RAIL ASSEMBLY AND COMPOSITE POLYMER CROSSTIES THEREFOR

Info

Publication number: 20170058460
Type: Application
Filed: Nov 14, 2016
Publication Date: Mar 2, 2017
Inventors: Brian ABRAMSON (Brampton), James R. INGLIS (Brampton)
Application Number: 15/351,306

Abstract

Disclosed are different embodiments of a railway tie assembly for securing a rail along a railway track. In one embodiment, the assembly comprises a plurality of composite polymer crossties fabricated from a composition comprising an asphaltic component, a polymeric composition component and a strengthening agent; and a pair of rail clips for securing the rail across each of said composite polymer crossties, wherein each of the rail clips comprises a rail-engagement portion configured to engage a corresponding railseat, and an anchoring portion to be anchored to a given crosstie and cooperate with the rail-engagement portion to secure the corresponding railseat against a load-bearing surface of the given crosstie.

Description

Description

RELATED APPLICATION

The present application is a U.S. Continuation application which claims benefit of priority to International Patent Application serial number PCT/CA2015/050392 entitled “Rail Assembly and Composite Polymer Crossties Therefor”, filed May 5, 2015 which in turn which claims benefit of priority to Canadian Patent Application serial number 2,852,525 entitled “Rail Assembly and Composite Polymer Crossties Therefor”, filed May 15, 2014, the subject matter of which are herein incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to rail assemblies, and in particular, to a rail assembly and composite polymer crossties therefor.

BACKGROUND

Conventional wooden timber crossties and concrete railway crossties coupling systems require that the railway rails be coupled to the crosstie such that the two railway rails maintain a specific spacing corresponding to the wheel spacing of wheels coupled to an axle of a railway car. A rail is typically coupled to the crosstie by way of two or more rail clips which are coupled to the crosstie by way of an intervening tie plate fastened to the crosstie using spikes or screw-type spikes. A portion of the clip correspondingly applies pressure to the railseat to maintain the rail against the crosstie.

The compressive forces exerted by a train as it passes over a given railway crosstie are known to cause degradation in the railway crosstie. For example, in the case of wooden crossties, the compressive force of the base (railseat) of the railway rail, with the tie plate thereunder, against the crosstie as a train passes thereover, over time causes the wood fibres of the crosstie to breakdown. Therefore the railway rail, or the tie plate in instances where one is present, cuts into the wood and a gap is formed between the bottom of the railway rail and the crosstie. Similarly in the case of concrete crossties, the compressive forces cause the concrete and/or a compression pad (“also termed a cushion mat”) under the tie plate to wear under the railway rail and a gap to form. Repeated train travel along the rails causes the rail to flex into the created gap and impact the crosstie, thus causing further breakdown of the crosstie and the gap to increase in size. With concrete crossties, the impact of the rail across the gaps may cause the concrete crosstie to fracture, leading to catastrophic failure.

Also, as the gap increases, the constant flexing and retraction of the rail as a train travels thereover is known to cause the fasteners coupling the rail or tie plate to the crosstie to loosen. This creates a situation where the gap is further increased and/or the rail becomes uncoupled from the crosstie. In such cases where uncoupling occurs, if the crosstie has not suffered a failure where it needs to be replaced, the crosstie will need to be “re-spiked” which is time-consuming and costly. During re-spiking, the original spike hole must be plugged and a new spike bore made. The rail can then again be coupled to the crosstie.

In order to reduce the incidence of catastrophic failure, in both the case of wooden crossties and concrete crossties, maintenance crews must be deployed to survey railway lines for developing gaps between railway rails and corresponding crossties. Once a gap is detected the maintenance crew must undertake to tighten the fasteners and secure the rail against the crosstie. However, by such a time, significant damage may have already been done to the crosstie. For example, in the case of a wooden crosstie, once a gap of from about ⅜″ to about ½″ is developed, the rail must be tightened.

In order to mitigate a gap developing, the industry has accepted the use of surface area-increasing force-distributing plates and/or cushion mats being placed between the bottom of the rail and the crosstie. For example, resilient cushioning mats, or cushion mats are used in conjunction with concrete crossties to minimize abrasion of the railseat area, and reduce impact and vibration effects on the track structure in an attempt to minimize gaps from forming. In the case of wooden crossties, a surface area-increasing force-distributing steel plate is often used between the railseat and the crosstie to increase the surface area and distribute the compressive forces from the train over a larger area of the crosstie. This aids to reduce the wood fibres immediately under the rail from breaking down as rapidly as if the surface area-increasing force-distributing steel plate were not present. However, it is known that with both of these approaches, the crossties still breakdown by way of the compressive forces, and/or abrasion, and the fasteners retract from their respective seats resulting in a gap between the bottom of the rail and the crossties still forming. Therefore, the use of cushion mats and surface area-increasing force-distributing steel plates serve to increase the life a crosstie, yet significant maintenance to tighten the rails to the crossties is still required. Furthermore, the required use of the cushion mats and surface area-increasing force-distributing steel plates increases the unit cost of each crosstie installation.

United States Patent Application Publication number US 2006/0226247 A1, published Oct. 12, 2006 to Abramson, et al. and entitled “Railway Ties and Structural Elements” describes a composite structural element such as a railway tie made from an asphaltic component and a fibre reinforced plastics component.

U.S. Pat. No. 8,252,216, issued Aug. 28, 2012 to Abramson, et al. and entitled “Method for the Production of Railway Ties” describes a method for producing composite railway ties from two co-extruded compositions where each composition comprises an asphaltic component, a polymeric component and a strengthening agent. The strengthening agent may be a fibre and is preferably a glass fibre.

This background information is provided to reveal information believed by the applicant to be of possible relevance. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art.

SUMMARY

The following presents a simplified summary of the general inventive concept(s) described herein to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the invention. It is not intended to restrict key or critical elements of the invention or to delineate the scope of the invention beyond that which is explicitly or implicitly described by the following description and claims.

There is a need in the industry to provide a system including a crosstie which is more resistant to compressive forces exerted by a passing train and one which improves fastener retention. Also, it would be advantageous to provide a system which can meet the abovementioned needs, as well as other needs, with fewer parts, lower overall material costs, installation costs and/or lifetime maintenance costs. Lower lifetime maintenance cost may, for example, be realized by less required maintenance over the lifetime of a given crosstie installation.

It has been surprisingly discovered that using a system such as that described herein which makes use of composite polymer crossties improves the coupling of railway rails to crossties over the conventionally used wood or concrete crosstie systems. For example, in various testing models employed it was shown that using the system disclosed herein, rail/plate area compression testing of the crossties returned values far exceeding industry requirements, and embedded screw-spike/threaded insert pull-out testing also returned values far exceeding the industry requirements and that which is conventionally expected for wooden, concrete and other composite crossties.

In accordance with one aspect, there is provided a railway tie assembly for securing a rail along a railway track, the assembly comprising: a plurality of composite polymer crossties fabricated from a composition comprising an asphaltic component, a polymeric composition component and a strengthening agent; and a pair of rail clips for securing the rail across each of said composite polymer crossties, wherein each of said rail clips comprises a rail-engagement portion configured to engage a corresponding railseat, and an anchoring portion to be anchored within a given crosstie and cooperate with said rail-engagement portion, once installed, to secure said corresponding railseat against a load-bearing surface of said given crosstie.

