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Automatic detection of squats in railway infrastructure

Molodova, M. (author), Li, Z. (author), Nunez, Alfredo (author), Dollevoet, R.P.B.J. (author)

This paper presents an automatic method for detecting railway surface defects called “squats” using axle box acceleration (ABA) measurements on trains. The method is based on a series of research results from our group in the field of railway engineering that includes numerical simulations, the design of the ABA prototype, real-life...

journal article 2014

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Maintenance decision indicators for treating squats in railway infrastructures

Jamshidi, A. (author), Nunez, A.A. (author), Li, Z. (author)

conference paper 2015

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Experimental Investigation Into the Condition of Insulated Rail Joints by Impact Excitation

Oregui, M. (author), Molodova, M. (author), Nunez, A. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)

This paper presents a feasibility study to determine if the health condition of Insulated Rail Joints (IRJs) can be assessed by examining their dynamic response to impact excitation. First, a reference dynamic behavior is defined in the frequency domain of 50-1200 Hz based on field hammer test measurements performed on a IRJ baseline (i.e., a...

journal article 2015

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Probabilistic defect-based risk assessment approach for rail failures in railway infrastructure

Jamshidi, A. (author), Faghih Roohi, S. (author), Nunez, Alfredo (author), Babuska, R. (author), De Schutter, B.H.K. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)

This paper develops a defect-based risk analysis methodology for estimating rail failure risk. The methodology relies on an evolution model addressing the severity level of rail surface defect, called squat. The risk of rail failure is assessed by analyzing squat failure probability using a probabilistic analysis of the squat cracks. For this...

conference paper 2016

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Sensitivity analysis of railpad parameters on vertical railway track dynamics

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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Monitoring bolt tightness of rail joints using axle box acceleration measurements

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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Key performance indicators using robust prediction modelling to consider squats in railway infrastructure

Jamshidi, A. (author), Nunez, Alfredo (author), Molodova, M. (author), Li, Z. (author), Dollevoet, R.P.B.J. (author)

conference paper 2016

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Health condition monitoring of insulated joints based on axle box acceleration measurements

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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Educación e investigación en ingeniería ferroviaria: tren de mediciones CTO, una sala de clases sobre rieles

Nunez, Alfredo (author), Hendriks, J.M. (author), Li, Z. (author), Dollevoet, R.P.B.J. (author)

La industria ferroviaria a nivel mundial necesita de una gran cantidad de nuevos<br/>profesionales, capaces de resolver los crecientes desafíos que este modo presenta. Siendo una industria por lo general conservadora, atraer a las y los mejores no es tarea fácil. En este resumen, se discuten algunos desafíos del mundo ferroviario y se presenta...

conference paper 2017

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Influencing factors for condition-based maintenance in railway tracks using knowledge-based approach

Jamshidi, A. (author), Hajizadeh, S. (author), Naeimi, M. (author), Nunez, Alfredo (author), Li, Z. (author)

In this paper, we present a condition-based maintenance decision method using<br/>knowledge-based approach for rail surface defects. A railway track may contain a considerable number of surface defects which influence track maintenance decisions. The proposed method is based on two sets of maintenance decision factors i.e. (1) defect detection...

conference paper 2017

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New insights into the short pitch corrugation development enigma based on 3D-FE dynamic vehicle-track coupled modelling in frictional rolling contact

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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A big data analysis approach for rail failure risk assessment

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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Robust and predictive fuzzy key performance indicators for condition-based treatment of squats in railway infrastructures

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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Evaluating degradation at railway crossings using axle box acceleration measurements

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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Preface

Li, Z. (author), Nunez, Alfredo (author)

contribution to periodical 2018

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Method for evaluating the performance of railway crossing rails after long-term service

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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Rail Condition Monitoring using Axle Box Acceleration Measurements: Defect detection in the Netherlands and Romania

Nunez, Alfredo (author), Hendriks, J.M. (author), Moraal, J. (author), Ramirez Fonseca, I. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)

In this paper we discuss rail condition monitoring based on axle box acceleration (ABA) measurements. We present three case studies. The first one in The Netherlands, the detection of local defects with different severity levels (squat A, squat B and squat C) is analysed. The second case from the Faurei testing ring in Romania, the detection of...

conference paper 2018

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Decision support tool based on multi-source data analysis for the tram wheel-rail interface

Xie, Wei (author), Nunez, Alfredo (author), Maas, Ron (author), Li, Z. (author)

This paper presents a methodology to support decision making based on the tram wheel-rail interface condition. The methodology relies on the following measurements: tram failure log-files regarding wheel-sliding events, monitored acoustics data and open source weather information. The proposed methodology consists of three stages: 1) data...

conference paper 2018

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A condition-based maintenance methodology for rails in regional railway networks using evolutionary multiobjective optimization: Case study line Braşov to Zărneşti in Romania

Nunez, Alfredo (author), Jamshidi, A. (author), Wang, H. (author), Hendriks, J.M. (author), Ramirez Fonseca, I. (author), Moraal, J. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)

In this paper, we propose a methodology based on signal processing and evolutionary multiobjective optimization to facilitate the maintenance decision making of infra-managers in regional railways. Using a train in operation (with passengers onboard), we capture the condition of the rails using Axle Box Acceleration measurements. Then, using...

conference paper 2018

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A decision support approach for condition-based maintenance of rails based on big data analysis

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