Peter Moylan <pe...@pmoylan.org.invalid> wrote:
> On 07/06/22 18:38, Hibou wrote:
> >
> > I meant that we like to think of railway lines as fixed, solid,
> > reliable things, though in fact they can move down quite a bit under
> > a train's weight.
>
> They can also buckle in very hot weather. The gaps between rails are
> supposed to allow for this, but those gaps were, in most cases, designed
> before global warming became a topic of conversation.
Is Australia backward, or have you failed to keep up?
In Europe rails are welded, no gaps. (except near stations)
Thermal forces are kept in check by using heavy concrete blocks
connected by steel rods as sleepers.
(laid in broken stone, not gravel)
In winter the rails are heated before welding,
to make sure that the rails are tension-free
at about the right temperature.
High speed trains such as the French TGV
would not be possible otherwise,
Jan