In accordance with one such aspect, an anchoring of the rail to said crossties maintains or strengthens the anchoring portion's gripping power to the crosstie under use by virtue of said composition.

In accordance with another aspect, there is provided a railway track comprising: a plurality of composite polymer crossties fabricated from a composition comprising an asphaltic component, a polymeric composition component and a strengthening agent, wherein said crossties are disposed at regular intervals along the railway track; one or more rails each composed of rail segments juxtaposed end-to-end along the railway track, a respective railseat thereof disposed crosswise upon a respective load-bearing surface of each of said crossties; and respective pairs of rail clips securing respective ones of said rail segments to each of said composite polymer crossties, wherein each of said rail clips comprises a rail-engagement portion engaging a corresponding railseat, and an anchoring portion anchored to a given composite crosstie and cooperating with said rail-engagement portion to secure said corresponding railseat against said respective load-bearing surface of said given crosstie.

In accordance with one such aspect, an anchoring of said rail segments to said crossties is maintained or strengthened under use by virtue of said composition.

Other aims, objects, advantages and features of the invention will become more apparent upon reading of the following non-restrictive description of specific embodiments thereof, given by way of example only with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE FIGURES

In order that the invention may be better understood, exemplary embodiments will now be described by way of example only, with references to the accompanying drawings, wherein:

FIG. 1a is a top perspective view of a portion of an exemplary composite polymer crosstie having a railseat receiving rectangular channel formed therein, in accordance with one embodiment;

FIG. 1b is a top perspective view of a portion of a composite polymer crosstie having an exemplary railseat and abrasion guard receiving rectangular channel formed therein, as shown in ghost lines, in accordance with one embodiment;

FIG. 1c is a front elevation view of the composite polymer crosstie portion of FIG. 1a showing a cross-sectional view of a rail section mounted thereon with a railseat thereof received in the rectangular channel;

FIG. 2a is a top plan view of the composite polymer crosstie portion of FIG. 1a showing a rail portion coupled thereto using exemplary inner and outer rail clips and with a portion of the railseat received in the rectangular channel, in accordance with one embodiment;

FIG. 2b is a top plan view of the composite polymer crosstie section of FIG. 1b showing a rail portion coupled thereto using exemplary inner and outer rail clips and with a portion of the railseat and an exemplary abrasion guard received in the rectangular channel;

FIG. 3a is a top plan view of a portion of railway tracks showing a plurality of the composite polymer crossties of FIG. 1a with two rail sections coupled thereto using exemplary inner and outer rail clips and with portions of the respective railseats received in respective rectangular channels;

FIG. 3b is an enlarged top perspective view of a portion of the rail installation of FIG. 3a showing inner and outer shims in communication with respective inner and outer rail clips and further showing in cross section the railseat received in the rectangular channel, in accordance with one embodiment;

FIG. 4 is a side view of an alternative rail installation similar to that shown in FIG. 3b showing inner and outer rail clips coupled to the composite polymer crosstie using fasteners bored into the composite polymer crosstie (shown in ghost lines), and further showing an abrasion guard received along an outermost sidewall of the rectangular channel;

FIG. 5 is a side view of an alternative rail installation similar to that shown in FIG. 4, comprising an extended abrasion guard having a flange portion extending along a top surface of the composite polymer crosstie and along a bottom load-bearing surface of the rectangular channel;

FIG. 6 is a side view of an alternative rail installation similar to that shown in FIG. 5, comprising a further extended abrasion guard having an inner rectangular channel sidewall portion;

FIG. 7 is a top perspective view of a partially assembled rail assembly composed of an exemplary composite polymer crosstie having a railseat-receiving wedge formed therein and opposed rail clip anchoring structures fastened on either side thereof to directly or indirectly restrict a lateral travel of a railseat subsequently disposed therebetween;

FIG. 8 is a top perspective view of the assembly of FIG. 7, further showing respective rail-engaging portions slidingly received within corresponding anchoring portions of the anchoring structures in a pre-assembled configuration, a rail received inclined in the railseat-receiving wedge, and respective collars disposed about the anchoring portions to directly restrict a lateral travel of the railseat resting therebetween; and

FIG. 9 is an enlarged perspective view of the assembly of FIG. 8 once fully assembled, showing a sliding engagement of the rail-engaging portion upon the railseat.

DETAILED DESCRIPTION

With reference to the disclosure herein and the appended figures, a rail assembly and composite polymer crossties therefor will now be described in accordance with various embodiments of the invention.

With reference to FIGS. 1a, 1b and 1c, and in accordance with one embodiment, an exemplary composite polymer crosstie 12 is shown for use in a rail assembly as contemplated herein and described below (e.g. see assembly 10 of FIG. 2a). In this embodiment, the composite polymer crosstie 12 has a rectangular channel 14 formed or cut in a top surface 16 thereof for receiving therein a base portion or railseat 18 of a railway rail 20 as shown in FIG. 1c. In some embodiments the rectangular channel 14 is dimensioned across distance A to substantially match the width of the railseat 18. However, in other embodiments shown for example in FIGS. 4 to 6, the rectangular channel 14 may be dimensioned across A to also fit an abrasion guard 22 along with the railseat 18. In these embodiments, the rectangular channel is further dimensioned to have a depth B suitable to accommodate the railseat 18, and optionally different embodiments of the abrasion guard 22 as shown in FIGS. 4 to 6. An exemplary depth B for use with the various embodiments of abrasion guards 22 is also shown in ghost in FIG. 1b relative to the rectangular channel 14 for use in embodiments devoid of an abrasion guard 22. Accordingly, the rectangular channel 14 serves to inhibit or prevent lateral movement of the railway rail 20 relative to the crosstie 12 during use.

Turning now to the rectangular channel 14, a bottom load-bearing surface 24 of the rectangular channel 14, in some embodiments, is provided such that it is parallel with the composite polymer crosstie 12 top surface 16. However, in some embodiments the railhead 26 may be inwardly inclined or canted (i.e. toward one another in a two rail assembly) as shown, for example, in FIGS. 1c, and 4 to 6 at angle θ. Accordingly, the bottom surface 24 may be provided at an angle which is inclined towards an outer edge 28 of the composite polymer crosstie 12. The cant angle θ to the rail 20, and thus the railhead 26 resultant from the outward incline of the bottom surface 24, is shown in the figures relative to vertical at θ. The cant to the railhead 26 may be, for example, from about 1:40 to about 1:10 dependent on that required by the specific application of the rail assembly and composite polymer crossties 12 used therefor. In some examples, the cant is provided at about 1:20. The cants noted herein should not be considered to be limiting and are provided for exemplary purposes, only. One of skill in the art would readily understand which cants may be required for specific applications. In other embodiments the bottom surface 24 may be provided as being parallel with the top surface 16 and the abrasion guard 22, in embodiments with an abrasion guard bottom portion 22a, as shown in FIGS. 5 and 6, for example, may be fashioned to provide the desired cant to the railhead 26. Therefore, in such embodiments the abrasion guard base portion 22a may be wedge-shaped to provide the outward incline as noted above.

With reference now to FIGS. 3a and 3b, and in accordance with one embodiment, a plurality of composite polymer crossties 12 are provided to have coupled thereto and maintain two rails 20 at a desired spacing. FIG. 3b shows an enlarged perspective view of the assembly 10 in relation to a cut through section of one of the rails 20. The railseat 18 is laid into a correspondingly dimensioned rectangular channel 14 such that the railseat 18 fits substantially snuggly in the rectangular channel 14. An inner rail clip 30 and an outer rail clip 32 are provided to maintain the railseat 18 in the rectangular channel 14 and thus couple the rail 20 to the composite polymer crosstie 12.

