Railroad and railroad tie for use in such a railroad

Abstract

A railroad tie (3) for use in a railroad has been designed according to the invention in such manner that a first tie balancing ratio is between 0.45 and 0.50, and a second tie balancing ratio is between 2.5 and 10.0. The first tie balancing ratio is defined as a quotient, of which the numerator is equal to the sum of the footprint surface areas of a first longitudinal end segment (Al) and a second longitudinal end segment (A2), and of which the denominator is equal to the footprint surface area of the whole railroad tie (3). The second tie balancing ratio is defined as a quotient, of which the numerator is equal to the sum of the footprint surface areas of a first rail supporting longitudinal segment (Bl) and a second rail supporting longitudinal segment (B2), and of which the denominator is equal to the footprint surface area of an intermediate longitudinal segment (C). Said footprint surface areas are defined as the surface areas as seen in vertical bottom view of the railroad tie. The invention provides a reliable solution for preventing center bounding and end bounding of railroad ties in a ballast bed.

Description

Title: Railroad and railroad tie for use in such a railroad.The present invention relates to a railroad, comprising a ballast bed, a railroad tie, which is manufactured from at least plastic and which is resting at and / or in the ballast bed, and a first rail and a second rail which are fastened on top of the railroad tie. The invention further relates to a method of building such a railroad, as well as to a railroad tie for use in such a railroad.WO 2011 / 103284 Al discloses a plastic railroad tie, which has been formed to prevent “center bounding” of the railroad tie relative to the ballast bed of the railroad.Center bounding means that the railroad tie in unloaded condition substantially rests on ballast under a midsection of the railroad tie, since as a result of ballast degradation two “gaps” have arisen in the ballast bed under at least two rail supporting sections of the railroad tie. This is illustrated by the attached Figs. 1A-1B, which show a vertical cross-section through a first railroad tie 1003 with an underlying ballast bed 1002 of a railroad, wherein the vertical cross-section is perpendicular to the track longitudinal axis of the railroad. The first railroad tie 1003 is not according to the present invention, it is a simple plastic railroad tie having the shape of a three-dimensionally fully rectangular beam. The two downward directed arrows 1011 and 1012 shown in Fig. 1A are representing load which is exerted via rails on the first railroad tie 1003 at the moment when a train is moving over the rails. Fig. 1A shows, in a somewhat exaggerated manner, how the first railroad tie 1003 bends under the load exerted thereon and how ballast of the ballast bed 1002 is compressed thereby. Fig. IB shows the situation after the train has passed over the first railroad tie 1003, whereby in Fig. IB the first railroad tie 1003 has returned into its unloaded straight form. In Fig. IB it can further be seen that the ballast bed 1002 under the first railroad tie 1003 has acquired a kind of W-shape as a result of many train passages. As a result of the W- shape two gaps 1006 and 1007 have arisen between the first railroad tie 1003 and the ballast bed 1002. Between the two gaps 1006 and 1007, under the midsection of the first railroad tie 1003, the ballast bed 1002 has an elevation 1008 on which the first railroad tie 1003 in its unloaded condition is substantially resting. Hereby the first railroad tie 1003 has become “center bound”. In practice, center bounding canalready arise some weeks after a railroad was newly built, or some weeks after a ballast bed was renovated under the railroad ties.The above-mentioned document WO 2011 / 103284 Al mentions in paragraph

