Repetitive or cyclic rail loading deteriorates the engineering properties of the railway ballast by particle crushing and rearrangement. Most of the classical elasto-plastic models are unable to predict such ballast degradation despite successfully predicting the overall load–deformation behavior during cyclic densification. In this context, the present …
Dahal and Mishra [18] simulated ballast particle breakage by calibrating the crushing criteria in the DEM simulation by particle crushing laboratory test. Polyhedral ballast shapes were compared with spherical shaped ballast stones. Commonly the literature states that shape and breakage are essentials when simulating track ballast …
sented allowing a visualization of the evolution of crushing. 2 Selection of railtrack ballast Rail track ballast should be crushed rock, nickel slag or crushed gravel composed by strong and durable particles having sizes typically between 0.25 in (6.4mm) and 2.5 in (64mm). In order to select a specific track ballast, economic
As such, a ballast that undergoes crushing under impact will likely sustain the required asperities for particle interlock, even if the ballast particles are of smaller sizes, while abraded ballast particles will not. Evaluation of …
The ballast bed of railway has excellent advantages, such as low construction cost and ease of maintenance and repair, and has been widely used in many countries across the world. However, under the action of long-term train load, the ballast bed could suffer natural deterioration such as ballast wear and crushing.
The research on ballast bed has a long history, including ballast crushing [1] [2], ballast bed settlement, ballast aggregate distribution, the force between the sleeper and track bed, ballast ...
It is necessary to study the crushing characteristic to improve the travelling comfort of trains. In this study, limestone blocks composing the railway ballast with size …
In the ballasted tracks, a fouled ballast layer will be formed due to the interpenetration of ballast and fine particles (from subgrade filler and ballast crushing and abrasion), that is, a mixed interlayer [[11], [12]] of ballast and fine particles.
Experimental study and theoretical analysis on ballast particle crushing based on energy dissipation and release. Qihang Hu, Rui Gao, Jing Chen, Zhiwen Yuan. Article 119664 View PDF. Article preview.
Ballast is a crucial material used in the construction of railways, roads, and other infrastructure in Kenya. Ballast crushing machines are used to crush stones into small pieces to make ballast ...
at the interface between the clean and polluted ballast is strictly dependent on the dielectric contrast between these materials. As an example, Fig. 5 shows a GPR survey conducted over a railway track in a section with a sharp variation of the ballast conditions. In more detail, the ballast is clean in the range
Ballast Crushing. We also carry out the mining of sand and ballast for building and construction purposes . Ballast is mined from our rich bedrock seated on vast acres of stone land located in Mombasa. We have the …
Deiros et al. [4] analyzed the influence of ballast crushing caused by tamping on track performance by using discrete element method. Feng B [5] used COSMOSMotion software and ANSYS to analyze the tamping mechanism. Liu C [6] used PFC3D software to establish the numerical simulation model of the large-scale …
DOI: 10.1016/JPGEO.2017.03.007 Corpus ID: 125386306; Discrete element modeling of the single-particle crushing test for ballast stones @article{Wang2017DiscreteEM, title={Discrete element modeling of the single-particle crushing test for ballast stones}, author={Bo Wang and Ullrich Martin and Sebastian …
A ballast crushing probability distribution model was established, which incorporated the Weibull model. The anticipation of ballast crushing probabilities can be achieved …
The ballast layer transmits loads from railway sleepers to the subgrade [3]. Owing to the continuous traffic loads and track maintenance activities, the ballast particles degrade during the service life of railway tracks [4], [5]. The crushing of ballast particles is governed by their fracture strength, mineralogy, shape, and size [6], [7].
Crushing. The crushing of ballast grains is responsible for the degradation of ballast and modeling should take it into account. Implementation of the crushing phenomenon is simply done via splitting the polyhedral particles into smaller polyhedrons whenever they fulfill a certain failure criterion. Since the particle is assumed ideally rigid ...
of the laboratory single ballast particle crushing tests on a typical ballast, denoted here as ballast A, which is a grano-diorite comprising mainly plagioclase (30%), quartz (25%) and alkali feldspar (20%). Thirty tests were conducted on each agglomerate type, as this is considered to give a statistical representation of
Ballast crushing refers to the process of breaking down large rocks and stones into smaller pieces that are used as ballast in various construction projects. Ballast is typically a mixture of gravel, crushed stone, and other materials that provide stability to structures such as railroad tracks, roadways, and foundations. ...
Experimental studies on ballast breakage of single particle and uniform aggregate, considering both shape and size effect.. The mass loss of flaky particles and elongated particles can be 10 times the mass loss of cube particles.. There is a critical size whose particle breakage needs the highest energy per volume.. The progress of …
This paper aims to reveal the crushing process of ballast particles more accurately from the perspective of energy. In this study, a series of single-particle uniaxial compression tests (SPUCT) were conducted using a high-speed camera system. The multi-stage crushing behavior and crushing characteristics of the particles have then been ...
Criteria for evaluating crushed stone ballast cleaning technologies are given: performance of a ballast cleaning machine - estimated by operating speed, volume of cut out and cleaned ballast (per ...
Wang et al. [20] presented a discrete element model to simulate the single grain crushing test for irregularly shaped ballast particles. The single grain crushing tests were performed on ballast ...
A ballast crushing probability distribution model was established, which incorporated the Weibull model. The anticipation of ballast crushing probabilities can be …
Forest roads, Road construction, Ballast, Rock crushing, Road rehabilitation, Road surface, Mobile rock crushers. 1 This report distinguishes between ballast material and the fine-graded aggregate specified as a surface course for main roads. Surfacing aggregate is usually produced in a two-stage crushing process, and is a different
DeAtley Crushing Service, Inc. provides rock-crushing services throughout the Western United States by utilizing seven mobile rock-crushing plants. Atlas Sand & Rock, Inc. provides North Central Idaho and Southeastern Washington with pre-mix concrete and aggregates. ... And lastly, Mainline Rock & Ballast, Inc. provides the railroad industry ...
The modeling process of a BPM for a single ballast stone in this paper can be taken as a reference for DEM simulation of ballast aggregation, which can be used to …
The results showed that the ballast particles were more likely to crush in the early stages of the LAA process due to the sharp corners and edges of the larger …
The deformation of ballast under cyclic rail loading consists of three mechanisms, ballast crushing, friction sliding and volumetric compaction [31, 47]. …
In this study, the splitting behavior of ballast grain with varying particle sizes under diametrical compression was examined to investigate the size effect and the Weibull characteristics of ballast …
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