Been checking out the workers doing structural surveys on the old railway bridge (the main line through from oop north to London) out the back of my work and was just pondering how they actually check that something is still able to withstand daily pummeling from several hundred tons of stone, metal and trains.
They appear to be working their way along, drilling holes and generally fiddling about etc…

I mean, if something has fallen down, then that’s obvious, it wasn’t strong enough. If something is being built, then the materials and structural technique can be tested on a smaller scale and appropriate materials and methods used. But if a bridge or a building is already there, and maybe has been for hundreds of years, then how do they check it’s still strong enough without actually testing it to the point of breaking?

In the words of Gaz Top….How?

MrsP is a bridge engineer & does a fair few inspections. Lots of measurements, lots of information about strengths of various materials, loads, wind speeds etc., then lots of calculations.

Oh, I thought a worker in a hiz viz jacket just gave it a few kicks at strategic points and if nothing fell off or over it was a good ‘un.

Given that most of our railway infrastructure is 150 years old and was built by men who didn’t have calculators and computers but learnt from earlier disasters, therefore over engineered and over built that why its still in use. My belief is if it hasn’t moved, cracked or fallen down its perfectly safe. But then again the elf and pasty brigade need to cover themselves to ensure a fat bonus at the end of the year.

Maybe what they should concentrate on is managing rain water; because in the UK it rains, rather than inspecting the after effects.

My belief is if it hasn’t moved, cracked or fallen down its perfectly safe. But then again the elf and pasty brigade need to cover themselves to ensure a fat bonus at the end of the year.

I’ll stick with the people who are trained and have the knowledge and skills to actually know rather than guess.

(Was it you that surveyed the bridge in Boscastle by the way 😐 )

Nope but if you carry out no maintenance to manage rain water, build buildings and a large car-park on the land directly above/in front of the bridge reducing soak away capacity and then expect it all to be Ok when it rains….

I lived in Cambridgeshire in 1997 when they had the worst floods for “a hundred years”, “that were once in a life time” 🙄 . Reports after the event said most of the flooding was either caused by or exacerbated by poor decision making; either building on flood plains or taking water management ‘maintenance holidays’.

Victorian infrastructure, where modern ill-conceived development does’t impact, remain unaffected by rain as unsurprisingly it rained (a lot) during Victorian times and their engineers made sensible decisions as they knew rain water is dangerous and needs to be respected.

What about the long-term effects of rainwater leaching through the stonework of Victorian bridges and emerging underneath as stalactites? Does that do any harm? Presumably in limestone areas the rain is carrying out the same dissolving process that formed caves?