Patent Application
20080017727
The invention relates to a rail with a continuous support in the rail trough of a steel construction or by concrete slabs and the like, attached therein by means of a two-component embedding material.
In the area of roads, road intersections, green spaces and the like it is often required or desired to sink the rails for railroads into the road surface or into green areas in order to ensure that the tires of other vehicles can easily roll over them or to achieve a desired optical design.
For street cars, high grooved rails are used in a customary manner with a high section modulus in the load direction and with a rail base width of up to 18 cm and larger and are positioned on a compacted subgrade, whereby an exact spacing takes place by means of metallic spacing means to construct a track. An extensive planeness of rail head or of running head and guiding head of the grooved rail and the road surface or design surface is achieved by means of filler material, optionally with a pavement.
A track with rails sunk into a surface can also be constructed in that one or more concrete slab(s) in succession are used as a supporting structure with two U-shaped recesses in the longitudinal direction, a so-called rail trough to hold Vignol rails. In order to mount the Vignol rails in the concrete slab, while ensuring a precise spacing of the rails from one another, an encasement reaching up to the head is carried out in the rail trough after an adjustment, with a potentially elastic two-component material such as, e.g. polyurethane foam or the like. A rail mounting of this type to form a track is possible in an advantageous manner both in concrete slabs and in steel constructions, whereby a continuous support of the rails is made possible, so that even Vignol rails with a lower moment of inertia can be used.
However, a mounting of Vignol rails according to the above method in a rail trough has the disadvantage that high volumes of encasement material are necessary to embed or fix the rails in the rail trough. Furthermore, it is expedient with respect to the wheel flange of the wheels to lower the level of the rail embedding on the interior side of the track, which can mean an additional expenditure. Finally, the head width of a Vignol rail is small with respect to the base width, which increases the lateral surfaces of the potentially soft embedding material in the road surface area and augments the danger of wear, and also renders necessary high encasement volumes for embedding the rails.
The object of the invention is to create a rail of the type mentioned at the outset which avoids the disadvantages stated, can be connected by means of fishplates, is very cost-effective in terms of a production with a head hardening, requires a low volume of embedding material for the fixation in a rail trough and achieves a high stability and durability of the track.
With a generic rail this object is attained in that the rail is embodied as a grooved rail with a running head, a guiding head, a web and a rail base, has a greatest height with respect to the support area of the rail base of more than 10.0 cm, but less than 12.4 cm, a total width of the base of more than 10.1 cm, but less than 14.0 cm, a width of the running head of essentially 5.1 cm to 6.3 cm, and two fishplate recesses arranged on both sides of the rail web, whereby the fishplate recess facing the guiding head with respect to the cross section of the rail has a width of the planar basis of at least 1.64 cm.
The advantages achieved with a rail according to the invention with the installation in a rail trough result in a synergetic manner from a high cost-effectiveness during track construction and particularly good track properties during heavily loaded operation of the same. A use of a grooved rail minimizes in a favorable manner the exterior surface of the embedding material towards the road surface, whereby also its cross-sectional profile is directed towards a high stability and load capacity during the operation of the track and towards a negotiability for essentially all conventional rail wheels. The fishplate recesses are advantageously dimensioned such that the bores for mounting the connecting pieces sufficiently ensure their mechanical load capacity.
In order to favorably transfer the wheel load into the subgrade of the rail trough, which can have a rubber overlay, the minimum total width of the rail base is dimensioned, whereby the largest width of the same according to the invention is determined with respect to minimizing the rail trough cross section. Also the height of the grooved rail according to the invention is defined with a dimension that renders possible a small rail trough depth with high load capacity and thus an advantageous and economic embodiment of the foundation component(s).
A particularly advantageous embodiment of the grooved rail according to the invention can be achieved if, perpendicular to the support area of the rail base, the guiding head and the rail base flange on the same side have an essentially equal projection with respect to the web of the rail, and that on the opposite side the projection of the rail base flange extends beyond the projection of the running head, preferably extends beyond it by more than 1.0 cm.
This cross-sectional design can on the one hand reduce the support function of the rail base during a loading of the running head in curves and thus reduce the highest surface pressure at the flange end of the same and achieve approximately a favorable rectangular shape of the perimeter of the rail cross section.
With respect to laying the rail according to the invention largely without problems to form bent tracks, but also for a transfer, adapted to the subgrade, of the compressive forces from the respective axle loads, it is advantageous if the rail cross-sectional area is less than 75.0 cm2, but more than 69.0 cm2, and if the moment of inertia with respect to axis xx exceeds an amount of 800.0 cm4 and the moment of inertia with respect to axis yy is lower than 650 cm4.
By means of the rail cross-sectional area and in particular by the respective moment of inertia within the limits according to the invention, the elastic deformation of the rail can be adjusted favorably to the installation components.
A particularly favorable setting of the maximum tensions during a bending by the wheel load can be achieved if the center of gravity of the rail cross-sectional area at a height of the axis xx is in the range of 0.456 to 0.54 times the rail height.
For a greater stability of the grooved rail in the embedding in the rail trough during use at high axle pressures and/or speeds particularly in narrow curves of the track, the rail cross-sectional area is advantageously embodied such that the connecting line from the interior part of the running head to the outmost projection part of the projecting rail base flange has an angle in the range of 30° to 35°.
If furthermore at least the running head has a greater hardness and/or wear resistance than the web part of the rail, i.e., that at least the running head, advantageously the running head and the guiding head of the grooved rail, are hardened, the service life of the track can be considerably extended even in heavily loaded operation.
According to the invention, the cross section of the grooved rail is designed such that the rail ends can be connected to further rails or switch parts by means of fishplates with through bolts. The rails can thus be reliably linked, even if a front-face welding of the ends should not take place.
Finally, it can be advantageous for driving on the track during winter operation at temperatures below freezing, in particular in the vicinity of switches, if the grooved wall between running head and guiding head has holes spaced apart downward, in particular in the area of switches, which holes are preferably connected to water discharge means in the embedding material or in the mounting system.
The rail according to the invention is to be explained in more detail below on the basis of two representations. They show:
With a total width C of the rail base 4, a greatest height A of the grooved rail is embodied such that—in cross section—a connecting line from an interior delimitation of the running head 1 to the outmost part of a support area 40 of the flange 41 of the rail base 4 has an angle α of more than 30°, but less than 35°.
The height H of the center of gravity S of the cross-sectional area of the grooved rail is (0.456 to 0.54) times the greatest height H.
A fishplate recess facing the guiding head has a planar basis with a width D of at least 1.64 cm, so that it is possible to ensure sufficient stability and strength of a bored fishplate.
In the lower area of the groove between running head 1 and guiding head 2, holes 21 are indicated in dashed lines, which holes are connected to a water discharge means 7 and are thus able to keep the groove clear of accumulated rain water or melt water.
Between support area 40 of the rail base 4 and the base area of the rail trough in the structural part 5, an overlay 61 can be positioned in varying strength and with selected damping properties.
| Number | Date | Country | Kind |
|---|---|---|---|
| A 1630/2004 | Sep 2004 | AT | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/AT05/00369 | 9/14/2005 | WO | 8/21/2007 |