[0007] that center bounding has the disadvantageous effect that thereby railroad ties are more susceptible to breaking. In addition it has to be noted that an important function of railroad ties is to distribute the load, transmitted via the rails to the railroad ties, as good as possible over the ballast. This function is affected by center bounding. This is another important disadvantage of center bounding, which leads to reduced stability of the railroad, and which furthermore leads to increase of energy consumption needed for moving trains that are passing over the railroad ties, which due to center bounding are bending relatively much. It will further be appreciated that railroad ties being center bound lead to extra periodical maintenance of ballast beds and railroad ties of railroads, which brings along considerable costs.In order to reduce center bounding, the above-mentioned document WO 2011 / 103284 Al proposes to design a railroad tie with a midsection of the bottom of the railroad tie having a round shape, best seen in Fig. 3 of WO 2011 / 103284 Al. A drawback of this embodiment of WO 2011 / 103284 Al is that, due to the fact that the railroad tie in the course of time sinks further into the ballast, the bottom width by which the round midsection of the railroad tie rests on the ballast becomes ever larger in the course of time, and that thereby the preventing of center bounding will be undone more and more in the course of time.It is noted that a railroad tie, instead of being “center bound” relative to a ballast bed, can also be “end bound” relative to a ballast bed.“End bounding” means that, as a result of ballast degradation, a railroad tie in unloaded condition substantially rests on ballast under the two longitudinal end segments of the railroad tie. An example of end bounding is shown in the attached Figs. 1C-1D, which show a vertical cross-section through a second railroad tie 2003 with an underlying ballast bed 2002 of a railroad, wherein the vertical cross-section is perpendicular to the track longitudinal axis of the railroad. The second railroad tie 2003 is not according to the present invention, it is a simple plastic railroad tie having the shape of a three-dimensionally fully rectangular beam. The two downward directed arrows 2011 and 2012 shown in Fig. 1C are representing load which is exerted via rails on the second railroad tie 2003 at themoment when a train is moving over the rails. Fig. 1C shows, in a somewhat exaggerated manner, how the second railroad tie 2003 bends under the load exerted thereon and how ballast of the ballast bed 2002 is compressed thereby. Fig. ID shows the situation after the train has passed over the second railroad tie 2003, whereby in Fig. ID the second railroad tie 2003 has returned into its unloaded straight form. In Fig. ID it can further be seen that the ballast bed 2002 under the second railroad tie 2003 has acquired a kind of W-shape as a result of many train passages. As a result of the W-shape two gaps 2006 and 2007 have arisen between the second railroad tie 2003 and the ballast bed 2002. Relative to the two gaps 2006 and 2007 the ballast bed 2002 has the three elevations 2008, 2009 and 2010 according to said W-shape. Of these, the two end elevations 2009 and 2010 are lying under two longitudinal end segments of the second railroad tie 2003, respectively, while the mid-elevation 2008 is lying under a midsection of the second railroad tie 2003. In Fig. ID it can be seen that the second railroad tie 2003 in its unloaded condition of Fig. ID substantially rests with its two longitudinal end segments on the two end elevations 2009 and 2010 of the ballast bed 2002, respectively. Hereby the second railroad tie 2003 has become “end bound”. In practice, end bounding can already arise some weeks after a railroad was newly built, or some weeks after a ballast bed was renovated under the railroad ties.End bounding brings along disadvantages which are similar to the aboveexplained disadvantages of center bounding.It is an object of the present invention to provide a more reliable solution for preventing, in railroads, center bounding and end bounding of railroad ties which are manufactured from at least plastic, so as to obtain considerable cost savings related to maintenance of railroads and energy consumption of trains. For that purpose the invention provides a railroad according to the appended independent claim 1, a method of buiding such a railroad according to the appended independent claim 5, and a railroad tie according to the appended independent claim 6. Preferable embodiments of the invention are provided by the appended dependent claims 2-4 and 7-9.Hence, the invention provides a railroad comprising:- a ballast bed,- a railroad tie, which is manufactured from at least plastic and which is resting at and / or in the ballast bed, and- a first rail and a second rail which are fastened on top of the railroad tie, wherein the railroad tie has a tie longitudinal axis and the railroad has a track longitudinal axis, and wherein the track longitudinal axis is substantially perpendicular to the tie longitudinal axis, and wherein a horizontal reference condition of the railroad tie is defined to correspond to an imaginary orientation of the railroad tie together with the first rail and the second rail, said imaginary orientation being such that each of the tie longitudinal axis and the track longitudinal axis extends horizontally, and wherein, as considered in said horizontal reference condition of the railroad tie:- the railroad tie extends along the tie longitudinal axis from a first tie end to a second tie end,- the first rail and the second rail in a vertical top view have a first rail centre line and