Both the inner rail clip 30 and the outer rail clip 32 are provided in the embodiments described herein as having a substantially “W” shape, as can be seen in the figures. Furthermore, as can be seen in FIGS. 3b to 6, for example, the inner rail clip 30 and the outer rail clip 32 have an arced profile which aids to provide resiliency against vibrations from a train passing along the rails and to maintain the rail 20 in a coupled arrangement with the composite polymer crossties 12. Such resiliency provided by a formed arc of the inner and outer rail clips 30 and 32 allows a degree of bending of the rail clips under load and resists fracturing of the rail clips with repeated vibrations and train travel. Should the inner rail clip 30 and the outer rail clip 32 not be provided with some degree of resiliency, they may have a tendency to prematurely crack and fail.

The inner rail clip 30 has a shim contacting outer portion 30a, a rail contacting inner portion 30b (e.g. rail-engagement portion) and a center region (e.g. anchoring structure) having a fastener passage 30c, as shown, for example in FIG. 2a. Similarly, the outer rail clip 32, also as shown in FIG. 2a, has a shim contacting outer portion 32a, a rail contacting inner portion 32b and a center portion having a fastener passage 32c.

As shown in the figures, a fastener 34 is passed through the fastener passages 30c and 32c located in the center portion of the respective rail clips 30 and 32. The faster 34 is inserted and maintained in a bore 36 of the composite polymer crosstie 12 as shown, for example, in FIGS. 4 to 6. In some embodiments, such as the ones provided in the figures, the fastener 34 may be provided as a screwspike fastener having helical threads as is commercially available and known in the art. In other embodiments (not shown), the fastener 34 may be provided as an impact force-driven spike which is devoid of helical threads. The general shape of the inner and outer rail clips 30 and 32 should not be limited specifically to a “W” shape as other rail clips, such as that described below with reference to FIGS. 7 to 9 in accordance with another illustrative embodiment, may be readily considered herein without departing from the general scope and nature of the present disclosure. The “W” shape is noted herein as an example, only, other shapes for the inner and outer rail clips 30 and 32 may be suitable. For example, such a shape for one or both of the inner and outer rail clips 30 and 32 may be a “V” shape, a “U” shape, a “J” shape, an “N” shape, and so on.

With reference to FIG. 3b, the assembly 10 also includes shims 38 and 40, which, in use, are respectively placed on the top surface 16 of the composite polymer crossties 12 under the shim contacting outer portions 30a and 32a of the inner rail clip 30 and the outer rail clip 32 respectively. The fasteners are then inserted and driven into the composite polymer crossties 12 as shown in the figures, passing through the respective inner and outer rail clip fastener passages 30c and 32c. Therefore, in use, the rail contacting inner portions 30b and 32b of the respective inner and outer rail clips 30 and 32, with the fasteners 34 in place maintain, the railseat 18 in the rectangular channel 14. The inner shim 38 and the outer shim 40 are provided to elevate the shim contacting outer portions 30a and 32a and thus increase the toe pressure of the rail contacting inner portions 30b and 32b on the respective areas of the railseat 18, as shown in particular in FIGS. 3b to 6. Additionally, as shown in the aforementioned figures, in some embodiments, it is preferable to have the outer shim 40 be of a greater height or thickness as compared to the inner shim 38 so as to increase the toe pressure applied to the railseat 18 along the outer side thereof (i.e. in a two rail system). Such increased toe pressure of the outer rail clip 32 compared to the inner rail clip 30 may be used, for example, in applications where the railhead 26 is inwardly inclined as shown in FIGS. 4 to 6 by way of an outwardly inclined rectangular channel bottom surface 24, as discussed above. The increased toe pressure provided by the outer shim 40 having an increased thickness versus the inner shim 38, may also aid to maintain the railseat 18 in the rectangular channel 14 and counter the downward forces applied to the railhead 26 by a train passing thereover. In embodiments where the railhead 26 is inwardly inclined, as shown in FIGS. 4 to 6, for example, should sufficient toe pressure not be applied at the rail contacting inner portion 32b of the outer rail clip 32, the rail 20 may have a tendency to rotate inward and lead to failure of the system. In some embodiments, the toe pressure of the rail contacting inner portions 30b and 32b on the respective areas of the railseat 18 is provided in a range from about 500 psi to about 10,000 psi by way of tightening corresponding fastener 34 and the interaction of the shim contacting outer portions 30a and 32a with shims 38 and 40, respectively. Additionally, for example, the dimensions of shims 38 and 40 may also be varied in order to achieve the desired toe pressures. In preferred embodiments the toe pressure of the rail contacting inner portions 30b and 32b is provided in a range from about 2,000 psi to about 3,200 psi. Various different toe pressures may be required depending on the application of the assembly defined herein so as to couple the railway rail 20 to the crosstie 12 in different environments and may be readily determined by one of skill in the art.

As discussed below in more detail with respect to the testing of the composite polymer crossties 12 of the instant disclosure, although the composite polymer crossties 12 of the system 10 as disclosed herein are more resistant to abrasion and compressive forces compared to conventionally used wooden crossties, in some instance it may be desirable for the system 10 to include an abrasion guard 22. Various embodiments and orientations of the abrasion guard 22 are discussed above in relation to their installation relative the railseat 18 and the rectangular channel 14. More specifically, the abrasion guard 22 in one embodiment, as shown FIG. 4, may be placed in the rectangular channel 14 along an outermost side wall 42 of the rectangular channel 14. In such an embodiment, the rectangular channel 14 along distance A is made wider so as to accommodate the width of the railseat 18 plus the abrasion guard 22. For example, with an abrasion guard 22 fashioned and employed as shown in FIG. 4, the forces exerted on the rail 20 by a train passing thereover and applied both downward and in the direction towards the outer edge 28 of the composite polymer crosstie 12 are absorbed by the abrasion guard 22 so as to reduce damage/wear to the composite polymer crosstie 12 along the outermost side wall 42 of the rectangular channel 14. Additionally, such an abrasion guard 22 may also aid to afford protection against cracking or fracturing to the composite polymer crosstie 12 starting at the intersection of the outermost side wall 42 and the rectangular channel bottom wall 24 as well as damage to the outermost side wall 42 itself owing to forces resultant from trains repeatedly passing along rail 20.

FIG. 5 shows another embodiment of the abrasion guard 22 wherein an abrasion guard base portion or flange 22a is provided. In such an embodiment the abrasion guard 22 is fashioned to line the outermost sidewall 42 as well as the bottom wall 24 of the rectangular channel 14. The railseat 18 then rests on the abrasion guard base portion 22a, in use. As shown in FIG. 6 with respect to another embodiment of the abrasion guard 22, an innermost sidewall 46 of the rectangular channel 14 is also lined with a portion of the abrasion guard 22, namely an inner rectangular channel sidewall abrasion guard portion 44. Therefore, in the embodiment shown in FIG. 6, the abrasion guard 22 is fashioned to form a substantially “U-shaped” member in profile, which lines the interior surfaces of the rectangular channel 14.

