Corrugation reduction strategy

Investigation on the development mechanisms of short pitch corrugation

NeTIRail-INFRA Mid-Term Conference 4th November 2016, Brussels

Shaoguang Li, Zili Li, Alfredo Nunez Vicencio, Rolf Dollevoet

MotivationWhat is rail corrugation?

Romania, Bartolomeu – Zarnestinear Brasov

Turkey, Kayas-Lalahannear Ankara

Short pitch rail corrugation: 20-80 mm, on straight tracks or at gentle curves

Disadvantages: giving rising to the system dynamics and vibrations,accelerating the system components degradations

Current solution: rail grinding

• Literature review

• New modelling approach and some field observations

• Some results to explain corrugation initiation

Outline

• Contact solutions during corrugation development

• Summary

• Future work

• Experimental instrumentation

Fieldwork (Suda, 2002, etc.)

Laboratory based test rig (Matsumoto, 2002; Bellette et al., 2011)

• Analytical/numerical simulation (see next page)

Literature review: main approaches

• Analytical/numerical simulation (see next page)

• Metallurgical characterization

WEL or BEL (Feller and Walf, 1991; Li et al., 2016), wear resistance, etc.

• Frequency domain (Grassie et al., 1982; Hempelmann et al., 1991; Wu andThompson , 2002; etc.)

Treatment of the model

Applications and limitations

• Time domain (Igeland 1996, Ilias 1999; Xie and Iwnicki, 2008; etc.)

Literature review: numerical models

• Time domain (Igeland 1996, Ilias 1999; Xie and Iwnicki, 2008; etc.)

Treatment of the model

Applications and limitations of present treatment

Wheel/rail model Hertz/non-Hertz Steady/non-steady Coupling

• FE model

New modelling approach

Some field observations

• Short pitch corrugation appears at certain locations in thesame track;

• Characteristics of the corrugation vary with differentfastening systems;fastening systems;

• Corrugation is found sensitive to the fastening system (Ilias,1999; Cui et al., 2016).

Method

• Parameter variation to study how corrugation initiates

• Contact solutions to understand the development ofcorrugationcorrugation

Some results on corrugation initiation

• Parameter: railpad lateral irregular wear

a) Worn outer borders b) New railpad

Contact solutions during corrugationdevelopment

Smooth

Corrugation trough

Corrugation in FE model

Pressure Shear stress

Summary

• Literature review and the advantage of the modellingapproach.

• Method based on field observations.

• A parameter variation scheme is performed and thecorrugation initiation is observed.

• Contact solutions in the presence of corrugation reveal the• Contact solutions in the presence of corrugation reveal thedevelopment.

Future work

• Further parameters need to be investigated for a betterunderstanding the initiation and the control strategy;

• Experimental tests will be performed to provide a validationand also an easy method to access the healthy state of thetrack system.track system.