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Guo, Y. (author), Liu, Guixian (author), Jing, Guoqing (author), Qu, Jianjun (author), Wang, Shilei (author), Qiang, Weile (author)Ground penetrating radar (GPR) has been applied for ballast layer inspection for two decades, mainly for the analysis of ballast layer fouling levels. However, some issues that affect the inspection quality remain unsolved, such as issues involving the GPR equipment quality (antenna) and the correlation between the GPR indicator and fouling...journal article 2022
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Liu, Guixian (author), Peng, Zhan (author), Jing, Guoqing (author), Wang, Shilei (author), Li, Yaonan (author), Guo, Y. (author)Ground penetrating radar (GPR) is a popular technology for inspecting railway ballast layer, mainly on the ballast fouling level. However, different GPR antennas with different frequencies are suitable for different inspection emphasis and diverse railway lines (weather and sub-structure). In addition, the full-scale track model (with...journal article 2022
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- Guo, Y. (author) doctoral thesis 2021
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Liu, Jida (author), Dong, Changqi (author), An, Shi (author), Guo, Y. (author)Social organizations have become an important component of the emergency management system by virtue of their heterogeneous resource advantages. It is of great significance to explore the interaction between the local government and social organizations and to clarify the key factors affecting the participation of social organizations in natural...journal article 2021
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Zhou, Jia Bin (author), Bai, Yan Qin (author), Guo, Y. (author), Lin, H.X. (author)In general, data contain noises which come from faulty instruments, flawed measurements or faulty communication. Learning with data in the context of classification or regression is inevitably affected by noises in the data. In order to remove or greatly reduce the impact of noises, we introduce the ideas of fuzzy membership functions and the...journal article 2021
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Analysis of Railway Ballasted Track Stiffness and Behavior with a Hybrid Discrete-Continuum ApproachShi, Can (author), Zhao, Chunfa (author), Yang, Yang (author), Guo, Y. (author), Zhang, Xu (author)Railway ballasted track stiffness is an important indicator to identify supporting condition that ensures that the facility is well designed and functioned. Although many studies have been performed on track stiffness based on experimental tests and finite-element methods, the factors influencing the track stiffness have not been completely...journal article 2021
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Guo, Y. (author), Jia, W. (author), Markine, V.L. (author), Jing, Guoqing (author)Ballast rheology is a phenomenon that describes movements of ballast particles due to the discrete nature, which eventually leads to the ballast bed fluid deformation after a long-time service. In most cases, ballast rheology is the main reason of track irregularity that leads to some track defects, e.g., hanging sleeper and mud spots....journal article 2021
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Guo, Y. (author), Markine, V.L. (author), Jing, Guoqing (author)Railway ballast beds bear cyclic loadings from vehicles and deteriorate due to ballast particle degradation (breakage and abrasion), ballast pockets (subgrade defects), fouling (or contamination) and plastic deformation of the beds. Ballast bed deterioration changes the ballast track geometry, which leads to uncomfortable rides, exacerbates...review 2021
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Guo, Y. (author), Zong, Lu (author), Markine, V.L. (author), Wang, Xinyu (author), Jing, Guoqing (author)Lateral and longitudinal resistance of ballasted track are two main indicators for the track stability quantification. Aiming at improving the lateral and longitudinal resistance, nailed sleeper is studied with single sleeper push tests (SSPTs) and discrete element modelling (DEM). The SSPTs were applied to study how much resistance the...journal article 2021
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Jing, Guoqing (author), Jia, W. (author), Wang, Xinyu (author), Markine, V.L. (author), Nålsund, Roar (author), Guo, Y. (author)To enhance the stability of continuous welded rail (CWR) tracks, frictional sleepers have been developed. The frictional sleepers are new types of sleepers with grooves on the bottom, and different bottom grooves improve lateral resistances at different magnitudes. In this study, single sleeper push test (SSPT) and its model with discrete...journal article 2021