In other embodiments (not shown), two independent abrasion guards may rather be provided where one of the abrasion guards is located along the outermost sidewall 42 of the rectangular channel 14 as shown in FIG. 5 and the other of said abrasion guards 22 is located along the innermost sidewall 46 of the rectangular channel. In such an embodiment, the abrasion guards may be considered to be respectively an outer rectangular channel sidewall abrasion guard and an inner rectangular channel sidewall abrasion guard.

Although abrasion guards 22 such those shown in the embodiments of FIGS. 4 to 6 may be optionally used in various embodiments of the system 10 as described herein, the abrasion guards 22 do not substantially increase the surface area from which forces from a train passing over the rails 20 are exerted on the composite polymer crossties 12; in other words, these rail guards do not substantively increase a load-bearing area of the crossties, as would otherwise be provided by conventional tie plates used in wooden rail assemblies. Therefore, the assembly 10 generally consists of a plateless system, that is one absent a force-distributing plate. Unlike force-distributing plates which are used with conventional wooden crossties and variations thereof in the case of conventional concrete crossties, the optional abrasion guards noted herein are provided for the purposes of inhibiting abrasion damage and fracturing of the composite polymer crossties 12 at certain points of the railseat 18 maintaining rectangular channel 14. The various embodiments of abrasion guards 22 disclosed herein do not act to substantially increase the surface area of the railseat 18 to distribute compressive forces over a larger area of the crosstie.

Additionally, in some embodiments, such as the ones shown for example in FIGS. 5 and 6, the abrasion guard 22 may be fashioned to have a flange portion 48 which extends along a portion of the top surface 16 of the composite polymer crosstie 12 towards the composite polymer crossties outer edge 28. In some embodiments, the outer shim 40 may be coupled to the flange portion 48, whereas in other embodiments, the outer shim 40 may be integrally formed with the flange portion 48. The flange portion 48, in the various abovementioned embodiments, may have a passage made therein (not shown) for receiving therethrough a portion of the fastener 34 employed with outer rail clip 32. By having the flange 48 receive therethrough a portion of the fastener 34, the abrasion guard 22 is resistant to movement and as such is not able to move out of place in the rectangular channel 14. Vibrations caused by repeated train travel over the rails 20 may cause unsecured abrasion guards 22 to move from the desired position and thus in certain applications it may be desirable to protect against abrasion guard 22 movement.

With reference to FIGS. 7 to 9, an alternative rail assembly 100 will now be described in accordance with another embodiment. In this embodiment, the rail assembly 100 again makes use of composite polymer crossties 112 upon and across which one or more rails 126 are mounted and secured via respective rail clips 130, 132. Rather than to provide a rectangular rail receiving channel, as shown above with reference to FIGS. 1 to 6, a wedge-shaped cutout 114 is fashioned in a top surface 116 of the crosstie 112 so to receive inclined a correspondingly shaped railseat 118 therein. To secure against lateral travel of the railseat 118 once in position, the rail clips 130, 132, in accordance with one example, are preassembled with the crossties 112 via respective screw-type fasteners 135 to substantially define thereon the rail load bearing surface therebetween. For instance, respective clip anchoring structures 134 may be anchored to the crosstie via respective anchoring fasteners (e.g. screw type threaded fasteners or the like) so to define the rail load bearing surface therebetween, for instance between respective shoulders 136 thereof. In this example, a collar 138 is further disposed about respective anchoring structures 134 so to further define the rail load bearing surface, namely in providing for a direct lateral contact with the rail once so disposed therebetween. Accordingly, the collar 138 may act to provide a similar function as that provided by the inner and outer channel sidewall abrasion guard portions described above with reference to the embodiments of FIGS. 4 to 6. Otherwise, the anchoring structure shoulders 136 may be disposed to abut directly or substantially directly against the railseat 118 to directly limit a lateral travel thereof once installed therebetween.

In either configuration, a rail-engagement portion 140 may be slidingly engaged (in this embodiment) with the anchoring portion 134 in a pre-assembled configuration and ready for deployment upon rail installation (i.e. see FIG. 8).

With particular reference to FIG. 9, once the crossties 112 have been laid and the rails 126 disposed thereon between respective clips 130, 132, the rail engagement portions 138 and 140 may be laterally slid into position such that a rail-engaging toe 142 (and toe cap) thereof operatively slides onto the railseat 118 to secure it into position upon the crosstie rail load-bearing surface defined between the clips 130, 132.

The person of ordinary skill in the art will appreciate that different rail clips may be used in the present context without departing from the general scope and nature of the present disclosure, namely so as to couple the railseat to a crosstie in the appropriate position between the rail clips.

Having now generally described the rail assembly in accordance with different illustrative embodiments, the composite polymer crossties used therefor may be fabricated, in some embodiments, according the compositions and methods disclosed in United States Patent Application Publication number US 2006/0226247 A1, published Oct. 12, 2006 to Abramson, et al. and entitled “Railway Ties and Structural Elements” and U.S. Pat. No. 8,252,216, issued Aug. 28, 2012 to Abramson, et al. and entitled “Method for the Production of Railway Ties”; the entire contents of each one of which are hereby incorporated herein by reference. Other compositions and methods wherein a composite polymer crosstie beyond those disclosed in the abovementioned documents may also be suitable and accordingly the instant disclosure should not be limited thereto. Accordingly, the composite polymer crosstie may be fabricated, in some embodiments, from a composition comprising at least an asphaltic component, a polymeric composition component and a strengthening agent. Furthermore, in some embodiments, the strengthening agent may be fibres which are pre-included in the input polymeric component. Additionally, the fibres may be included, in some embodiments, in the starting mix pre-included in the polymeric component. The fibres may, in some embodiments, be glass fibres.

Exemplary Crosstie Compositions and Fabrication Methods

By way of example only, the composite polymer crossties comprise an asphalt component, a polymeric composition component and a strengthening agent component pre-included in the polymeric component (thus forming a fiber-reinforced plastics component) and optionally plastics chosen from the group consisting of virgin plastics, recycled plastics, and combinations and mixtures thereof. Also, as noted above, in some embodiments, the composite polymeric crossties comprise an asphalt component, a polymeric composition component and a strengthening agent component which is not pre-included in the polymeric component. In some embodiments, the asphalt component comprises between 15% and 95%, by weight of the composite polymer crossties and the total polymeric component content comprises between 5 and 85% by weight of the crosstie. It should be noted that although a minor amount of impurities may be present in the starting materials, such as moisture, the effect on the manufacturing process of the composite structural element is negligible.

In preferred embodiments, the asphalt component comprises about 65% to 85% by weight of the total weight of a given composite polymer crosstie. More preferably, the asphalt component, in some embodiments comprises about 70% to 80% by weight of the total weight of the composite polymer crosstie. Preferably, the total polymeric component comprises about 10% to 45% by weight of the total weight of the composite polymer crosstie. More preferably, in some embodiments, the total polymeric component comprises about 15% to 40% by weight of the total weight of the composite polymer crossties. Even more preferably, the total polymeric component comprises about 20% to 30% by weight of the total weight of the composite polymer crossties.

The fiber-reinforced plastics component, in some embodiments comprises between about 25% and 75% by weight of the total polymeric component content. In some embodiments, the fiber-reinforced plastics preferably comprises between about 30% and 70% by weight of the total polymeric component content. However, in most preferred embodiments, the fiber-reinforced plastics component comprises between about 40% and 60% by weight of the total plastics component content. In some embodiments, the composite polymer crossties are formed from about 75% of an asphalt component, about 11% of a glass fiber-reinforced polypropylene component and about 14% of a high-density polyethylene component.

