(1 November 2014, 14:54)bigpaul Wrote: I do find the idea that somehow modern transport infrastructure will last for a long time, 30 years or even indefinitely to be fanciful at the very least, a bit like the Yanks who think oil will last forever.
Please refer to paragraph 2.27 in the following DfT "Design Manual" for Roads:
http://www.dft.gov.uk/ha/standards/dmrb/...hd2606.pdf
This confirms a standard design life of 40 years for Roads.
As for bridges, please refer to section 3.1 in the following document:
http://www.dft.gov.uk/ha/standards/dmrb/.../bd981.pdf
Again this confirm all new bridges have a design life of 120 years.
So although you may not believe it, I can assure you it is the case that infrastructure is "Designed" to last.
And also you have all the examples of historic examples of existing roads and bridges which simply haven't disintegrated after 20 years.....