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Guo, Y. (author)Electron tomography is a powerful tool in materials science to characterize nanostructures in three dimensions (3D). In scanning transmission electron microscopy (STEM), the sample under study is exposed to a focused electron beam and tilted to obtain twodimensional (2D) projections at different angles; many imaging modes are available such as...doctoral thesis 2020
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Guo, Y. (author), Tian, X. (author), Fang, Guohua (author), Xu, Yue Ping (author)Inter-basin water transfers (IBWT) are implemented to re-allocate unevenly distributed water resources. However, many conflicting objectives associated with society, economy, and environment have made the water resources allocation problem in IBWT more complicated than ever before. Thus, there is a continuous need for in-depth research with...journal article 2020
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Shi, Can (author), Zhao, Chunfa (author), Zhang, Xu (author), Guo, Y. (author)This paper presents a multi-layer railway ballast track and substructure model, where a coupled discrete and continuous method is used for macro-meso dynamic behaviour analysis under moving wheel loads. In this coupled model, the discrete element method (DEM) is utilised to build the superstructure of the ballast track (i.e. rail, fastener,...journal article 2020
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Guo, Y. (author), Zhao, Chunfa (author), Markine, V.L. (author), Jing, Guoqing (author), Zhai, Wanming (author)The discrete element method (DEM) has been confirmed as an effective numerical method for modelling railway ballast, and successfully used to analyse a wide range of ballast-related applications (e.g. geomaterials). However, there still exists some aspects under development. Among them, the model calibration can be the most significant one ...review 2020
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Shi, Can (author), Zhao, Chunfa (author), Yang, Yang (author), Guo, Y. (author), Zhang, Xu (author), Feng, Yang (author)To probe into the mechanical behaviour of railway transition zone from the macro-meso aspects, a numerical model of transition zone is built that hybrids the Discrete Element Method (DEM) and Finite Difference Method (FDM). The DEM is utilised to simulate the ballast bed and sleeper, because it can consider the realistic ballast shapes and...journal article 2020
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Guo, Y. (author), Ji, Yameng (author), Zhou, Qiang (author), Markine, V.L. (author), Jing, Guoqing (author)The rubber-protected ballast (RPB) is made from natural ballast particles and crumb rubber particles. The crumb rubber is shredded waste tires. RPB was chosen to replace the ballast as it has higher resistance to breakage and abrasion. However, the static and dynamic performance of the RPB has not been confirmed yet. Towards this end,...journal article 2020
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Guo, Y. (author), Wang, Jianxi (author), Markine, V.L. (author), Jing, Guoqing (author)With the train speed and axle load increasing, excessive stresses are produced and transmitted to the ballast layer, inducing rapid ballast degradation. To solve this issue, the under sleeper pads (USPs) have been widely applied between sleepers and ballast particles as the elastic layer. In this research, laboratory tests using half-sleeper...journal article 2020
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Guo, Y. (author), Fu, Hao (author), Qian, Yu (author), Markine, V.L. (author), Jing, Guoqing (author)The lateral stability of ballasted track becomes more important because of the safety requirement under the demand of higher train speed and heavier axle load. To increase the lateral resistance of ballast bed, this paper proposes three types of new sleepers, frictional sleepers. The frictional sleepers are sleepers with different shapes of...journal article 2020
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Guo, Y. (author), Markine, V.L. (author), Zhang, X. (author), Qiang, Weile (author), Jing, Guoquig (author)The performance and deformation of ballast bed are significantly influenced by the particle morphology (size and shape), the rheology (translation and rotation), and the degradation (breakage and abrasion). Regarding the ballast particle morphology, the ballast particle size is generally measured by sieving and described with the Particle Size...review 2019
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Guo, Y. (author), Markine, V.L. (author), Qiang, Weile (author), Zhang, Hui (author), Jing, Guoqing (author)Higher speed, more freight and frequent maintenance increase ballast degradation and reduce the ballast lifespan. To reduce ballast degradation, crumb rubber used as buffering aggregates in ballast bed is relatively unexplored and needs more studies, because using it has the advantage of reusing the waster rubber and absorbing the noises. The...journal article 2019