Wave Amplitude Attenuation and Wear Prevention Methods for Non-Wood-Timber Railroad Ties

Abstract

Non-wood-timber (NWT) railroad ties such as concrete remove cushion and pressure wave attenuation provided by wood timber railroad ties. I provide methods to reintroduce cushion and wave attenuation by means of adding an elastomeric sole. To further increase wave attenuation a layer of ground automobile tire is placed between the hardpan and ballast. Also, reclaimed asphalt is an inexpensive means to create hardpan that reduces railroad tie pumping.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]Not ApplicableSTATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT[0002]Not Applicable. The invention has no sponsor.REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX[0003]Not ApplicableBACKGROUND OF THE INVENTION[0004]Definitions for this patent application are:[0005]the word sole refers to the material that isolates the railroad tie from ballast.[0006]a non-wooden-timber railroad tie shall be denoted “NWT tie.”[0007]aramid fibers such as poly-para-phenylene terephthalamide may be referred to by the trade name Kevlar a trademark of DuPont or Twaron a trademark of Teijin.[0008]Railroads the world over traditionally utilize wooden timber ties 1 placed in a rock ballast 2,4 as seen in FIGS. 2 and 3. The ties 1 maintain the gauge or distance between the steel rails 3. Steel spikes and plates, not shown, affix rails 3 to wood ties 1. Ties 1 are placed atop a ballast base 2 that forms the le...

AI Technical Summary

Benefits of technology

[0024]FIG. 22 through 36 inverted trapezoidal profiles, with the small face down and large face up, create the “wedge” railroad tie 18,20. The wedge maintains the tamped ballast 4 locked in place and ballast 2,4 grips the tie's elastomeric wrap around sole material 19,20 to reduce wave amplitudes and frequencies, as well as maintain three dimensional congruency.

Problems solved by technology

Wood tie 1 costs increase with feed stock scarcity.

Attempts to increase wood tie 1 longevity such as U.S. Pat. No. 4,609,144 “Railroad tie cover,” have not proven effective.

NWT 6 ties have been successful for passenger rail and light tonnage rail cars, but have not proven as durable in heavy tonnage railways which comprise a large percentage of the North American rail industry.

Furthermore, concrete ties like the trapezoid tie 7 are prone to erosion on the bottom and sliding transversely and longitudinally since the ballast 2,4 cannot grip concrete.

The burden fatigues rails and increases failure rates.

Pumping also places further undue fatigue on rails 3 which further exacerbates failure rates.

Concrete tie 7 life expectancy of 10 years is much shorter than wood ties 1 life of 30 to 50 years, which creates more frequent maintenance intervals and cost.

The plastic rectangular tie 11 life expectancy is much shorter than wood ties 1, which creates more frequent maintenance intervals and cost.

Cost and logistics of hot bituminous substance are the primary problems with hot asphalt products.

NWT tie pumping severity is worse than wood timber ties due to the aforementioned tie bottom erosion as the ballast acts as a grinder to pulverize the weakly bonded material of the NWT tie.

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