a second rail centre line, respectively, which are parallel to the track longitudinal axis, wherein the first rail centre line and the second rail centre line have a centre-to-centre distance (M) relative to one another,- an overall tie length (L) of the railroad tie, said overall tie length being measured along the tie longitudinal axis between the first tie end and the second tie end, is larger than or equal to 150% of said centre-to-centre distance (M) between the first rail centre line and the second rail centre line, with the characterizing definitions, that, as considered in said horizontal reference condition of the railroad tie and as considered in a vertical bottom view of the railroad tie:- a footprint surface area of the whole railroad tie or of a part of the railroad tie is defined as the surface area of said vertical bottom view of the whole railroad tie or of the part of the railroad tie, respectively,- a first rail supporting longitudinal segment (Bl) of the railroad tie is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis, extend between two first longitudinal positions, which are situated along the tie longitudinal axis on two mutually opposite sides, respectively, of the first rail centre line, wherein each of the two first longitudinal positions has a distance to the first rail centre line equal to 25% of said centre-to-centre distance (M),- a second rail supporting longitudinal segment (B2) of the railroad tie is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis, extend between two second longitudinal positions, which are situated along the tie longitudinal axis on two mutually opposite sides, respectively, of the second rail centre line, wherein each of the two second longitudinal positions has a distance to the second rail centre line equal to 25% of said centre-to-centre distance (M),- an intermediate longitudinal segment (C) of the railroad tie is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis, extend between the first rail supporting longitudinal segment (Bl) and the second rail supporting longitudinal segment (B2),- a first longitudinal end segment (Al) of the railroad tie is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis, extend between the first tie end and the first rail centre line,- a second longitudinal end segment (A2) of the railroad tie is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis, extend between the second tie end and the second rail centre line, and with the characterizing features, that a first tie balancing ratio is between 0.45 and 0.50, wherein the first tie balancing ratio is defined as a quotient, of which the numerator is equal to the sum of the footprint surface areas of the first longitudinal end segment (Al) and the second longitudinal end segment (A2), respectively, and of which the denominator is equal to the footprint surface area of the whole railroad tie, and that a second tie balancing ratio is between 2.5 and 10.0, wherein the second tie balancing ratio is defined as a quotient, of which the numerator is equal to the sum of the footprint surface areas of the first rail supporting longitudinal segment (Bl) and the second rail supporting longitudinal segment (B2), respectively, and of which the denominator is equal to the footprint surface area of the intermediate longitudinal segment (C).Briefly summarized the invention is formed by the combination of the special key-features that:I. the first tie balancing ratio is between 0.45 and 0.50,II. the second tie balancing ratio is between 2.5 and 10.0, andIII. the “footprint surface area” of the whole railroad tie or of a part of the railroad tie, as used in the first tie balancing ratio and the second tie balancing ratio, is defined as the surface area of said vertical bottom view of the whole railroad tie or of the part of the railroad tie, respectively.These key-features I, II and III are based on insights obtained by the inventor by combining inventiveness and research.The first key-feature I relating to the definition and the value of the first tie balancing ratio according to the invention is based on the insight of the inventor that a railroad tie according to this key-feature I can be supported in a reliable and well-balanced manner by a ballast bed both in the two longitudinal end segments (Al, A2) and in the intermediate longitudinal segment (C), i.e. while it is prevented that the railroad tie would substantially rest with the intermediate longitudinal segment (C) on the ballast bed (“center bounding”) and while it is prevented that the railroad tie would substantially rest with the two longitudinal end segments (Al, A2) on the ballast bed (“end bounding”).The second key-feature II relating to the definition and the value of the second tie balancing ratio according to the invention means that downward facing contact surface of a railroad tie with an underlying ballast bed according to this key-feature II in the intermediate longitudinal segment (C) of the railroad tie extends to a relatively lesser extent in the direction of the track longitudinal axis than in the two rail supporting longitudinal segments (Bl, B2) of the railroad tie. Key-feature II according to the invention is based on the insight of the inventor that therewith the bending stiffness of the railroad tie in the two rail supporting longitudinal segments (Bl, B2) is relatively larger than in the intermediate longitudinal segment (C), and this is the case in a reliable and well-balanced manner, which has a favourable influence on limiting the bending of the railroad tie. Therewith the second tie balancing ratio has a further favourable influence on preventing center bounding and end bounding.According to the third key-feature III the “footprint surface