Genoa: the worksite that won’t stop for Coronavirus

Giving the city back its bridge

Massimiliano has lived in Certosa his entire life. “When we were kids, we used to play football with our friends on the hill at the end of Via Mansueto,” he recalled. “From there the view overlooked the Brooklyn Bridge.”

That’s what people in the neighbourhood called the Morandi because its high piers made it look like New York City’s iconic bridge. 

“Today we watch the new bridge go up and experience the construction in real time,” he said. “I see the piers, the deck. I am impatient to see it finished, like everyone else in this neighbourhood.”

The Certosa residents have followed every moment of that construction, every change, every important step — often marked by the sound of the construction site siren.

It was 3:51 PM on June 25, 2019 when the siren sounded to inform everyone that the concrete had started being poured into the foundations of the bridge. Salini Impregilo CEO Pietro Salini called the first casting “a milestone in a strategic project for Genoa and the whole country.”

Only a few days after, on July 1, Certosa had bid farewell to its Brooklyn bridge. New siren, new event: the spectacular demolition of Piers 10 and 11, the Morandi’s last remaining piers.

Since then, work has continued at an intense pace, seven days a week, twenty-four hours a day. The only stop for a break was at Christmas, as Salini Impregilo promised when it was chosen to build the new bridge on December 18, 2018.

Now that promise is being kept. While the city is admiring the valley’s new skyline, the “dressing” work on the bridge is proceeding. This work is more difficult to see, because it takes place inside the scaffolding of the decks and creates what many people call “an invisible city.”

The city hidden inside the new bridge

Forty metres (131 feet) high above the Polcevera River valley, at the top of the 18 cement piers that support the bridge, workers are toiling incessantly to put the finishing touches on the technological soul of the new viaduct, an “invisible city” taking shape from one day to the next. Hidden inside the bridge’s deck sidings are rainwater disposal and treatment features, air dehumidification, sensors that monitor the tightness of the structure and robots in charge of maintenance.

Francesco Poma, project director of PerGenova, explained how this works.

“All of this is going on inside the deck’s sidings,” said Poma, a long-time engineer with Salini Impregilo, and veteran of such projects as Italy’s high-speed rail line and the Salerno-Reggio Calabria motorway. “This decision was not by chance. Architect Renzo Piano wanted to hide all the management systems in order to provide Genoa and travelers with an infrastructure that was also unique for its beauty.”

For example, the water disposal system was designed to collect rainwater that is carried away by hidden pipelines instead of being discharged onto the piers, ruining their beauty. Once collected, the water is transported to two purification plants, located on the west and east side, and then sent to the Polcevera River after treatment.

Completing the “invisible city” is part of the “last mile” of this huge project. The bridge is crawling each day with hundreds of people coming up and down the piers and working on the deck. But it will also move, on its own.

The bridge that breathes

Genoa’s new bridge breathes, it moves. It is alive. That’s because its steel structure expands and contracts up to 80 centimetres (31 inches) in sync with temperature changes between winter and summer.

This natural phenomenon must be carefully managed to avoid damage to the structure from the deck’s expansion.

And so, in recent days, while section after section of the bridge’s span are positioned, tested and approved at high altitudes, workers on site are busy substituting the temporary supports with permanent ones, sphere-shaped structures that can weight up to 10 tonnes, which are positioned between the viaduct and the top of the piers, and make the entire structure more flexible. 

“In some situations, in order to reach our goal of completing the bridge in a shorter time, the design, construction and testing of the final supports was carried out at the same time we positioned the bridge sections on temporary supports,” said Poma. “That way we could speed up work up top, on the entire span. As a result, we are now replacing the temporary supports. This is a highly complex procedure that involves using two cranes to lift a platform suspended at a height of 40 metres (131 feet) and weighing 60 tonnes, designed to bear both the weight of the temporary and the permanent supports.”

This is a bridge that breathes. It shrinks with cold and expands with heat, and it is also able to withstand any seismic stress.

“Technological supports like these avoid creating loads on the piers and sidings of the deck when the bridge ‘breathes,’” said Poma. “This part of the design means the bridge can sit and breathe like a big motionless animal, while the city of Genoa comes and goes across its back.”

The “last mile” of a massive project

In addition to the positioning of the final supports, this “last mile” of the project takes place at a height of 40 metres (131 feet), in a race toward the finish line to deliver the work within the next few weeks. After months of round-the-clock toil that allowed the piers to be completed and the decks to be laid, now the work up on top must be finished. It will take another two months for the decks to be finished and for the reinforced concrete castings for the bridge slab to be prepared.

“To lay the reinforced concrete will take about ten days of work,” explains Stefano Mosconi, engineer at Salini Impregilo and Construction Manager at PerGenova. “This will allow us to build what we call the spine of the bridge, where the cars will drive.”

The work will continue seven days a week, 24 hours a day, until the laying of the asphalt is finished and the 22 lamps, each 28 metres (91 feet) high, will be hoisted to provide a spectacular illumination of the entire structure. All of this work will be carried out respecting the new safety rules that the construction site has put in place to cope with the coronavirus emergency.
“A whole series of new names have been coined to describe the methods we are using Genoa now: Fast Track approach, Genoa method, and so on,” said Nicola Meistro, Salini Impregilo’s engineer and CEO of PerGenova. “What I would like everybody to keep in mind, however, is that the construction sector in Italy has a long tradition covering generations of families (like mine), of achievements all over the world, but above all of great passion and skill. Only when passion and skill are combined can we achieve what we are doing in Genoa. Let’s show the world that the Fast Track approach and the Genoa method means we are able to build the infrastructure quickly and well that our country needs so much.” 

Work doesn’t stop for the virus 

In the narrow streets of Certosa, people walk around in masks. This part of Genoa was declared a “red zone” on August 14, 2018 because of the danger that other sections of the Morandi bridge could collapse. Now it is facing a new emergency, a worldwide emergency that has now transformed all of Italy into a huge “red zone.”

Residents are confined to their homes; you can only go out to take care of essential needs, but on Via Fillack the hustle and bustle of men and vehicles has never stopped. Genoa’s new bridge is a strategic infrastructure project for the entire country, and that’s why work has continued. At the worksite, the most stringent safety measures have been put in place to protect workers.

Body temperature is measured by thermo scanners at all entrances to the yard; hand disinfectant has been distributed to all; social distancing is followed to the letter, and of course the working environment and all common areas are frequently cleaned and sanitized. These measures allow work at the yard to continue.

Salini Impregilo has adopted this same policy of rigour at all its construction sites around the world, aware that the challenge for large companies carrying out strategic projects is twofold: on the one hand protecting the health of workers, and on the other ensuring work continues on strategic projects vital for the economy.

Therefore, work on the bridge goes on. Nearby residents watch the construction site from their windows, pausing every evening at sunset when a tricolour beam of light pierces the valley. This ethereal bridge punctuates the workers’ shifts, and pays homage to a city that has never stopped fighting.