- Morandi Bridge in Genoa had needed several rounds of maintenance work
- Bridge, built in 1967, collapsed during fierce storm, killing at least 35 people
- At the time of collapse, it was undergoing work to strengthen foundations
- Expert warned in 2016 maintenance more expensive than knocking it down
- Transport Minister Danilo Toninelli vowing those responsible would 'pay up'
The motorway bridge which collapsed in Genoa, Italy, killing at least 35 people had been the subject of a series of 'exorbitant' maintenance works and had been causing issues for decades, it has emerged.
Engineering experts had warned that it would have been more cost effective to knock the bridge down than to continue to repair the 'uneven' construction.
The Morandi Bridge, built in 1967, was a main thoroughfare connecting the A10 and A7 highways and had therefore been heavily trafficked for more than 50 years.
Tuesday morning was no different, and dozens of cars fell several hundred feet when a 260ft section of the concrete bridge collapsed shortly after 11.30am.
Transport and Infrastructure minister Danilo Toninelli called the incident 'an enormous tragedy', vowing that those responsible for the collapse would 'pay up'.
'The first information would seem to say that the maintenance had been carried out, but it can not be so. These tragedies can not happen in a civilized country like Italy.'
Despite its majestic design, the structure of the Morandi Bridge, using two types of reinforced concrete, had caused issues over the decades and required expensive maintenance.
In the early 1990s, the suspension cables along the bridge had to be replaced, and further restructuring work was carried out in 2016.
In 2016, Antonio Brencich, associate professor of civil engineering at the University of Genoa warned that the Morandi Bridge's maintenance costs 'are so exorbitant that it would be cheaper to build a new one'.
In the article, quoted by Il Tempo, Professor Brencich says issues with the bridge being uneven and 'semi-horizontal' had plagued the construction since the early 1980s.
In December 2016, Genoan newspaper Il Secolo XIX claimed maintenance of bridges in the area had been lacking funds because authorities 'preferred to allocate more funds to new works'.
The paper accused officials in the Liguria region of only making important restorations when issues with bridges had become obvious.
Ian Firth, a former president of The Institution of Structural Engineers said the Morandi Bridge's 'very unusual' design creates a 'stiff arrangement' between the supports which is not common in cable-stayed bridges.
Mr Firth added: 'It is too early to say what caused the tragic collapse, but as this reinforced and prestressed concrete bridge has been there for 50 years it is possible that corrosion of tendons or reinforcement may be a contributory factor.
'There are no obvious signs to say what specifically triggered the collapse at this time; the fact that there was reported to be a storm at the time may or may not be particularly relevant.'
The highway operator said today that work to shore up the foundation of the Morandi Bridge was being carried out at the time of the collapse, adding that the bridge was constantly monitored.
Tuesday's incident is the latest in a string of bridge collapses in Italy, a country prone to damage from seismic activity but where infrastructure generally is showing the effects of economic stagnation.
The Morandi Bridge, also known as the Polcevera viaduct, was named after the engineer who designed it - Riccardo Morandi.
Morandi, who died in 1989, specialised in working with reinforced and pre-stressed concrete to design a series of bridges in Italy, South America and Libya.
The bridge which carried his name took four years to complete and was opened to the public in 1967, with the then-President Giuseppe Saragat presiding over the inauguration ceremony.
The bridge over the Polcevera stream was 3,615ft long, 148ft high and its longest span stretched 690ft.
Another Morandi bridge in Venezuela, built to a similar design to the one in Genoa, partially collapsed in 1964 after being hit by an oil tanker, just two years after it finished.
The General Rafael Urdaneta Bridge, also known as the Lake Maracaibo Bridge, had been completed just two years earlier when a tanker steered into it - killing seven people.
The collapsed part of thee bridge was rebuilt eight months later and no major issues have been reported since. The CNR civil engineering society called for a 'Marshall Plan' to repair or replace tens of thousands of bridges in Italy that have surpassed their lifespans, having been built in the 1950s and 1960s with reinforced concrete.
The group said the bridges were built with the best-known technology of the time, but that their working lifespan is 50 years.
It added that in many cases, the cost to update and reinforce the bridges is more than it would cost to destroy and rebuild them.
The CNR called for a major program to replace most of the bridges with new ones that would have a lifespan of 100 years.
It cited previous collapses, including one in April 2017 in the northern province of Cuneo that crushed a carabinieri police car.
Fortunately, the officers and the driver they had pulled over in a traffic stop heard the creaking noise and got out of the way in time.
Another was an overpass in the northern city of Lecco that collapsed under exceptional weight, crushing a car and killing the driver.