area” of the whole railroad tie or of a part of the railroad tie, as used in the first tie balancing ratio and the second tie balancing ratio, is defined as the surface area of said vertical bottom view of the whole railroad tie or of the part of the railroad tie, respectively. This key-feature III is based on the insight of the inventor that in thecourse of time a railroad tie sinks ever further into the underlying ballast bed, and that in the course of time all parts of said vertical bottom view of the railroad tie contribute to the surface area of downward facing contact surface of the railroad tie with an underlying ballast bed.Thus the above-mentioned key features I, II and III provide a reliable solution for preventing center bounding of railroad ties in railroads, whereby considerable cost savings can be obtained related to maintenance of railroads and energy consumption of trains. As a result of the sophisticated balancing principles according to the invention, the invention additionally contributes to minimizing the amount of material of the railroad ties for minimizing the cost price of the railroad ties. It is remarked that the above-mentioned key-feature II requires that according to the invention the railroad tie has to be designed with shapes which deviate from a three-dimensionally fully straight rectangular railroad tie. In relation thereto it is further remarked that it is possible to produce a plastic railroad tie according to the invention with a tailor-made complex three-dimensional geometry by means of a tailor-made mould, whereby the railroad tie can be produced in large numbers with favourable cost price for a certain railroad.The present invention can be applied with said advantages for railroads, wherein said centre-to-centre distance (M) between the first rail centre line and the second rail centre line is between 1050 mm and 1750 mm, which is the case for the vast majority of the various railroads worldwide.In a preferable embodiment of the invention the first tie balancing ratio is between 0.455 and 0.495, and more preferably between 0.460 and 0.490.In a further preferable embodiment of the invention the second tie balancing ratio is between 2.7 and 9.0, more preferably between 2.9 and 8.0, and yet more preferably between 3.1 and 7.0.In a further preferable embodiment according to the invention the railroad tie comprises first rail fastening provisions and second rail fastening provisions for fastening said first rail and said second rail, respectively, on top of the railroad tie, wherein the first rail fastening provisions and the second rail fastening provisions are determining said mutual centre-to-centre distance (M) of said first rail and said second rail. Such rail fastening provisions may for example comprise: fastening elements, such as tie plates; and / or recesses, such as bore holes in the body of the railroad tie; and / or markings / indications at the railroad tie, such asmarkings / indications which determine the location of fastening provisions relative to the body of the railroad tie.In the following, the invention is further elucidated on the basis of a few non-limiting examples and with reference to the schematic figures in the appended drawing.Fig. 1A shows a first plastic railroad tie, not being part of the present invention, wherein the first railroad tie rests on ballast of a ballast bed while the first railroad tie is loaded by a passing train.Fig. IB shows the situation of Fig. 1A again, however, wherein this time the train has passed over the first railroad tie.Fig. 1C shows a second plastic railroad tie, not being part of the present invention, wherein the second railroad tie rests on ballast of a ballast bed while the second railroad tie is loaded by a passing train.Fig. ID shows the situation of Fig. 1C again, however, wherein this time the train has passed over the second railroad tie.Fig. 2 shows an example of an embodiment of a railroad according to the invention, in a transverse cross-section perpendicular to a the track longitudinal axis of the railroad.Fig. 3 shows a part of the railroad of Fig. 2 again, however, this time in a perspective view on the top of the railroad tie of the railroad.Fig. 4 shows the railroad tie of Figs. 2-3 in a similar view as in Fig. 3, however, this time in a perspective view on the bottom of the railroad tie.Fig. 5 shows a vertical bottom view of the railroad tie of Figs. 2-4, as seen in said horizontal reference condition of the railroad tie.Fig. 6 shows, in a similar situation as in Fig. 3, an example of an alternative embodiment of a railroad according to the invention in that the railroad tie of Fig. 6 is an alternative embodiment as compared to the railroad tie of Fig. 3, and wherein Fig. 6 shows a perspective view on the top of the railroad tie.Fig. 7 shows the railroad tie of Fig. 6 in a similar view as in Fig. 6, however, this time in a perspective view on the bottom of the railroad tie.Figs. 1A-1D have already been discussed in the introductory description herein-above.The reference signs used in the above-mentioned Figs. 2-7 are referring to the above-mentioned parts and aspects of the invention, as well as to related parts and aspects, in the following manner.Based on the above introductory description, including the above brief description of Figs. 2-7, and based on the above explanation of the reference signs used in Figs. 2-7, the shown embodiments of Figs. 2-7 are largely and readily self- explanatory. The following extra explanations are given. Now reference is made to the example of Figs. 2-5, and more particularly toFig. 