matacaster
On Moderation
Bridge strikes cost a great deal of time and money, not to mention delays. Many bridges only get the odd strike, but a mall number seem disproportionately prone to being struck.
Would it not be possible in these cases to construct a simple frame of 3 very substantial RSJs (as used on tall buildings), placed say 20 feet before each of these serially offended bridges to ensure that no overheight vehicles got near the bridge. Using RSJ's would mean the installation cost would be low as they are freely available and don't need any fancy design.
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If struck, the worst that could happen would be a bent bridge protector and a mangled lorry etc.
That would still leave the problem where arch bridges were only passable at full height near the crown, with lorries advised to go through the middle of the bridge. Here, I suspect some form of enhanced traffic lights might be needed which used a sensor on top of my aforementioned frame to detect any vehicle which would be overheight at either side of the bridge and cause traffic lights cause vehicles to stop.
Obviously there may be some issues with this back of a fag packet solution, but I am hoping that others can not only pass constructive criticism and improve upon the outline idea. After all, the cost of bridge strikes is substantial and the knock on delays far afield help to engender the railways as being unreliable with endemic delays in the public mind.
Would it not be possible in these cases to construct a simple frame of 3 very substantial RSJs (as used on tall buildings), placed say 20 feet before each of these serially offended bridges to ensure that no overheight vehicles got near the bridge. Using RSJ's would mean the installation cost would be low as they are freely available and don't need any fancy design.
I-----------I
I I
I I
If struck, the worst that could happen would be a bent bridge protector and a mangled lorry etc.
That would still leave the problem where arch bridges were only passable at full height near the crown, with lorries advised to go through the middle of the bridge. Here, I suspect some form of enhanced traffic lights might be needed which used a sensor on top of my aforementioned frame to detect any vehicle which would be overheight at either side of the bridge and cause traffic lights cause vehicles to stop.
Obviously there may be some issues with this back of a fag packet solution, but I am hoping that others can not only pass constructive criticism and improve upon the outline idea. After all, the cost of bridge strikes is substantial and the knock on delays far afield help to engender the railways as being unreliable with endemic delays in the public mind.