While the composite polymer crossties are typically formed from an asphalt component, fiber-reinforced plastics and other plastics, the composite polymer crossties of the instant disclosure may further comprise an elastomer in a proportion of about 0 to 80% by weight. Preferably, the elastomer comprises between 0 and 30% by weight of the composite polymer crosstie.

Typically, asphalt used in the composite polymer crosstie of the instant disclosure is recycled asphalt that has been crushed and subsequently screened for size. For example, the asphalt component is typically passed through a series of screens having progressively smaller square openings. Larger asphalt particles are caught in the first screens while finer particles are caught by later screens. In some embodiments, for example, greater than about 75% of the asphalt is able to pass through a screen having 0.75 inch square openings. However, in preferred embodiments, at least 50% of the asphalt is able to pass through a screen having 0.5-inch square openings. For example, suitable fines of asphalt material for use have a size from ¾″ to about ¼″, which are readily available from asphalt manufacturers.

Polymeric materials suitable for use in composite polymer crossties of the instantly disclosed system may be chosen from, for example, low-density polyethylene (LDPE), high-density polyethylene (HDPE), and polypropylene (PP). Additionally, although virgin polymeric materials or, in other words, virgin plastics materials, may be used to form the composite polymer crossties, in some embodiments it may be preferable to use recycled plastics materials so as to reduce the amount of waste in our environment. Such recycled plastics materials may be polymeric materials such as, for example, polyvinyl chloride (PVC), low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), and combinations and mixtures thereof.

The polymeric material component, in some embodiments, is prepared for incorporation into the composite polymer crosstie during the manufacturing process of the composite polymer crossties, by aligning the mesh sizing with that noted above for the asphalt component or smaller. The polymeric component may also be sized as required by pelletizing, grinding or flaking or otherwise provided at a suitable particle size.

The polymeric component, when provided as a fibre-reinforced plastics component, may be, for example glass-filled polypropylene with a pre-determined proportion of glass fibres. Such a material is readily available commercially and as a recycled material where the glass is intertwined with the polypropylene and is continuous throughout the polypropylene component. Embodiments utilizing glass-filled polypropylene are preferred as the inclusion of the glass fibres enhances the strength of the composite polymer crosstie. Other fibers (such as carbon fibers or silicon fibers) may also be utilized in various embodiments to reinforce the polymeric component and thus the composite polymeric crossties.

In addition to the asphalt component, the fiber-reinforced polymeric components and other plastics materials, the composite polymer crossties in some embodiments may further comprise an elastomer. The elastomer is preferably tire rubber that has been recycled from sources such as scrap tires. In such embodiments, at least about 75% of the elastomer is able to pass through a screen mesh having 0.25-inch square openings. However in preferred embodiments, at least about 75% of the elastomer is able to pass through a screen mesh having 0.125-inch square openings.

Furthermore, in some embodiments, the composite polymer crossties may be made from more than one composition. For example, a first portion and a second portion. The first portion and the second portion comprise the asphalt component, the polymer component and the strengthening agent as described above. However, the first portion may comprise from about 15% to 75% asphaltic component and from about 85% to 25% of a first polymeric component, and optionally a strengthening agent. in some embodiments, the first polymeric component comprises about 50% of a plastics material and about 50% of a glass fibre-filled recyclable thermoplastic material, such as a glass fibre-filled polypropylene, acting as the strengthening agent. In such embodiments, the second portion may comprise from about 20% to about 85% by weight of an asphaltic component and from about 15% to about 80% by weight of a second polymeric component, and optionally a strengthening agent. In some embodiments, the second polymeric component comprises a glass fibre-filled recyclable thermoplastic material as a strengthening agent

Briefly, composite polymer crossties may be manufactured utilizing the first and second portions noted above according to the method as disclosed in U.S. Pat. No. 8,252,216. For example, the first and second portions may be separately prepared and blended. The first and second portions are then separately heated to a temperature suitable to at least melt a portion the polymeric component and then processed in processors operable to heat and feed said blends separately as composite asphalt plastic compositions to pump means associated with a co-extrusion die. The heated and pliable first portion is then pumped into a first section of a mold to form a core portion of the composite polymer crosstie, and the heated and pliable second portion is simultaneously pumped into an outer portion of the mold to form the outer portion of the composite polymer crosstie. However, in some embodiments, it may be preferable to reverse the order such that the second portion is used to form the core and the first portion is used to form the outer portion.

TESTING EXAMPLES

Composite polymer crossties produced from compositions as noted above were tested to determine if composite polymer crossties for use in the instantly disclosed system met the specifications laid out in Section 5.3.3., Chapter 30, Part 5 of AREMA (American Railway Engineering and Maintenance-of-Way Association) manual (2012) regarding Engineered Composite Ties. Briefly, a composite polymer crosstie suitable for use in railway systems must meet the mechanical and performance requirements set forth in Table 30-5-1 of the abovementioned section AREMA manual. The laboratory testing was therefore performed in accordance with the specific elements set forth in Chapter 30, Part 2, and entitled “Evaluative Tests for Tie Systems”.

The subject composite polymer crossties each weighting approximately 350 lbs., having dimensions of about 102 inches in length and cross-sectional dimensions of about 7 inches by 9 inches were tested. The rails were coupled to the composite polymer crossties using generic 1:20 cant intervening tie plates with a contact surface area substantially matching of the railseat anchored to the crosstie surface using screw-spikes and Pandrol™-type E2055 rail clips were used to couple the rails to the generic tie plates. It should be noted that such tie plates used to couple the rails to the crossties are not considered to “force-distributing” as they do not substantially increase the surface where downward force from the rail is applied to the crosstie. Such tie plates coupled to the crossties are used as intervening anchoring points for the clips. Holes for receiving therein the screw-spikes were pre-drilled where the fastener location was countersunk to accommodate the unthreaded portion of the screw-spike and the remainder of the hole was drilled at a smaller diameter for fixture of the threaded portion of the screw-spike to the crosstie. The smaller diameter portion of the hole was drilled through and exposed on the opposing side of the crosstie.

Rail/Plate Area Compression Test

This test was performed to determine the ability of the crossties to resist railseat loads. Briefly, the test consists of applying a vertical load on a pre-determined area. There are two methods which were used in testing the composite polymer crossties of the instant disclosure. In any and all cases, the maximum elastic deformation while under load should not exceed ¼-inch, with permanent deformation after release of the compressive force not exceeding ⅛-inch within 1 minute of releasing the load. The first method uses the rail itself (i.e. devoid a force-distributing plate) having a surface area contacting the composition polymer crosstie of 5½ inches by 9 inches. The second method uses a force-distributing plate having a surface area contacting the rail of 7¾ inches by 14 inches. A pressure, according to the test parameters, was applied at 900 psi (44,550 lbs.) for the rail only first method and 921 psi (100,000 lbs.) for the force-distributing plate second method.