5 thereof. Fig. 5 shows a vertical bottom view of the railroad tie 3 as considered in said horizontal reference condition of the railroad tie 3. In Fig. 5 also thepositions of the first rail center line 31 and the second rail center line 32 are indicated. Fig. 5 shows that the first rail supporting longitudinal segment Bl, the second rail supporting longitudinal segment B2 and the intermediate longitudinal segment C each have a length, measured along the tie longitudinal axis 4, equal to 50% of the centre-to-centre distance M. Furthermore it appears from Fig. 5 that the overall tie length L of the railroad tie 3 is larger than 150% of the centre-to-centre distance M. Since according to the invention a footprint surface area of the whole railroad tie or of a part of the railroad tie is defined as the surface area of said vertical bottom view of the whole railroad tie or of the part of the railroad tie, respectively, it can be readily appreciated by Fig. 5 how the first tie balancing ratio and the second tie balancing ratio of the shown example of Figs. 2-5 are calculated. In the shown example of Figs. 2-5 the first tie balancing ratio has a value of 0.479 and the second tie balancing ratio has a value of 3.82.Thanks to the fact that the first tie balancing ratio has a favourable value of 0.479 according to the invention, the railroad tie 3 can be supported by the ballast bed 2 in a reliable and well-balanced manner both in the two longitudinal end segments Al and A2 and in the intermediate longitudinal segment C, i.e. while it is prevented that the railroad tie 3 would substantially rest with the intermediate longitudinal segment C on the ballast bed (center bounding) and while it is prevented that the railroad tie would substantially rest with the two longitudinal end segments Al and A2 on the ballast bed (“end bounding”). In other words, center bounding and end bounding are prevented.The second tie balancing ratio having a favourable value of 3.82, which is obtained in that the railroad tie 3 has more underlying contact surface with the ballast bed 2 in the two rail supporting longitudinal segments Bl and B2 than in the intermediate longitudinal segment C, has a favourable influence on limiting the bending of the railroad tie. Therewith the second tie balancing ratio has a further favourable influence on preventing center bounding and end bounding.It is remarked that in the shown example of Figs. 2-5 the bottom 24 of the railroad tie 3 is a fully straight plane without elevations, and that this fully straight bottom 24 in this example is identical to the vertical bottom view, shown in Fig. 5, of the whole railroad tie 3. However, the invention is not at all limited to situations in which a railroad tie has a fully straight bottom which is identical to the shape of such a vertical bottom view.For the purpose of comparison, it is now referred to the railroad tie shown in the above-mentioned document WO 2011 / 103284 Al, see Figs. 1-4 of WO 2011 / 103284 Al. In this known railroad tie a midsection of the bottom of the railroad tie has a round shape, which is best seen in Fig. 3 of WO 2011 / 103284 Al. However, in vertical bottom view this known railroad tie has a fully rectangular shape according to the rectangle of Fig. 1 of WO 2011 / 103284 Al. Should this railroad tie of WO 2011 / 103284 Al be used in a railroad with a certain overall tie length and with a certain centre-to-centre distance (in the sense of the present invention) in such manner that the overall tie length would have a value larger than or equal to 150% of the centre-to-centre distance, than the railroad tie of WO 2011 / 103284 Al would have a second tie balancing ratio of 2.00 in the sense of the present invention. Hence, this value 2.00 is outside the favourable range of the second tie balancing ratio according to the invention, which is in agreement with the above-mentioned drawback of the embodiment of WO 2011 / 103284 Al that, due to the fact that the railroad tie in the course of time sinks further into the ballast, the bottom width by which the round midsection of the railroad tie of WO 2011 / 103284 Al rests on the ballast becomes ever larger in the course of time, and that thereby the preventing of center bounding will be undone more and more in the course of time.Reference is now made to the example of Figs. 6-7, which show an alternative embodiment of a railroad 101 according to the invention in that the railroad tie 103 of Figs. 6-7 has an alternative shape relative to the railroad tie 3 of Figs. 2-5. The railroad tie 103 has been designed to have a plurality of toes, which serve to provide the railroad tie 103 with a larger sideward stability in a ballast bed than the railroad tie 3. The railroad tie 103 has also been designed to have favourable values, according to the invention, of the first tie balancing ratio and the second tie balancing ratio, wherein these favourable values do not differ much from the values of the railroad tie 3.It is noted that the above-mentioned examples of embodiments do not limit the invention and that within the scope of the appended claims various alternatives are possible. For example, the railroad tie may be manufactured from various kinds of plastic, which may or may not be recycled, and may or may not be provided with various kinds of additions. For instance, the plastic may be a polyethylene. Also, the reinforcement constructions embedded in the plastic may be of various kinds ofmaterials, such as various metals or metal alloys, steel, etcetera, but also various other kinds of construction materials, such as various construction plastics which have a higher lateral stiffness than the plastic in which the reinforcement constructions are embedded. Other variants or modifications, however, are also possible within the scope of the invention as defined in the appended claims.

