View Single Post
  #5   Report Post  
The Natural Philosopher
 
Posts: n/a
Default

Paul Mc Cann wrote:

In article ,
says...

I believe that a bitumen surface is applying a mix of small gravel and
bitumen, an asphalt surface is bitumen mixed with a wide range of
particle sizes( like a concrete mix). Asphalt is ideally applied as a
much thicker layer, with a much heavier roller as it is a less flexible
mix, but takes greater loadings. IME, both are poor surfaces compared
with concrete.



??

Haven't seen them building concrete roads in years. They were usually an
un-mitigated disaster.



No, they can and do last ages. If built properly. Cheap too. Hrad
wearing, but nosiy and low grip.


Asphalt in particular suffers from surface "heave" if the
subsoil/base is not stable.



Concrete will crack in similar circumstances. Once it cracks and rain
gets in, followed by frost, its well on its way to Valhalla.

I think they are both ugly but the alternative of gravel drove me nuts.

Some years back we replaced gravel (P.I.A.) with what I think the
installer caled tarmacadam. He gave me the impression asphalt was very
heavy duty applications,and mostly suitable for roads, bit of an over
kill for drives.


The original macadam roads were IIRC crushed stone chippings that bedded
down. MOT type I etc. Tarmacadam (tarmac) was the application of a
layer of hot tar to the surface into whch chippings are rolled. Tough
flexible and reasonably hard wearing, and NO DUST (the bane of the 30's
motorists). Its what most B roads are. Coulur depends on what colour
chippings are rolled in. Flint makes for a briown road, granite for a
grey/black one.


Asphalt is I think a deeper layer of tar and stone filler, that is super
smooth and what best motorways are made of. You can even add ground up
car tyres for super quite and exta good grip.

Bitumen? Not sure what that is - maybe a cold applied layer with
chippings thrown on top. Sets by solvent evaoporation?



Bitumen to him was something cowboys specialised in.

Whatever he used for us it is standing up beautifully.