The results of the Rail/Plate Compression Test are as follows:

TABLE 1 Pressure Max. Deflection Applied Deflection (psi) Sample Tie (psi) (inch) (1 min. @ 0 psi) #1 - Method 1 900 0.165 0.003 (Rail Compression) #2 - Method 2 921 0.193 0.005 (Plate Compression)

According to the AREMA testing parameters, the pass/fail requirements are set at 0.250 inch for max deflection and 0.125 inch for residual deflection. As clearly shown in Table 1 above, the composite polymer crossties and system disclosed herein passed the test. Additionally, in the long term, there was no evidence of permanent deflection. The tester also noted that upon removal of the compression device, the top surface of the composite polymer crossties were in pristine condition and this was achieved without the aid of any protective pad or interim force-distributing plate of any kind.

Embedded Screw/Spike/Pull-Out Test

This test was performed to determine the ability of the crossties to resist withdrawal of the rail fastening system (spikes). In conducting this test a 6½-inch long spike is inserted 4½-inches into the composite polymer crosstie. A pull-out load was applied at 1 inch per minute and a minimum extraction load of 5,000 lbsf (pound force) is required to pass the test.

The results of the Embedded Screw/Spike/Pull-out Test are as follows:

TABLE 2 Extraction Load Sample Tie (lbsf) #1 15,890 #2 17,300

As noted above the pass/fail requirement for this test is a minimum extraction pull-out load of 5,000 lbsf. As show in Table 2, both sample composite polymer crossties passed the Embedded Screw/Spike/Threaded Insert Pull-out test and generated values of at least three times the required minimum.

Spike Lateral Restraint Test

The Spike Lateral Restraint Test was performed to determine the ability of a screw-spike to resist lateral movement. Briefly, the spike is driven in the tie to a normal working depth and a load is applied laterally to 0.2-inch at a rate of 0.2-inch per minute. A load/deflection curve is then generated and a maximum load is recorded. It should be noted, that there is no pass/fail criteria provided for AREMA for this test.

The results of the Spike Lateral Restraint Test are as follows:

TABLE 3 Load @ 0.2 inch Sample Tie displacement #1 3715 #2 3891

Tie and Fastener System Wear-Deterioration Test

The Tie and Fastener System Wear-Deterioration Test was performed to determine railseat deterioration and fastener system performance in heavy axle load environments due to repeated load. In this test a complete track system is emulated where two rails are coupled to the composite polymer crosstie and the crosstie is solidly fixed to the test bed. This testing was preformed using standardly shaped polymer crossties of the compositional embodiments discussed above devoid of the rectangular channel noted above in one set of tests (noted below as example Tie and Fastener System Wear-Deterioration Test 1) and in another set of tests using polymer crossties of the compositional embodiments discussed above having the rectangular channel milled in the top surface for receiving the railseat therein (noted below as example Tie and Fastener System Wear-Deterioration Test 2).

Briefly, the testing machine comprises a load frame with a servo-controlled dual action hydraulic actuator. The test load is distributed through to load arm set at an angle of 27.5 degrees from vertical. The load is transmitted equally to each of the two railheads of a full crosstie using the appropriate fastening system. A load of 65,000 lbsf was cyclically applied to the set-up, for a lateral top vertical ratio of 0.52. An abrasive environment must also be simulated on each rail seat for this test. Accordingly, water drip nozzles were positioned over the field and gauge sides of each railseat. Clean and dry sand was also spread on both sides of the railseat.

To measure static and dynamic lateral head displacement during the test, a displacement meter was placed behind the railhead and railbase on each railseat. Deflections were monitored at regular intervals (500,000 cycles minimum) and tracked throughout the test to ensure that there was no excessive movement.

After completing the pre-test procedures, a head measurement under static load was taken to establish a benchmark. After completing the static load measurement, the wear/abrasion test was initiated and under normal conditions is for either 3,000,000 cycles, or until failure, at a frequency of 2.8 Hz. Any abnormalities were noted. Upon completion of the wear/deterioration test, the rail seat assemblies were examined and photographed. The static load test was then repeated. The dismantled components were then examined for sign of failure/damage and the rail seat deterioration maximum depths, if present, were measured.

In order to pass the test, no deflection during the test should exceed 0.2000 inches and none of the actual components under test (in this case the composite polymer crosstie) should fail.

Tie and Fastener System Wear-Deterioration Test 1

The results of the Tie and Fastener System Wear-Deterioration Test 1 are as follows. In this set of testing, standardly shaped polymer crossties (i.e. devoid of a rectangular channel milled in the top surface for receiving therein the railseat of a railway rail) were used (not shown in the figures). The rails were coupled to the polymer crosstie using commonly known intervening tie plates which were coupled to polymer crosstie by four screw spikes each. Briefly, the rail rests on the tie plate and a pair of tie clips interact with the railseat and the tie plate so as to couple the rail to the polymer crossties in a manner commonly known in the art for coupling railway rails to wooden crossties. The test, as noted above, was to be run for at least 3,000,000 cycles with close monitoring of the components for signs of breakage (failure) of a given component and/or head lateral displacement of the railhead in excess of 0.200 inch, which would represent a fail.

During the test two notable events occurred. Firstly, at 1,423,000 cycles one of the tie plates broke (Tie Plate B) at the shoulder and therefore allowed for rotation of the rail. Since the composite polymer crosstie being tested did not fail, the broken tie plate was changed and the testing resumed. Secondly, at 2,675,00 cycles the tie plate in the same position as the previous broken tie plate failed and again, allowed for rotation of the rail. This second broken tie plate was changed and the testing continued. These breakage points, and leading up to the failure, can be clearly seen in the lateral head displacement data present in Table 4, below.

At the completion of the testing, the components were assessed and the following observations were made.

Tie Plates—Tie plate A showed no signs of fatigue fissuring and was used throughout the test. As noted above, tie plate at position B required two changes and the cause of the failure was unknown.

Rail Clips—All four rail clips performed well and no signs of permanent deformation where observed.

Screw-spikes—No damage or signs of failure were noted with the screw-spikes. Even the spikes that were re-driven with respect to the tie plate changes at position B performed well.

Composite Polymer Crossties—The composite polymer crosstie was examined for signs of wear and deterioration. It is interesting and surprising to note that, unlike wooden crossties, the surface of the composite polymer crosstie showed virtually no signs of abrasion after the fatigue test. The section under the tie plate which was not directly under the rail was noted by the tester to be “pristine”, thus edges of the tie plates did not dig into the top surface of the composite polymer crossties whatsoever. Reference lines drawn on the composite polymer crosstie to center the tie plates were still visible after the testing. No pitting or abrasion marks were measured at any location on the tie. Therefore the composite polymer crossties as disclosed herein have wear characteristics equal to or better than concrete crossties, which are significantly more expensive to manufacture. In order to obtain such wear characteristics with concrete crossties, a cushion mat is required which was not used in the testing of the instant composite polymer crossties.

The composite polymer material from which the crossties were fabricated created a thread pattern for the spikes which was extremely effective at holding said spikes even when “re-spiked” to change the broken tie plate, noted above. Unlike in the maintenance of conventional wooden (and in some instance concrete) crossties no filler or epoxy was used in the re-driving of the screw-spikes and the system did not show any signs of a reduction in the retention properties of the screw-spikes in the composite polymer crosstie—thus showing a significant improvement over the characteristics of conventional wooden crossties. This surprising property of the composite polymer crossties disclosed herein is shown with respect the to the lateral head displacement values noted below in Table 4.