Claims

CLAIMS1. A railroad (1) comprising:- a ballast bed (2),- a railroad tie (3), which is manufactured from at least plastic and which is resting at and / or in the ballast bed, and- a first rail (11) and a second rail (12) which are fastened on top of the railroad tie, wherein the railroad tie (3) has a tie longitudinal axis (4) and the railroad (1) has a track longitudinal axis (5), and wherein the track longitudinal axis (5) is substantially perpendicular to the tie longitudinal axis (4), and wherein a horizontal reference condition of the railroad tie is defined to correspond to an imaginary orientation of the railroad tie together with the first rail and the second rail, said imaginary orientation being such that each of the tie longitudinal axis and the track longitudinal axis extends horizontally, and wherein, as considered in said horizontal reference condition of the railroad tie:- the railroad tie (3) extends along the tie longitudinal axis (4) from a first tie end (21) to a second tie end (22),- the first rail (11) and the second rail (12) in a vertical top view have a first rail centre fine (31) and a second rail centre line (32), respectively, which are parallel to the track longitudinal axis (5), wherein the first rail centre line and the second rail centre line have a centre-to-centre distance (M) relative to one another,- an overall tie length (L) of the railroad tie (3), said overall tie length (L) being measured along the tie longitudinal axis (4) between the first tie end (21) and the second tie end (22), is larger than or equal to 150% of said centre-to-centre distance (M) between the first rail centre line and the second rail centre line, with the characterizing definitions. that, as considered in said horizontal reference condition of the railroad tie and as considered in a vertical bottom view of the railroad tie:- a footprint surface area of the whole railroad tie (3) or of a part of therailroad tie is defined as the surface area of said vertical bottom view of the whole railroad tie or of the part of the railroad tie, respectively,- a first rail supporting longitudinal segment (Bl) of the railroad tie (3) is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis (4), extend between two first longitudinal positions, which are situated along the tie longitudinal axis on two mutually opposite sides, respectively, of the first rail centre line (31), wherein each of the two first longitudinal positions has a distance to the first rail centre line (31) equal to 25% of said centre-to-centre distance (M),- a second rail supporting longitudinal segment (B2) of the railroad tie (3) is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis (4), extend between two second longitudinal positions, which are situated along the tie longitudinal axis on two mutually opposite sides, respectively, of the second rail centre line (32), wherein each of the two second longitudinal positions has a distance to the second rail centre line equal to 25% of said centre-to-centre distance (M),- an intermediate longitudinal segment (C) of the railroad tie (3) is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis (4), extend between the first rail supporting longitudinal segment (Bl) and the second rail supporting longitudinal segment (B2),- a first longitudinal end segment (Al) of the railroad tie (3) is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis (4), extend between the first tie end (21) and the first rail centre line (31),- a second longitudinal end segment (A2) of the railroad tie (3) is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis (4), extend between the second tie end (22) and the second rail centre line (32), and with the characterizing features, that a first tie balancing ratio is between 0.45 and 0.50, wherein the first tie balancing ratio is defined as a quotient, of which the numerator is equal to the sum of the footprint surface areas of the first longitudinal end segment (Al) and the second longitudinal end segment (A2), respectively, and of which the denominator is equal to the footprint surface area of the whole railroad tie (3), andthat a second tie balancing ratio is between 2.5 and 10.0, wherein the second tie balancing ratio is defined as a quotient, of which the numerator is equal to the sum of the footprint surface areas of the first rail supporting longitudinal segment (Bl) and the second rail supporting longitudinal segment (B2), respectively, and of which the denominator is equal to the footprint surface area of the intermediate longitudinal segment (C).

2. The railroad (1) according to claim 1, wherein the first tie balancing ratio is between 0.455 and 0.495, and more preferably between 0.460 and 0.490.

3. The railroad (1) according to claim 1 or 2, wherein the second tie balancing ratio is between 2.7 and 9.0, more preferably between 2.9 and 8.0, and yet more preferably between 3.1 and 7.0.

4. The railroad (1) according to any one of the preceding claims, wherein said centre-to-centre distance (M) between the first rail centre fine (31) and the second rail centre line (32) is between 1050 mm and 1750 mm.

5. A method of building a railroad (1) according to any one of the claims 1-4, comprising fastening said first rail (11) and said second rail (12) of said railroad on top of said railroad tie (3) of said railroad.

