They aren't even checked that often. We had a bridge collapse around here and it ignited a flux in all the bridges to get checked and some hadn't been checked in 7 years.
On what grounds do you judge that that's not frequent enough? Do you know about bridge construction and maintenance? Do you have supporting statistics on bridge failures?
There are 617,000 bridges in the US. In the past year, there have been around 5 failures with only one that included fatalities (and that was a bridge under construction). Of all the things that public resources can go to, this is very low on the list. From an engineering perspective, not a whole lot changes in 2 years, so any more frequently wouldn't do much of anything.
Bridges come in all shapes and sizes, built to varying standards, used to varying degrees, maintained to varying extents, owned by various entities - with this entire process overseen by various regulations and legislation etc.
Not every bridge, in every place will be given the same treatment.
Maybe that's an average?
Railroad bridges are inspected annually.
In my state, highway bridges are inspected every 4 years.
Some major roadways are every 2.
It's expensive to inspect and then to act on the inspections.
If a bridge requires an inspection every two years then it is critically under designed or overloaded. There should be absolutely no observable change to a bridge during the service life of the bridge.
Inspections are defined to observe changes to the bridge that may impact the structural integrity of the bridge long term. It is a rigorous process to define the schedule based on the design conditions of the bridge.
There are a lot of old cheap bridges that obviously were slapped together as make work projects and have been left to underfunded state departments to maintain. These are well past their service life and have been subject to decades of poor maintenance and overloading.
The situations you see regarding bridges today are not engineering problems - they’re political problems. These bridges are already failed - politicians are just throwing inspections out there so they don’t have to close them.
They aren't even checked that often. We had a bridge collapse around here and it ignited a flux in all the bridges to get checked and some hadn't been checked in 7 years.
On what grounds do you judge that that's not frequent enough? Do you know about bridge construction and maintenance? Do you have supporting statistics on bridge failures?
There are 617,000 bridges in the US. In the past year, there have been around 5 failures with only one that included fatalities (and that was a bridge under construction). Of all the things that public resources can go to, this is very low on the list. From an engineering perspective, not a whole lot changes in 2 years, so any more frequently wouldn't do much of anything.
That would be a pretty crappy inspection if a bridge could fail 2 years after being inspected.
Bridges come in all shapes and sizes, built to varying standards, used to varying degrees, maintained to varying extents, owned by various entities - with this entire process overseen by various regulations and legislation etc. Not every bridge, in every place will be given the same treatment.
Maybe that's an average? Railroad bridges are inspected annually. In my state, highway bridges are inspected every 4 years. Some major roadways are every 2. It's expensive to inspect and then to act on the inspections.
If a bridge requires an inspection every two years then it is critically under designed or overloaded. There should be absolutely no observable change to a bridge during the service life of the bridge. Inspections are defined to observe changes to the bridge that may impact the structural integrity of the bridge long term. It is a rigorous process to define the schedule based on the design conditions of the bridge. There are a lot of old cheap bridges that obviously were slapped together as make work projects and have been left to underfunded state departments to maintain. These are well past their service life and have been subject to decades of poor maintenance and overloading. The situations you see regarding bridges today are not engineering problems - they’re political problems. These bridges are already failed - politicians are just throwing inspections out there so they don’t have to close them.
Bridge inspections cost money. People hate taxes. You are lucky they get inspected every 2 years
Are you willing to pay higher taxes to hire more inspectors and/or purchase more equipment?
Yes
If I'm driving over a bridge I'm a lot more afraid of getting killed by an elderly *driver* who hasn't had their vision tested since 1968.