TABLE 4 Number of Seat A Seat A Seat B Seat B Cycles Railhead Railbase Railhead Railbase Static Before 0.067 0.017 0.077 0.006 8,000 0.046 0.011 0.046 0.004 50,000 0.046 0.011 0.049 0.006 300,000 0.046 0.009 0.045 0.004 500,000 0.047 0.008 0.045 0.003 800,000 0.049 0.009 0.044 0.003 1,100,000 0.048 0.009 0.058 0.007 1,423,000^a 0.052 0.009 0.074 0.003 1,425,000^b 0.049 0.009 0.049 0.004 1,700,000 0.049 0.008 0.048 0.006 2,100,000 0.049 0.008 0.048 0.005 2,500,000 0.049 0.008 0.68 0.010 2,675,000^c 0.050 0.008 0.075 0.008 2,765,000^d 0.052 0.007 0.040 0.008 2,929,000 0.049 0.008 0.043 0.007 Static After 0.055 0.013 0.058 0.013 ^aBefore, but close to the above-noted first tie plate failure ^bAfter the above-noted first tie plate failure ^cBefore, but close to the above-noted second tie plate failure ^dAfter the above-noted second tie plate failure

As shown in Table 4, the lateral head displacement values for the Static Railhead displacement either maintained initial values or actually decreased with usage (Static deflection for Seat A Railhead before=0.067 initial reading vs. Static deflection for Seat A Railhead after=0.055; Static deflection for Seat B Railhead before=0.077 vs. Static deflection for Seat B Railhead after=0.058), unlike with wooden or other conventionally used crossties. Therefore, the spikes, when used in the instantly disclosed composite polymer crossties either maintain a consistently low deflection value or in fact tighten, as opposed to loosening as is seen and problematic in conventional crossties, by virtue their composition.

With respect to the above testing of the composite polymer crossties used in the instantly disclosed system, it was surprisingly discovered that the holding properties of the crossties for the screw-spikes were noted to be exceptional as compared to conventional wooden crossties. The holding properties of a given crosstie are correlated through the lateral head displacement measurements. For example, with the use of conventional wooden crossties one would expect both higher initial lateral head displacement values and a higher increase in deflection values as the crosstie progressed through the test, which as observed by the data of Table 4, is clearly not the case with use of the instantly disclosed system. The lateral head displacement values of the instantly disclosed system remained substantially constant throughout the testing. Furthermore, as no cushion mats or surface-area-increasing force-distributing plates were used in the testing, it was shown that the instantly disclosed system does not require the use of cushion mats that may erode to surpass the wear properties od wooden crossties. Also, the abrasion normally suffered by conventionally used wooden crossties was not observed. As noted above, following the test, no abrasion of the composite polymer crossties was seen in the area contacted by the tie plate/rail.

Additionally, surprisingly, with reference to Table 4, even when the Tie Plate B suffered catastrophic failure at 1,423,000 and 2,675,000 cycles, respectively, only a marginal increase in the lateral head displacement values were observed. This indicates that the instantly disclosed system may be capable of continuing to function for a significant number of cycles (or train passes) even with a broken tie plate. Therefore, an improved safety aspect may be provided by the instantly disclosed system.

Tie and Fastener System Wear-Deterioration Test 2

The results of the Tie and Fastener System Wear-Deterioration Test 2 are as follows. In this set of testing, polymer crossties having a rectangular channel milled into the top surface for receiving therein the railseat of a railway rail were used as is shown, for example in FIGS. 1a to 1c and the assembly as shown in FIGS. 2a to 3b. No abrasion guards in the rectangular channel where employed in this testing. The test, as noted above was to be run for at least 3,000,000 cycles with close monitoring of the components for signs of breakage (failure) of any components and/or head lateral displacement of the railhead in excess of 0.200 inch.

At 2,841,634 cycles it was noted that in a side of the rectangular channel outward (Seat A Railbase) in the direction of force from a load arm (i.e. the field-side of the railseat and rectangular channel), that the railseat had become embedded in the polymer tie material and the test was stopped.

Following the completion of the testing, it was noted that all four of the rail clips performed well and showed no sign of permanent deformation aside from expected abrasion marks at expected points. Additionally, the screw spikes showed no signs if unusual wear or abrasion, however the spike located nearest the point where the railseat had become embedded in the polymer tie material was noted to have less resistance when removed compared to other spikes. The polymer crossties were observed to be overall structurally sound. No cracking or permanent bending was apparent at any point on the polymer crossties.

Surprisingly, contrary to that commonly seen in wooden crossties, the rectangular channel, created by the milling in the top surface, did not show any signs of abrasion. Therefore, using the polymer crossties with a rectangular channel and system as described herein may maintain toe load by the rail clip compared to conventional wooden crossties and also such a system appears to be resistant to a gap being formed between the bottom of the railway rail and the crosstie as is a known problem with wooden crossties. Additionally, in the instantly disclosed system, no cushion mats are located between the railseat and the crosstie as are used with concrete crossties. These cushion mats are known to flatten and deteriorate where, similar to wooden crossties, a gap begins to forms between the bottom of the railway rail and the crosstie as the cushion mats deteriorate.

With exception of the spike located nearest the point where the railseat had become embedded in the polymer tie materials, the remaining screw spikes retained their high torque values and the system performed very evenly, without losing any retention properties of the screw spikes. The instantly disclosed system, compared to conventional wooden crossties, was extremely efficient in holding and maintaining the screw spikes through out the test.

The results of the nominal head and base displacements as a function of the number of cycles for Tie and Fastener System Wear-Deterioration Test 2 are shown below in Table 5.

TABLE 5 Number of Seat A Seat A Seat B Seat B Cycles Railhead Railbase Railhead Railbase Static Before 0.095 0.007 0.098 0.018 500 0.052 0.002 0.054 0.005 282,000 0.052 0.003 0.048 0.001 644,000 0.052 0.004 0.049 0.005 950,000 0.052 0.004 0.049 0.005 1,250,000 0.056 0.005 0.050 0.005 1,550,000 0.058 0.005 0.050 0.005 1,850,000 0.068 0.006 0.051 0.005 2,082,000 0.070 0.006 0.051 0.005 2,149,000 0.072 0.005 0.052 0.005 2,456,000 0.078 0.006 0.053 0.005 2,674,000 0.081 0.007 0.051 0.005 2,748,000 0.081 0.007 0.050 0.005 2,841,634 N/A*(>0.063) 0.008 0.050 0.004 Static After N/A N/A N/A N/A *No value is available because the transducer had reached its physical limit (extension) when acquiring a max value.

Therefore, using the instantly disclosed system wherein no tie plates or cushion mats are utilized and the polymer crossties have a rectangular channel for receiving therein the railseat of a railway rail, consistent head displacement values in the 0.050 inch range were observed (Seat B Railhead of Table 5). The values returned for Seat A Railhead beginning around 1,550,000 cycles can be attributed to test design and the railseat embedding in the side of the rectangular channel outward in the direction of force from a load arm as discussed above. Accordingly, in some embodiments, an abrasion guard may be applied in the rectangular channel, as discussed in more detail above to prevent the railseat from embedding in the side walls and thus protect the rectangular channel.

Compared to conventional wooden crosstie rail coupling systems and the system tested in Tie and Fastener System Wear-Deterioration Test 1, the system of Tie and Fastener System Wear-Deterioration Test 2 utilizes only 2 screw spikes per coupling of the railseat to the polymer crosstie, as opposed to 4. Additionally, as noted above, no tie plates or cushion mats were utilized in Tie and Fastener System Wear-Deterioration Test 2. Surprisingly, using the system described in Tie and Fastener System Wear-Deterioration Test 2 and shown in the figures, the results showed that the polymer crossties of the instant disclosure and the system of Tie and Fastener System Wear-Deterioration Test 2 were comparable to the Tie and Fastener System Wear-Deterioration Test 1.

