It will be something I want to watch for.
Me too. I'm not an engineer, but I've always had a fascination for bridges. I tend to like bridges that don't collapse. But those that have collapsed are remembered better – with morbid fascination.
Possible reasons for the bridge failure that I've read so far (at various news sites, including BBC, CBS, CNN, Washington Post):
- Steel reinforced concrete is known to deteriorate after about 50 years. The steel buried inside the concrete rusts enough to weaken the structure. It can be addressed with major reconstruction efforts. This bridge was built in 1967. At the time of the collapse, the bridge was undergoing some major reinforcement this summer.
- This bridge was said to be built using new (for the time) steel/concrete techniques that have not been used since. I'm not sure why, but I assume the technique was less expensive, but led to weaker than intended structures.
- One Italian bridge engineer was quoted as saying this bridge was designed to carry much lighter loads than it has been routinely exposed to for decades. It was a failure waiting to happen.
- Not nearly enough maintenance (as mentioned above by others).
- The torrential rain storm. Heavy rain and high winds? Would this alone be enough to cause failure? Probably not, but it cannot be ignored.
Stay tuned. As usual, there are news stories of Italian leaders who are calling for criminal investigations. Why look for someone to blame (the bridge designer died in 1989) when the bridge clearly needed major repair or replacement. I do not understand the Italian legal system.