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Showing 1 to 18 of 18 for “"Track structure"”.
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Development of a track structure condition index (TSCI)
… own and operate nearly 25000 miles of railroad track. Although traffic is generally low volume and low speed, this track serves a vital transportation niche. A technological gap existed, however, in that a simple method was not available for routine condition assessment which is necessary for an …
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Mechanistic analysis of concrete crosstie and fastening system using field-validated finite element model
… and explore possible improvement for current track design standard. The damage of fastening system is one of the most prevalent failure causes for concrete crosstie track, however the current AREMA design standard only includes evaluative tests for the fastening system, rather than a …
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Performance of Geogrid Reinforced Ballast under Dynamic Loading
… graded crushed stone used as a bed for railroad track to provide stability. It plays a significant role in providing support for the track base and distributing the load to the weaker subgrade below. Ballast also helps with drainage, which is an important factor for any type of transportation …
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Automating the Generation of Geometric Information Models to Support Digital Twinning of Existing Rail Infrastructure
… of the digital twinning process for rail infrastructure. Currently, this onerous procedure outweighs the anticipated benefits of the resulting model and expends 74% of the modellers’ effort on converting point cloud data to a model. This is particularly true for rail infrastructure because …
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Interaction cross sections needed for simulation of secondary electron emission spectra from thin metal foils after fast proton impact
… have been implemented into the Monte Carlo track structure code PARTRAC where simulations of secondary electron emission spectra from copper foil have been performed.
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Under ballast mats for railway infrastructure–a North American approach to component characterization
… look for ways to extend the life of their track infrastructure and its components given poor track performance can lead to reduced transportation efficiencies. As such, under ballast mat (UBM) applications have seen growth in the North American (N.A.) freight railroad transportation market. …
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Class III / short line system inventory to determine 286,000 lb (129,844 kg) railcar operational status in Kansas and determination of ballast fouling using ground penetrating radar
… Class III / short line railroad operation and track maintenance costs. Class III railroads earn less than $38.1 million in in annual revenue and generally operate first and last leg shipping for their customers. In Kansas, Class III railroads operate approximately 40 percent of the roughly …
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Characterization of the loading environment for shared-use railway superstructure in North America
… is placing an increasing demand on railway infrastructure. Some of the most critical areas of the infrastructure in need of further research are track components used in high speed passenger, heavy haul, and shared infrastructure applications. In North America, many design guidelines for these …
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Discrete element modeling of railroad ballast using imaging based aggregate morphology characterization
Ballast is an essential layer of the railroad track structure, and provides primarily drainage and load distribution. In general, ballast aggregates are considered as uniformly graded, angular shaped with crushed faces. However, various ballast aggregate gradations and particle shapes are in use …
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Mitigation of differential movements at railroad bridge transition zones
Railroad transitions are track locations that experience a rapid change in track structure, such as a bridge or crossing. These locations are prone to differential movement and require frequent resurfacing to maintain an acceptable track geometry for both passing freight and high-speed passenger …
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Flexural distress and degradation mechanisms in pretensioned concrete beams and railroad crossties
… are an essential component of ballasted railroad track and concrete is a commonly used material for crossties in demanding locations such as heavy axle load (HAL) freight railroads, high-speed rail lines, and rail transit systems. Concrete crossties are often designed as prestressed concrete …
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Railroad decision support tools for track maintenance
… and maintenance scheduling for the entire track structure. Planning track maintenance in this way allows for the effects of changing maintenance timing to be seen explicitly through the disruption risk while considering equipment and other constraints. Managers can then combine the output …
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Development of the track structural capacity rating (TSCR) and example use case for low volume railroad track
Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2026-12-01
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Reproducción, mediante ensayos a escala real, del efecto en la vía de la circulación ferroviaria a alta velocidad
… the effects of those circulation speeds on the track itself is then of great importance not only in order to assist in the proper design of the multilayered track structure, but additionally to analyse the long term behaviour of the track materials. The present research document describes the …
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“Acid-spike” effect in spurs/tracks of the low/high linear energy transfer radiolysis of water : potential implications for radiobiology and nuclear industry
Hydronium ions (H3O+) are formed within spurs or tracks of the low or high linear energy transfer (LET) radiolysis of pure, deaerated water at early times. The in situ radiolytic formation of H3O+ renders the spur and track regions temporarily more acid than the surrounding medium. Although …
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Comparison of the Effects of Cobalt-60 [gamma]-Rays and Tritium [beta][superscript -]Particles on Water Radiolysis and Aqueous Solutions and Radiolysis of the Ceric-Cerous Sulfate Dosimeter at Elevated Temperature
… mainly driven by the chemical action of “short tracks” of high local LET. This same trend in yields of radical and molecular products was also found under acidic conditions as well as in the aerated Fricke dosimeter. One of our main findings was that the measured Fricke yield G(Fe[superscript …
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Radiation biophysical modeling of the FLASH effect: from mechanistic understanding towards clinical endpoint prediction
… (ii) organic radical recombination, (iii) inter-track effects, or (iv) the immune system-driven effect. However, some of these have been discredited by further experiments. Based on these mechanisms, several mathematical models have been proposed. However, most of these have been based on a …