Railroad tie and method for building or adapting a railroad

1. A railroad tie manufactured from plastic ( 2 ), and further comprising at least two steel bars ( 3 ) embedded in the plastic, wherein the steel bars extend in longitudinal direction of the plastic railroad tie ( 1 ; 41 ; 51 ; 61 ; 71 ; 81 ) and wherein the bars ( 3 ) are situated, in operative condition, at different heights in the railroad tie and are free from mutual connections other than by the plastic, wherein all of the plastic in the railroad tie consists of low density polyethylene.

2. A railroad tie according to claim 1 , wherein at least one of the at least two bars ( 3 ) extends in a first zone (I) of the railroad tie, which first zone is located in operative condition between a longitudinal side of the railroad tie and a sectional plane through the railroad tie located at a first distance from the longitudinal side, and wherein at least one other of the at least two bars ( 3 ) extends in a similar first zone (I) located opposite the first zone at the opposite longitudinal side, and wherein the first distance is less than 25% of the width of the railroad tie.

3. A railroad tie according to claim 2 , wherein at least one of the at least two bars ( 3 ) extends in a second zone (II) of the railroad tie, which second zone is located in operative condition between a top, or bottom, of the railroad tie and a sectional plane through the railroad tie, located at a second distance from the top, or bottom, and wherein at least one other of the at least two bars ( 3 ) extends in a similar second zone (II) located opposite the second zone at the opposite top, or bottom, and wherein the second distance is less than 25% of the width of the railroad tie, and wherein four respective specimens of the at least two bars ( 3 ) are located in four different areas, respectively, each of which being an overlapping area of one of the first zones (I) and one of the second zones (II).

4. A railroad tie according to claim 2 , wherein the first distance is less than 15% of the width of the railroad tie.

5. A railroad tie according to claim 1 , wherein at least one of the at least two bars ( 3 ) extends in a second zone (II) of the railroad tie, which second zone is located in operative condition between a top, or bottom, of the railroad tie and a sectional plane through the railroad tie, located at a second distance from the top, or bottom, and wherein at least one other of the at least two bars ( 3 ) extends in a similar second zone (II) located opposite the second zone at the opposite top, or bottom, and wherein the second distance is less than 25% of the width of the railroad tie.

6. A railroad tie according to claim 5 , wherein the second distance is less than 15% of the width of the railroad tie.

7. A railroad tie according to claim 1 , wherein the railroad tie comprises one or more recesses for receiving attachment means for attaching railroad rails to the railroad tie.

8. A railroad tie according to claim 1 , wherein at least one of the at least two steel bars ( 3 ) has a non-smooth surface.

9. A railroad tie according to claim 1 , wherein ends of the at least two steel bars ( 3 ) are in the railroad tie at a distance from ends of the railroad tie.

10. A railroad tie according to claim 1 , wherein, in operative condition, a top of the railroad tie ( 41 ; 51 ; 61 ; 81 ) comprises at least one recessed top area which is recessed with respect to two spaced apart rail attachment areas of this top.

11. A railroad tie according to claim 10 , wherein the entire portion of the top of the railroad tie ( 51 ) located outside the two rail attachment areas is recessed relative to the rail attachment areas.

12. A railroad tie according to claim 1 , wherein, in operative condition, a bottom and/or sides of the railroad tie ( 61 ) are profiled.

13. A railroad tie according to claim 1 , wherein in two spaced apart respective rail supporting longitudinal segments in the longitudinal direction of the railroad tie, the railroad tie ( 71 ) has a greater height than in other longitudinal segments in the longitudinal direction of the railroad tie located outside these rail supporting longitudinal segments, in a manner such that an underside of the railroad tie ( 7 ), in operative condition, in the longitudinal direction of these two respective rail supporting longitudinal segments, is located lower than in the longitudinal direction of the other longitudinal segments.

14. A method for building or adapting a railroad, wherein a railroad tie ( 1 ; 41 ; 51 ; 61 ; 71 ; 81 ) according to claim 1 is utilized in the railroad.

15. A method according to claim 14 , wherein an existing railroad tie present in the railroad is replaced by the railroad tie ( 1 ; 41 ; 51 ; 61 ; 71 ; 81 ).

16. A method according to claim 14 , wherein during building or adapting of the railroad, drilling is carried out in situ in the railroad tie ( 1 ; 41 ; 51 ; 61 ; 71 ; 81 ) for attaching rails to the railroad tie.

17. A method according to claim 14 , wherein the railroad tie ( 1 ; 41 ; 51 ; 61 ; 71 ; 81 ) is utilized on a railroad bridge.

18. A method according to claim 14 , wherein the railroad tie ( 1 ; 41 ; 51 ; 61 ; 71 ; 81 ) is utilized in a railroad switch.

19. A method according to claim 14 , wherein at at least one location in the railroad where a first rail pair of two parallel, side-by-side rails links up in railroad longitudinal direction with a second similar rail pair in a manner such that the first and the second rail pair are electrically separated from each other, one specimen of the railroad tie ( 81 ) is used such that the ends of the rails of the first and of the second rail pair linking up with each other are each attached to said one specimen of the railroad tie ( 81 ).