people and raised a 20-foot tidal wave that wiped out parts of the Calabrian coast and caused damage as far away as Malta. Neither a bridge nor a tunnel would have fared well.

Today the technology of bridge building has advanced to the point that a permanent span across the strait not only makes sense but is overdue, according to officials and experts.

“The Bridge of Messina should have been done 10 years ago,” said Carlo Lotti, one of the country’s leading technical and financial consultants. “A work of this kind is a calling card.”

Craxi’s minister of transport, Claudio Signorile, said, “We have a civil and an economic obligation to build it.” He predicted that the next 10 years will see “an estimated traffic increase across the strait of 45%” over that of the present old-fashioned ferries.

Final Studies Due

Signorile and other members of the ministerial commission on the bridge will receive final feasibility studies on two competing designs this month and decide later this year which to accept, with an eye to breaking ground for the new span by 1988.

Whichever they choose, it will be an extraordinary undertaking, stretching bridge technology far beyond all present limits, according to the engineers and businessmen involved in the rival projects.

Of the two plans, the most unusual calls for a bridge that would be virtually invisible, and for this reason it has won strong support from environmentalists.

This proposed span is called an Archimedes bridge by its designer, British engineer Alan Grant, because it relies on the same principle of buoyancy that prompted the ancient mathematician to leap from his bath crying, “Eureka!” (I have found it!) when he discovered specific gravity.

“It isn’t really a tunnel, so we don’t call it that,” Grant said. “We call it a bridge, and Archimedes is particularly appropriate for a bridge in Sicily because he came from Syracuse, then a Greek city on the island.”

Like a Submarine

Grant described the Archimedes bridge as a massive, buoyant concrete tube floating like a submarine about 100 feet beneath the surface of the strait, held in place by a network of steel anchor cables. The tube, cast in sections and towed into place by tugs, would enclose two highways and two rail lines, Grant said.

The strait’s notoriously fickle and strong (8-knot) currents would not cause the bridge to snake around under water, Grant said, because the anchoring system and the tube’s elasticity would prevent bending of more than a few feet over its entire length of 3.5 miles.

“In contrast,” he said, “a long conventional suspension bridge above the surface will move up and down as much as 18 or 20 feet under normal traffic.”

Grant’s chief financial backer, Elio Matacena, a Calabrian ferry fleet owner, held a drawing of the cable-anchored floating tube upside down to illustrate that “what we have, in effect, is an upside-down, underwater suspension bridge which, because of its buoyancy, undergoes much less strain than a massive steel suspension bridge hanging above the surface.”

Another advantage of the submerged bridge, Grant’s people said, is that there are no theoretical limits to its length, so it can be placed almost anywhere in the 19-mile-long strait, which varies in width from just under two miles at its northern end to about 8 1/2 miles at its southern end. The suspension bridge, on the other hand, must go at the narrow end so that it can be as short as possible.

‘Ride the Punches’

In an earthquake--and seismologists at the University of Palermo say a big one is surely coming one of these days--Grant and Matacena said, the Archimedes span should prove more resistant than a suspension bridge. “It will ride the punches,” Grant said.

Competing engineers behind the conventional but unprecedented-in-length suspension bridge design insist that their two-mile-long span would withstand earthquakes that register above 9 on the Richter scale, “and even a nuclear explosion at 500 meters distance,” according to the Rome newspaper Il Tempo.

“The pylons at either end of the suspension will rise higher than the Eiffel tower, as high as the Empire State Building (1,250 feet),” said Sen. Oscar Ando, a former mayor of Messina who has been chairman of the largely government-owned company behind the suspension bridge project since 1970.

Record Length

In length, the suspension design by Sergio Musmeci would dwarf such spans as the Verrazano in New York (4,260 feet) and the Humber Bridge in Britain, which at 4,626 feet is the world’s longest.

The length of the proposed span over the Strait of Messina, which Ando and other bridge proponents boast about, appears to have aroused as much criticism as support among technical skeptics and environmentalists.

If the financial and technical challenges of the two proposals are close, said Giuseppe Galasso, an undersecretary in the Ministry of Culture, “wouldn’t it be worth favoring the tunnel (the underwater bridge) rather than the bridge?”

And he went on: “The traffic advantages would be equal, but the countryside and environment would lose nothing and the historic and natural physiognomy would be preserved, as would this mythological and literary piece of land which does not deserve being liquidated so heartlessly.”

Engineers, understandably including rival bridge designer Grant, also balk at the great length of the bridge, more than double that of any previous single span, because they say it is doubtful that it could carry the railroad lines that are essential if the bridge is to succeed.

Unequal Weight Spread

“It’s crazy,” Grant said. “No suspension bridge of any great size takes rail traffic,” which, he said, applies too much weight unequally to the structure.

Rocco Di Ruggiero, an Italian-American who serves as deputy chief engineer of New York City’s river-spanning bridges, agreed that rail traffic over such a long span would present unprecedented problems.

“I don’t know of too many suspension bridges with railroads on them,” he said, other than the comparatively short East River bridges that carry New York City subway tracks. In a telephone interview, he noted that the center span of the Manhattan Bridge drops about four inches every time a subway train passes over. “It makes for structural and maintenance problems,” he said.

The head of Italian State Railways, Lodovico Ligato, said he tends to favor the suspension bridge because rail traffic is slowed too much by being spiraled down into a tunnel, even a floating one like the Archimedes bridge. But, he said, “We want a guarantee” that the suspension bridge would actually support rail traffic--”or our reply to the project will be negative.”

High Winds Cited

Fears have been raised, too, that high winds through the strait could endanger a bridge suspended over so long a distance 250 feet above the surface.

On this score, Gianfranco Gilardini, managing director of the Strait of Messina Co., which backs the bridge, said: “The wind exceeds 65 m.p.h. only eight hours a year, and we are assured of safe traffic for both trains and vehicles with winds up to 75 m.p.h. With a wind of only 50 m.p.h., you have to stop the ferries.”

Even if the winds become strong enough to stop traffic, they will not harm the bridge, according to two professors at the Polytechnic Institute of Milan. The two specialists made a miniature of the Musmeci suspension bridge and successfully tested it in the wind tunnel of the Fiat company at more than 150 m.p.h.

Calabrians generally have been less enthusiastic about the proposed link with Sicily than most other Italians, possibly because they have been on the losing end of state projects in the past.

Bid to Lift Economy

In the early 1970s, as part of a massive Italian effort to lift the economy of the southern part of the country, a huge saline chemical plant and the largest deep water port in the Mediterranean were built at Gioia Tauro, just north of the Strait of Messina, only to be abandoned unused, with no economic benefit to the poorest of Italian regions.

There are fears as well that most of the money spent to build the span--an estimated $3 billion for the suspension bridge, $1.5 billion for the Archimedes bridge--will wind up in the hands of outsiders.

Echoing local complaints that small Calabrian companies had been all but cut out of the planning phase, the region’s principal newspaper said they would find it virtually impossible to organize rapidly enough to get in on the bidding when a go-ahead decision is made.

“It will be like asking a consortium of country doctors to carry out a heart transplant,” grumbled Nino Calarco, editor of Gazzetta del Sud.