It is to be understood that the above description it is intended to be illustrative, and not restrictive. Many other embodiments will be apparent to those skilled in the art, upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Although the present invention has been described with reference to specific exemplary embodiments, it will be evident that various modifications and changes may be made to these embodiments without departing from the broader spirit and scope of the disclosed subject matter as defined by the appended claims.

Claims

1. A railway tie assembly for securing a rail along a railway track, the assembly comprising:

a plurality of composite polymer crossties fabricated from a composition comprising an asphaltic component, a polymeric composition component and a strengthening agent; and

a pair of rail clips for securing the rail across each of said composite polymer crossties, wherein each of said rail clips comprises a rail-engagement portion configured to engage a corresponding railseat, and an anchoring portion to be anchored to a given crosstie and cooperate with said rail-engagement portion, once installed, to secure said corresponding railseat against a load-bearing surface of said given crosstie.

2. The assembly as defined in claim 1, wherein an anchoring of the rail to said crossties is maintained or strengthened under use by virtue of said composition.

3. The assembly as defined in claim 2, wherein said load-bearing surface is defined by a correspondingly dimensioned channel formed within said given crosstie so as to at least partially receive said corresponding railseat therein.

4. The assembly as defined in claim 3, wherein said anchoring portion comprises a fastener-receiving aperture formed therein to receive cooperative engagement of a fastener therethrough such that, upon fastening said fastener to said given crosstie through said aperture, an anchoring pressure is applied through said rail-engagement portion to said corresponding rail seat.

5. The assembly as defined in claim 4, wherein said fastener is a screw-type threaded fastener.

6. The assembly as defined in claim 3, wherein said load-bearing surface is defined by a corresponding pair of correspondingly dimensioned channels formed within said given crosstie so as to at least partially receive said corresponding railseat therein.

7. The assembly as defined in claim 6, wherein said channels are outwardly inclined channels formed within said given crosstie so as to at least partially receive inclined said corresponding railseat therein.

8. The assembly as defined in claim 7, wherein an outward inclination is from about 1:40 cant to about 1:10 cant.

9. The assembly as defined in claim 7, wherein an outward incline of said at least one channel is about 1:20 cant.

10. The assembly as defined in claim 6, wherein each of said rail clips further comprises a respective inner shim and outer shim to be disposed so as to downwardly bias said rail-engagement portion against said corresponding railseat as said fastener is secured to said given crosstie.

11. The assembly as defined in claim 10, wherein said outer shim has a greater thickness than said inner shim.

12. The assembly as defined in claim 6, further comprising respective lateral abrasion guards to be located along an outermost sidewall region of each of said respective channels.

13. The assembly as defined in claim 10, further comprising respective lateral abrasion guards to be located along an outermost sidewall region of each of said respective channels, wherein said abrasion guards further comprise a flange portion extending from said respective channels and to which is coupled said outer shim.

14. The assembly as defined in claim 6, further comprising respective base abrasion guards to be located within said respective channels along a base thereof to have said corresponding railseat rest thereon.

15. The assembly as defined in claim 6, further comprising respective inner abrasion guards to be located along an innermost sidewall region of each of said respective channels.

16. The assembly as defined in claim 1, wherein said load-bearing surface is defined by a corresponding pair of outwardly inclined wedges formed within said given crosstie so as to at least partially receive inclined said corresponding railseat therein.

17. The assembly as defined in claim 1, wherein each said anchoring portion is mounted in pairs to said given composite crosstie such that facing structural features thereof define said load-bearing surface therebetween while at least partially directly or indirectly limiting a lateral travel of said rail once received thereon.

18. The assembly as defined in claim 17, further comprising a respective collar to be fitted about said facing structural features to further limit said lateral travel.

19. The assembly as defined in claim 17, wherein said rail-engagement portion is slidingly engaged in a pre-assembled configuration with said anchoring portion to slide laterally against said corresponding railseat into a rail-engagement configuration.

20. The assembly as defined in claim 1, wherein said composition comprises from about 15% to about 95% by weight of said asphaltic component, from about 5% to about 85% by weight of said polymeric composition component wherein said polymeric composition component includes said strengthen agent.

21. The assembly as defined in claim 1, wherein said composition comprises a first portion comprising from about 15% to about 75% by weight of a first asphaltic component and from about 25% to about 85% by weight of a first polymeric composition component and a second portion comprising from about 20% to about 85% by weight of a second asphaltic component and from about 15% to about 85% by weight of a second polymeric composition component; wherein each of said first portion and said second portion includes said strengthening agent and wherein during manufacturing of said composite polymer crosstie said first portion and said second portion are suitably heated and co-extruded wherein one of said first portion or said second portion forms a core portion of said composite polymer crosstie and the other forms an outer portion of said composite polymer crosstie.

22. The assembly as defined in of claim 20, wherein said strengthening agent includes fibres or reinforcing agents.

23. The assembly as defined in claim 21, wherein said strengthening agent includes fibres or reinforcing agents

24. The assembly as defined in claim 22, wherein said fibres are glass fibres.

25. The assembly as defined in claim 23, wherein said fibres are glass fibres.

26. The assembly as defined in claim 1, wherein said asphalt component comprises asphalt particles such that at least 75% of the asphalt particles can pass through a 0.75″ mesh screen.

27. The assembly as defined in claim 1, wherein said asphalt component comprises asphalt particles such that at least 50% of the asphalt particles can pass through a 0.5″ mesh screen.

28. The system as defined in claim 1, wherein said composition is adapted to allow said railseat to rest directly on said load-bearing surface without adversely increasing wear of said crossties under use.

29. The system as defined in claim 1, wherein said composition is adapted to allow said railseat to rest directly or indirectly on said load-bearing surface absent a surface area-increasing force-distributing plate without adversely increasing wear of said crossties under use.

30. A railway track comprising:

a plurality of composite polymer crossties fabricated from a composition comprising an asphaltic component, a polymeric composition component and a strengthening agent, wherein said crossties are disposed at regular intervals along the railway track;

one or more rails each composed of rail segments juxtaposed end-to-end along the railway track, a respective railseat thereof disposed crosswise upon a respective load-bearing surface of each of said crossties; and

respective pairs of rail clips securing respective ones of said rail segments to each of said composite polymer crossties, wherein each of said rail clips comprises a rail-engagement portion engaging a corresponding railseat, and an anchoring portion anchored to a given composite crosstie and cooperating with said rail-engagement portion to secure said corresponding railseat against said respective load-bearing surface of said given crosstie.

31. The railway track according to claim 30, wherein an anchoring of said rail segments to said crossties strengthens under use by virtue of said composition.

32. The railway track according to claim 30, wherein said rail segments are disposed directly upon said load-bearing surface in absence of a corresponding tie plate, wherein said composition allows said absence without adversely increasing wear of said crossties under use.

33. The railway track according to claim 30, wherein said rail segments are disposed upon said load-bearing surface via respective abrasion guards, only, in absence of a corresponding tie plate, wherein said composition allows for said absence without adversely increasing wear of said crossties under use.