PowerSwitch

Hi,
This is my first post and was prompted by replies to a post in the general forum about looking forward to when it will be safe to cycle on the roads again.
Let us suppose that some white elephant road project is completed just before the ordure hits the mechanical air circulation device.
Can anyone suggest how long such a construction would last given that it will be massively over engineered for the lightweight vehicles that will predominantly use it? i.e bicycles.

kind regards

Laurie

my guess is ...

200 years with no maintainence - if all it carries is bycyles

50 years (woith repairs) if it carries a continuing amount of road frieght (which I cant see just endeding, much as that would be nice)

why do you ask?

monuments to a bygone era?

Some victorian structures have been pounded to death daily for a century and they are still going strong (albeit with some repairs).

I can see the Forth bridge still carrying trains in another 100 years.

My guess is less. Nature is a lot stronger than 40Ton lorries.

Most roads are tarmac.
Narrow country lanes become almost impassible after a couple of
years of no maintainance and very low traffic. Weeds take hold
on the gravel loosened by frost action in a matter of weeks. Roots
from nearby trees start breaking up the surface after a couple of
years. Frost action deepens minor flaws into deep potholes in a
few years, even without traffic to further loosen the structure. Over
a period of decades good old earthworms will raise surrounding
ground levels, and soil will spill over on to the surface of the road
and it will disappear completely.
Seedlings will take root in the cracks and in a decade the road will
resemble a wooded copse. Growing trees and water table changes
and floods will cause sections to buckle or subside.

Of course, it will take longer for the bigger and the deeper foundation
roads, and concrete lasts much better than tarmac. I am used to
using old contrete roads on WWII airfields, they hold up reasonably well.
Unrepaired rural East european tarmac roads have more pot holes than
tarmac, but the original build standard was probably lower.

Some long stretches of roman road still survive, in relatively original
condition, because they continued to be useful roads and were on
a human scale to repair and maintain. However, many have disappeared. We will never have the manpower or local resources
to patch and maintain all our tarmac roads post oil. Most will be
dug up and used as a low grade energy source.

You could look here for some hints on how unused roads fare with time:

http://www.kiddofspeed.com/

I agree, and the pictures of the roads around Chernobyl show it clearly. You only need to take a look at the pavement or edge of the road next time you are walking somewhere, and you can see nature starting to break apart the tarmac.

This is why the local councils employ people to walk round with herbicide spraying the edges of the roads and paths every few months.

I think it would be a mistake to imagine all road transport suddenly ceasing and the roads being just one long skate park.

A much more realistic comparison will be with the last war. There will be some oil to be found, or made from coal or organic waste, for a long time to come. We can imagine that petrol will be strictly rationed and probably unvailable to all but the super-rich and essential services. Local road frieght will continue, but most long haul journeys will be by rail (or canal).

So there's no reason to think that maintenance of the roads will stop. There will be much less needed of course because there will be only a fraction of the current traffic.

It's going to be great for those rich people who can get petrol. They will have the roads almost to themselves. Again this is nothing new. It was the situation in the UK up until the late 1950s when mass car ownership began.

So if you're imagining some kind of bicycling utopia think again. Yes, us poor mugs will be on bikes, but we'll be buffeted by the slip-stream as the rich guys speed past in their gas-guzzlers. The reduced road maintenance will probably make 4x4s even more popular than they are now!

MacG wrote:You could look here for some hints on how unused roads fare with time:

http://www.kiddofspeed.com/

Thanks for the link. Very chilling viewing.

MacG wrote:You could look here for some hints on how unused roads fare with time:

http://www.kiddofspeed.com/

Actually I didn't really agree that the photos I looked at on this site showed how bad things can get - the ones I saw looked pretty good for not-great soviet era roads that had laid dormant for decades. But maybe the pics I looked at weren't representative.

I thought the pics made intersting viewing anyway, it's a errie landscape with traces of humanity once there but now so distant.

I wonder what other parts of the world will look like that one day....

This topic reminds me of the collapsed road by Mam Tor, near Castleton/Edale:

http://www.tracklogs.co.uk/cgi-bin/publ ... =mtb202_05