Accident in Baltimore, how and why the bridge collapsed after the impact with the cargo ship

On March 26, 2024 at 1:30 local time (6:30 Italian) the container ship From therewhich had just left the port of Baltimore for Sri Lanka, hit a bridge pylon Francis Scott Keydestabilizing the structure and making it partially collapse into the river. At the time of the accident, there were several cars and around 20 workers on the bridge. At least 7 vehicles fell into the water and currently the budget is one dead and six missing, while there are no injuries among the crew members. The police are working to search for the missing. As evidenced by a video collected by a surveillance camera, shortly after the ship left the port its lights went off turned off for several seconds and the smoke. Then the lights went on turned it back on and again turned off as the ship began to turn towards the bridge pylon. A few moments later the collision which caused the collapse of the structure. But what were the causes behind this disaster, and why did the bridge collapse so easily? Let's clarify this through an unpublished story 3D reconstruction.

What are the hypotheses on the causes of the accident

At the moment a possible hypothesis to explain what happened comes from David McFarlanethe director of Maritime Risk and Safety Consultants Ltd, a private Scottish company that deals with maritime investigations. According to what he told Sky News, some type of incident may have occurred on the ship failure to the ship's engines. The hypothesis seems confirmed by the governor of Maryland Wes Moore: According to his statement at the press conference, the crew noticed a loss of power before the crash. Obviously we cannot know for sure at least until all the tests have been carried out necessary expertise.

Another hypothesis is that it was a navigation error. But this is it less likely because they were present on board at the time of the collision 2 pilots, so it is unlikely that either of them saw the bridge pylon. Not to mention that theabsence of lights on board it could be a sign of a malfunction of the ship.

In any case, according to the Baltimore Police there is no evidence to believe that the impact was the result of a deliberate action and, according to the Baltimore FBI and the Secretary of Homeland Security Alejandro Mayorkasit would seem that we can also exclude the hypothesis of a terrorist act.

Why the Baltimore Bridge Collapsed

Opened in 1977 The Francis Scott Key it is – indeed, it was – one of the main connecting roads of the city. Conceptually this bridge had as its key element a steel metal arch to support the road, which was in fact suspended. In turn, however, this arc it rested on the pylons. The ship hitting the reinforced concrete pylon removed a support from this arch and therefore the structure he no longer had a point of supportcollapsing and destabilizing a large part of the bridge.

Then consider that the pylon hit was that of the greater light – therefore the longest stretch of road between one pylon and another – and this did nothing but increase the instability of the structure. This was also confirmed by the structural engineer Ian Firth to the BBC:

The stand is a very, relatively, fragile structure, it is a kind of easel with individual legs. So, the bridge simply collapsed as a result of this very large impact forceAnd.

To this we must add that the bridge had a reticular structure, made up of many interconnected elements. As it is easy to imagine, when a structure of this type loses stability it collapses very quickly because each piece “pulls down” the others. However, it must be considered that – as the spokesperson for the Baltimore Fire Brigade also confirmed Kevin Cartwright – an investigation will soon be opened which will also involve structural engineers to understand what the conditions of the bridge were at the time of the collapse.

Could something similar happen with the Messina Strait Bridge?

The answer is no, since the bridge will be a single spanTherefore without pylons. If he also passed a cargo ship like Dali, she would have nothing to hit. Furthermore, the bridge has a minimum height compared to the water level (called frank) which varies from 50 to 65 meters depending on the stretch we consider, therefore only ships with an adequate height will pass through there.

To give a comparison, this is a franc in line with values ​​of other bridges in the world. The famous one Golden Gatefor example, has a franc of 67 meterswhile for the Francis Scott Key it is 56 meters, therefore similar to that of the future Strait Bridge.