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Wei, Z. (author), Nunez, Alfredo (author), Boogaard, M.A. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)
In this paper, we present a method for evaluating the performance of railway crossing rails after long-term service. The method includes 1) 3D profile and hardness measurements; 2) finite element simulation of wheel/rail interaction; and 3) numerical prediction of rail degradation. We conducted a case study on a crossing that had been in service...
journal article 2018
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Naeimi, M. (author), Li, S. (author), Li, Z. (author), Wu, J. (author), Petrov, R.H. (author), Sietsma, J. (author), Dollevoet, R.P.B.J. (author)
This research presents a coupled thermomechanical modelling procedure for the wheel-rail contact problem and computes the flash-temperature and stress-strain responses when thermal effects are present. A three-dimensional elasto-plastic finite element model was built considering the wheel-track interaction. When the wheel is running on rail,...
journal article 2018
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Jamshidi, A. (author), Hajizadeh, S. (author), Su, Z. (author), Naeimi, M. (author), Nunez, Alfredo (author), Dollevoet, R.P.B.J. (author), De Schutter, B.H.K. (author), Li, Z. (author)
In this paper, a decision support approach is proposed for condition-based maintenance of rails relying on expert-based systems. The methodology takes into account both the actual conditions of the rails (using axle box acceleration measurements and rail video images) and the prior knowledge of the railway track. The approach provides an...
journal article 2018
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Wei, Z. (author), Boogaard, M.A. (author), Nunez, Alfredo (author), Li, Z. (author), Dollevoet, R.P.B.J. (author)
This paper describes an approach for characterizing the dynamic behavior of the vehicle/track interaction at railway crossings. In the approach, we integrate in situ axle box acceleration (ABA) measurements with roving-accelerometer hammer tests to evaluate the influence of train speed, train moving direction (facing and trailing directions),...
journal article 2018
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Yang, Z. (author), Boogaard, M.A. (author), Wei, Z. (author), Liu, Jinzhao (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)
This paper presents an analysis of the transient contact solutions of wheel-rail frictional rolling impacts calculated by an explicit finite element model of the wheel-insulated rail joint (IRJ) dynamic interaction. The ability of the model to simulate the dynamic behavior of an IRJ has been validated against a comprehensive field measurement in...
journal article 2018
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Yang, Z. (author), Boogaard, M.A. (author), Chen, Rong (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)
This paper presents an analysis of the transient contact solutions of wheel-rail frictional rolling impacts calculated by an explicit finite element model of the wheel-insulated rail joint (IRJ) dynamic interaction. The ability of the model to simulate the dynamic behavior of an IRJ has been validated against a comprehensive field measurement in...
journal article 2018
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Wei, Z. (author), Nunez, Alfredo (author), Li, Z. (author), Dollevoet, R.P.B.J. (author)
In this paper, we investigate the capability of an axle box acceleration (ABA) system to evaluate the degradation at railway crossings. For this purpose, information from multiple sensors, namely, ABA signals, 3D rail profiles, Global Positioning System (GPS) and tachometer recordings, was collected from both nominal and degraded crossings....
journal article 2017
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Jamshidi, A. (author), Nunez, Alfredo (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)
This paper presents a condition-based treatment methodology for a type of rail surface defect called squat. The proposed methodology is based on a set of robust and predictive fuzzy key performance indicators. A fuzzy Takagi-Sugeno interval model is used to predict squat evolution for different scenarios over a time horizon. Models including...
journal article 2017
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Deng, X. (author), Qian, Zhiwei (author), Li, Z. (author), Dollevoet, R.P.B.J. (author)
The half-space assumption has been employed in many solution methods for non-conforming contact problems in elasticity such as the Hertz theory and the Kalker's variational theory. It is generally believed that to guarantee acceptable accuracy in these half-space-based methods, the characteristic size (twice length of one semi-axis) of the...
journal article 2017
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Li, S. (author), Li, Z. (author), Nunez, Alfredo (author), Dollevoet, R.P.B.J. (author)
A three-dimensional (3D) finite element (FE) dynamic frictional rolling contact model is presented for the study of short pitch corrugation that considers direct and instantaneous coupling between the contact mechanics and the structural dynamics in a vehicle-track system. In this study, we examine the system responses in terms of vibration...
