Before building a way, let us find the main requirements for it.
- Single breakdown can't block traffic in any direction.
- In case of no breakdowns, a way in any direction is granted.
- A way's capacity can be increased in any direction if necessarily automatically (with a penalty to the capacity in other direction).
- Trains reversing ability.
BETA version, under testing!
The four-line ways is an experimental construction of a way with a high capacity. One line A in one direction, one line in the other direction G and two lines H and Q for both the directions. The power of the construction is that no broken train can block trains movement in any direction.
How does it guaranteed? Let's have a look at the train, broken on the A line. There are to possible situations: it will block only line A or it will block the line-changer I. Any case, lines G and Q are free and line Q can be used in the direction, equal to direction of line A. If a train is broken on the H line, it can block lines A (on line-changer I) or line Q on the line-changer J, but not both of them. Than paars of lines G and Q or G and A are free for both the directions movement. Situation with blocking G and Q is simmetric.
Connections of four-line ways, both the intersections and T-junctions are not designed yet.