"Nightjar" wrote in message
...
On 19-Feb-18 2:14 PM, DerbyBorn wrote:
Was thiunking as I drove along a lane with deep ruts where the tarmac met
the grass - and wondering what damage it may have done to the vehicle -
that such lanes are a problem - the tarmak crumbles at the edges and
keeps
breaking away.
Clearly constucting a road with curbs (kurbs?) woudld be costly - but
having seen a machine continuously casting a centre barrier I wondered is
a
machine could do it.

Imagine a rotating trenching mechanism - toothed wheel - followed up by a
concrete mixing and filling machine - possibly dropping in some
reinforcement.

Could it work?

The problem with kerbs is that they trap water and require drainage to be
added. The simpler solution is to build the roads a couple of feet wider
and paint a white line a couple of feet in from the edge.

That doesnt work either, because inevitably some need
to go off the edge and It breaks up with they do that.

Its must another example of no perfect approach, different ways
of doing things with different advantages and disadvantages.

If there was one perfect approach, everyone would do it like that.

That provides the edges with just enough protection from the effects of
heavy vehicles.

Nope, because some need to come off the road anyway.