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| 3D Satellite |
Aug 14, 2018: A motorway bridge has collapsed in the northwest Italian city of Genoa, killing 26 people and badly injuring 15, police told the BBC. (This article contains a video of during and after the collapse.) The final fatality count seems to be 43. 600 people were left homeless.
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The tower in the center of this view was the one that collapsed.
Another street view was taken after the collapse.
I wonder why they are taking down the approach viaduct as well.
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| Via BBC |
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| Scroll down in this article to find this video. |
"Already 8 years ago, voices were raised that the bridge would collapse within ten years, due to rust and other problems innate in the design - problems known by the architect since the bridge was constructed in the 60s." [CTIF] In fact, extra cables were added to the stays of Tower 11 in 1992. But nothing was done to Tower 9, which was the one that collapsed.
Morandi was one of the Italian engineers that were pioneering the use of pre-stressed concrete to replace steel in structures. Morandi thought that encasing the cable stays in pre-stressed concrete would prevent corrosion. But it didn't. But it did make it harder to inspect the cables. ("Indeed, an investigation into the bridge in 2017 was unable to determine if the reinforcement had corroded." [engineering.com]) The bridge was in such bad shape that the owner had decided in April 2018 to retrofit the bridge. But just four months later when the bridge collapsed, it became painfully obvious that the owners did too little too late. [TheGuardian]
Several articles mentioned that the cement industry was controlled by the Mafia and speculate that too much sand and/or water was used in the cement to cut costs and increase their profits.
Morandi was one of the Italian engineers that were pioneering the use of pre-stressed concrete to replace steel in structures. Morandi thought that encasing the cable stays in pre-stressed concrete would prevent corrosion. But it didn't. But it did make it harder to inspect the cables. ("Indeed, an investigation into the bridge in 2017 was unable to determine if the reinforcement had corroded." [engineering.com]) The bridge was in such bad shape that the owner had decided in April 2018 to retrofit the bridge. But just four months later when the bridge collapsed, it became painfully obvious that the owners did too little too late. [TheGuardian]
Several articles mentioned that the cement industry was controlled by the Mafia and speculate that too much sand and/or water was used in the cement to cut costs and increase their profits.
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| Bridges Now and Then posted Construction of the ill-fated Morandi Bridge, Genoa, Italy, c. 1965. (Community Architect) James Torgeson: Nova did a good program on the bridge and its collapse. Eddie Gough: James Torgeson What was the official cause of failure? James Torgeson: Eddie Gough Hidden corrosion, as I recall. |
Genoa-born Renzo Piano is designing the new bridge for free. "A 3,600-foot-long main steel deck will run across 20 spans, supported by 19 concrete piers. For the most part, the piers will be spaced out in 164-foot increments, except for a pair that has been placed 328 feet apart on either side of the Polcevera River....The project is estimated to cost $229 million, and construction is expected to take 12 months once the site is cleared." [ArchPaper]
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| ArchPaper Two of the bridge’s concrete piers will be spaced twice as far apart as the others in order to span the Polcevera River. (Courtesy Renzo Piano Building Workshop) |
I don't know if the towers are for lighting or what. They are not for stays. My first clue that they were not stay towers is that the towers on the two long spans don't have a pier under them. My second clue is that the replacement bridge "would need to be built with weight-bearing columns rather than stays." The steel deck will be built by the Fincantieri shipbuilding company. "The company plans to produce the components of the bridge spans in its Genoa-Sestieri shipyard and the company’s facility near Verona, and then transport them to the jobsite still in pieces. Onsite, the workers will weld together the pieces of each span while they are still on the ground, then lift the spans into place with strand jacks and a mobile crane." [engineering.com]
The bridge is expected to be done in April, 2020 before the cause of the collapse is known. [enr, EuroNews]
(new window) It turns out that most of this video is a talking head. The construction scene is near the end.
Update:
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| ArchPaper View of the new bridge from below (Courtesy Renzo Piano Building Workshop) |
But what is to guarantee that the owner will do the needed maintenance to control rust?
He has also emphasized how durable his design will be, saying in a recent interview with Dezeen that bridges “should be designed to last 1,000 years.” Piano believes such longevity is an achievable goal: “If you use steel, you add the right protection and you make every piece accessible, so that you can repair or repaint every five to 10 years." [engineering.com]
The bridge is expected to be done in April, 2020 before the cause of the collapse is known. [enr, EuroNews]
(new window) It turns out that most of this video is a talking head. The construction scene is near the end.
Update:
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| Aug 3, 2020 Chicago Tribune, p11 Replacement bridge: Italian air force jets fly in formation Monday over Genoa’s Morandi Bridge, trailing smoke in the colors of the country’s flag. On Aug. 14, 2018, a stretch of the bridge collapsed, sending vehicles plunging to the riverbed below, killing 43. Families of the dead and firefighters who extracted survivors and bodies boycotted the ceremony. (Gian Mattia D’Alberto/LaPresse) [Many businesses have suffered due to the lack of traffic flow. In addition to the two your outage of the bridge, a year ago a tunnel partly collapsed. So the Italian government finally decided they should inspect the infrastructure in this area. They found many problems. And they decided they that they all had to be fixed immediately. So many roads were closed and others were choked with construction traffic. It seems to me that if the government ignored problems for so many decades that they could delay some of the repairs until after the bridge and tunnel were open. [NY Times]] |
A video with some construction scenes
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