6. A railroad tie (3) for use in a railroad (1), wherein:- the railroad tie is manufactured from at least plastic,- the railroad tie has a tie longitudinal axis (4) and the railroad tie extends along the tie longitudinal axis from a first tie end (21) to a second tie end (22),- the railroad tie has a horizontal reference condition, in which each of the tie longitudinal axis (4) and a track longitudinal axis (5) of an imaginary railroad (1) extends horizontally, the track longitudinal axis (5) extending perpendicularly to the tie longitudinal axis (4), and in which an imaginary first rail (11) and an imaginary second rail (12) of the railroad are fastenable on top of the railroad tie (3), in such manner that:• the first rail (11) and the second rail (12) in a vertical top view thereof have a first rail centre fine (31) and a second rail centre line (32), respectively, which are parallel to the track longitudinal axis (5),• the first rail centre fine (31) and the second rail centre line (32) have a mutual centre-to-centre distance (M) which is between 1050 mm and 1750 mm, and• an overall tie length (L) of the railroad tie (3), measured along the tie longitudinal axis (4) between the first tie end (21) and the second tie end (22), is larger than or equal to 150% of said centre-to-centre distance (M) between the first rail centre line and the second rail centre line, with the characterizing definitions, that, as considered in said horizontal reference condition of the railroad tie and as considered in a vertical bottom view of the railroad tie:- a footprint surface area of the whole railroad tie (3) or of a part of the railroad tie is defined as the surface area of said vertical bottom view of the whole railroad tie or of the part of the railroad tie, respectively,- a first rail supporting longitudinal segment (Bl) of the railroad tie (3) is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis (4), extend between two first longitudinal positions, which are situated along the tie longitudinal axis on two mutually opposite sides, respectively, of the first rail centre line (31), wherein each of the two first longitudinal positions has a distance to the first rail centre fine (31) equal to 25% of said centre-to-centre distance (M),- second rail supporting longitudinal segment (B2) of the railroad tie (3) is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis (4), extend between two second longitudinal positions, which are situated along the tie longitudinal axis on two mutually opposite sides, respectively, of the second rail centre line (32), wherein each of the two second longitudinal positions has a distance to the second rail centre line equal to 25% of said centre-to-centre distance (M),- an intermediate longitudinal segment (C) of the railroad tie (3) is defined as comprising all parts of the railroad tie, which, considered along the tielongitudinal axis (4), extend between the first rail supporting longitudinal segment (Bl) and the second rail supporting longitudinal segment (B2),- a first longitudinal end segment (Al) of the railroad tie (3) is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis (4), extend between the first tie end (21) and the first rail centre line (31),- a second longitudinal end segment (A2) of the railroad tie (3) is defined as comprising all parts of the railroad tie, which, considered along the tie longitudinal axis (4), extend between the second tie end (22) and the second rail centre line (32), and with the characterizing features, that said first rail (11) and said second rail (12) being fastenable on top of the railroad tie (3), furthermore is such that: a first tie balancing ratio is between 0.45 and 0.50, wherein the first tie balancing ratio is defined as a quotient, of which the numerator is equal to the sum of the footprint surface areas of the first longitudinal end segment (Al) and the second longitudinal end segment (A2), respectively, and of which the denominator is equal to the footprint surface area of the whole railroad tie (3), and a second tie balancing ratio is between 2.5 and 10.0, wherein the second tie balancing ratio is defined as a quotient, of which the numerator is equal to the sum of the footprint surface areas of the first rail supporting longitudinal segment (Bl) and the second rail supporting longitudinal segment (B2), respectively, and of which the denominator is equal to the footprint surface area of the intermediate longitudinal segment (C).

7. The railroad tie (3) according to claim 6, wherein the first tie balancing ratio is between 0.455 and 0.495, and more preferably between 0.460 and 0.490.

8. The railroad tie (3) according to claim 6 or 7, wherein the second tie balancing ratio is between 2.7 and 9.0, more preferably between 2.9 and 8.0, and yet more preferably between 3.1 and 7.0.

9. The railroad tie (3) according to any one of the claims 6-8, wherein the railroad tie comprises first rail fastening provisions (41) and second rail fasteningprovisions (42) for fastening said first rail (11) and said second rail (12), respectively, on top of the railroad tie (3), wherein the first rail fastening provisions and the second rail fastening provisions are determining said mutual centre-to- centre distance (M) of said first rail (11) and said second rail (12).

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