journal article 2017
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Jamshidi, A. (author), Faghih Roohi, S. (author), Hajizadeh, S. (author), Nunez, Alfredo (author), Babuska, R. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author), De Schutter, B.H.K. (author)
Railway infrastructure monitoring is a vital task to ensure rail transportation safety. A rail failure could result in not only a considerable impact on train delays and maintenance costs, but also on safety of passengers. In this article, the aim is to assess the risk of a rail failure by analyzing a type of rail surface defect called squats...
journal article 2017
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Naeimi, M. (author), Li, Z. (author), Petrov, R.H. (author), Sietsma, J. (author), Dollevoet, R.P.B.J. (author)
A new downscale test rig is developed for investigating the contact between the wheel and rail under impact-like loading conditions. This paper presents the development process of the setup, including review and synthesis of the potential experimental techniques, followed by scalability, mechanical and operational analysis of the new setup. The...
journal article 2017
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Molodova, M. (author), Oregui Echeverria-Berreyarza, M. (author), Nunez, Alfredo (author), Li, Z. (author), Dollevoet, R.P.B.J. (author)
This paper presents a health condition monitoring system for insulated rail joints (IRJs) based on axle box acceleration (ABA) measurements. The ABA signals from all the wheels of the measuring train are processed to extract those characteristics that better represent the quality of the IRJ. Then, different indicators are used for damage...
journal article 2016
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Yang, Z. (author), Li, Z. (author), Dollevoet, R.P.B.J. (author)
By considering real wheel and track geometry and structures, as well as their coupled interaction, an explicit finite element method is applied to simulate the transition of wheel–rail rolling from single-point tread contact to two-point tread-flange contact. The evolutions of the contact position, stress magnitude and direction, adhesion–slip...
journal article 2016
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Burgelman, N. (author), Li, Z. (author), Dollevoet, R. (author)
This paper investigates the effect of the calculation of the longitudinal location of a wheel rail contact point on the wheelset’s motion in a vehicle dynamic simulation. All current vehicle dynamic software programs assume that the contact between wheel and rail takes place in the vertical plane through the wheelset’s rolling axis. However,...
journal article 2016
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Oregui Echeverria-Berreyarza, M. (author), Li, S. (author), Nunez, Alfredo (author), Li, Z. (author), Carroll, R (author), Dollevoet, R.P.B.J. (author)
Rail joints are a weak component in railway tracks because of the large impact and wheel-rail contact forces. Every train passage contributes to the deterioration of rail joints, causing visible (e.g. battered rails) and invisible (e.g. loose bolts) damages. The invisible damage cannot be detected by the commonly performed visual inspection,...
journal article 2016
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Wu, J. (author), Petrov, R.H. (author), Naeimi, M. (author), Li, Z. (author), Dollevoet, R.P.B.J. (author), Sietsma, J. (author)
White etching layer (WEL) is a frequently observed microstructural phenomenon in rail surface, formed during dynamic wheel/rail contact. It is considered as one of the main initiators for rolling contact fatigue cracks. There are several hypotheses for the formation mechanism of WEL. However, due to the complicated wheel/rail contact...
journal article 2016
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Li, Z. (author), Zhao, X. (author), Dollevoet, R.P.B.J. (author)
A methodology for the determination of a critical size of surface defects, above which RCF can initiate, has been developed and demonstrated with its application to the passive type of squats under typical Dutch railway loading conditions. Such a methodology is based on stress evaluation of transient rolling contact at the defects, for which...
journal article 2016
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Burgelman, N.D.M. (author), Li, Z. (author), Dollevoet, R.P.B.J. (author)
When a train runs through a turnout or a sharp curve, high lateral forces occur between the wheels and rails. These lateral forces increase when the couplers between the wagons are loaded in compression, i.e., a rear locomotive pushing a train or a front locomotive braking a train. This study quantifies these effects for a train that begins...
journal article 2016
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Oregui Echeverria-Berreyarza, M. (author), Nunez, Alfredo (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)
This paper presents a sensitivity analysis of railpad parameters on vertical railway track dynamics, incorporating the nonlinear behavior of the fastening (i.e., downward forces compress the railpad whereas upward forces are resisted by the clamps). For this purpose, solid railpads, rail-railpad contact and preloaded springs are defined in a...
journal article 2016
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