Interesting Autocar article

Mr.David

Ever wondered why UK roads are so lumpy?

Steve Sutcliffe

If you’ve ever driven abroad, in western mainland Europe (so let’s say France, Spain, Italy, Belgium etc), you’ll be familiar with that lovely feeling that occurs the moment you drive off the ferry – when whatever car you are driving suddenly seems to be smoother riding, quieter and just more free-flowing across the ground somehow than it had been on the M20.

Well if you’ve ever wondered why, here’s the answer, sort of.



The following is taken from a document about UK roads written by Prodrive, who I’m about to spend some time with finding out why some cars ride and handle well on European roads but badly in the UK, and vice verse, more on which in later blogs…

Here’s a small exert from the Prodrive document:

“”Road surface degradation in continental Europe tends to be dominated by frost damage – which is readily and frequently repaired – or by subsidence, which gives undulations of relatively long wavelengths.

In the UK, frost damage is less frequent but we have an additional problem because the substrate tends to be washed away by the water table [it rains a lot in the UK basically]. This results in much higher frequency, shorter wavelength undulations which ‘excite’ the vehicle suspension at a frequency close to that at which the wheels tend to bounce on their tyres.

"Tyres themselves have little damping but quite a lot of stiffness, particularly when large wheels are specified necessitating tyres of very low profile. The consequent lack of damping has to be catered for by the suspension dampers, increasing their workload and bringing about an extra challenge in their calibration.

"The damaged substrate can also cause the surface to fracture, leaving hard-edged pot-holes that provide longitudinal inputs that cannot be dealt with by the springs and dampers alone. And the frequency of repairs to British road surfaces is far from ideal.

"The texture of British road surfaces, particularly on major highways, is also generally rougher as different systems are used to manage surface water. This has an effect on grip especially in the wet, and in particular on the generation of road noise. Again, managing this adds to the challenge of accommodating both British roads and the UK market’s perception that ‘firm’ is ‘sporty’ without significantly compromising ride quality and vehicle refinement…”

And so it goes on. Which is why tomorrow I’m heading up to Prodrive in a variety of cars – some of which work really well in the UK, some of which don’t – to try to find out how and why they behave the way they do on our uniquely dodgy road surfaces.

And if you lot have any questions you’d like me to put to the Prodrive boys and girls, now’s your chance to ask…



Found the article quite interesting. Another issue is that the steamrollers used for the roads in the UK are apparently quite different to those in continental Europe and also results in different wavelengths and hence frequency of vibration through steering and suspension.

I think Audi (sport suspension) is the perfect example of a car that works well in Europe but feels cack on UK/Irish roads.

Opinions?

Absurdum

The "it rains more" excuse doesn't hold up. Take the monthly rainfall totals for a selection of UK and continental cities - London, Glasgow, Paris, Frankfurt and Barcelona - the evidence there doesn't back it up. I'd say they just don't spend the money maintaining roads properly (same as here).

peasant

btw ...the myth that roads in Germany are perfect and smooth as glass is just that ...a myth.

Ever since Germany had to pump billions into the former east German infrastructure, the roads in the west have suffered years of minimal maintenance and not every road in the east is in good condition either.

Even some motorways are more patchwork than anything else these days.