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Showing 1 to 10 of 10 for “"Railroad Ballast"”.
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Machine learning techniques for identifying railroad ballast degradation
Railroad ballast is a layer of uniform sized crushed aggregate particles placed between, below and around the crossties. Railroad ballast transfers the load from crossties to the subgrade layer, provides lateral track stability and facilitates the drainage of water. Repeated traffic loading and …
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Investigation of aggregate properties influencing railroad ballast performance
… goes toward the maintenance and renewal of ballast. Railroad ballast is a uniformly-graded coarse aggregate placed between and immediately underneath the crossties. Large variations in the source properties of new ballast aggregate materials provided by suppliers resulted in the need to …
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On the shear strength of polyurethane coated railroad ballast
Unbound nature of railroad ballast aggregates causes abrasion and degrada- tion predicaments due to heavy train axle loads. Polyurethane reinforcement of ballast layer is a candidate solution to these problems. However, not many polyurethane reinforcement applications have been studied until the …
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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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Integrated computational and experimental framework for the assessment of railroad ballast life-cycle behavior
Ballast, typically comprising large sized aggregate particles with uniform gradation, is an essential layer in the railroad track substructure. Functions of ballast include facilitating load distribution and drainage, maintaining track geometry and track stability, and providing track resilience …
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Performance of Geogrid Reinforced Ballast under Dynamic Loading
Railroad ballast consists of open 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 …
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Shared memory parallelization for large scale 3D polyhedral particle simulations
Granular materials such as sands, gravels, railroad ballast, and rock are inherently highly heterogeneous and anisotropic. While they are known as one of the most widely used materials in industry, their complex behaviors remain not fully understood. Particle-based numerical methods were introduced …
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Advanced image analysis and techniques for degradation characterization of aggregates
… sources are known to affect pavement and railroad track mechanistic behavior and performance significantly in terms of strength, modulus and permanent deformation. Under repeated traffic loading aggregate particles used in construction of pavement and railroad track are routinely subjected …
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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
… railcars has influenced 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 …
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Development of ice-bonded ballast in sub-freezing temperatures and its effect on maintenance operations during a winter rail break
… temperatures result in ice formation within the ballast layer of railroad track. Given the proper moisture and fouling conditions, the retained moisture bonds ballast particles together changing the mechanical properties. For above-freezing temperatures, longitudinal track resistance (f0) to …