1. 研究目的与意义（文献综述）

Rail corrugation is a wave type wear of therail surface with a wide variety of wavelengths. Corrugation shows as an undulation of the rail surfacewith typical wavelengths between 25 and 80mm. Rail corrugation is one of themost serious and expensive problems experienced by transit systems, railcorrugation is a frequently occurring rail wear pattern that arises mostly incurves, the corrugation phenomena is considered forvehicles with low axle load, running at low speed in curves with small radius.

Rail corrugation is caused everywhere due tothe combination of various factors, rail corrugation could be caused by someresonances as:

1. The torsionalvibration of the wheel-set in curve.

2. Excessively largecreepage between wheel and rail, which could be caused by insufficiency ofrolling radius difference between high-rail side wheels or caused by large ofattack between rail and wheel.

3. Oscillation of wheelload, which could be caused by vertical vibration including contact stiffnessor rail rolling vibration.

4. Stick-slip betweenthe rail and wheel when accompanying with the oscillation of the wheel load, itwas found that the stick-slip is caused mainly by the vibration of wheel load.

   The aim of the project is to analyze the finiteelement of twin disc rig test and find out effective solutions to reduce or getrid of the corrugation problem on rail.

   Theobjectives of analyzing the twin disc rig test are:

1. To simulate the corrugation as closely aspossible in relation to torsional vibration.

2. To measure the corrugation wavelength due tothe torsional vibration.

3. To measure the resonance of the corrugationfrequency on the lower disk.

4. To investigate the effect of wheel torsionalvibration.

5. To conform the assumptions that made in thetheories.

6. To increase the safety, reduce noise andlife cycle costs, also to optimize the maintenance costs

1-Domestic ResearchStatus:

With the accelerating process and thecontinuous expansion of urban population and the growing size of motor vehiclesmake the city transportation problems worse. Therefore, it is urgent to find aneffective and environmentally friendly transportation method to solve theproblem.

In 1879, the first steam traction subwayline was built in London and England, which created a precedent for subwayconstruction. Today, Britain, Germany, the United States, Japan and othercountries have all established a complete urban rail transit network due toeconomic strength and technology.

Dueto the level of restrictions, the construction of rail transit in Chinese urbanareas started relatively late. Before 2000, only three cities Beijing,Shanghai, and Guangzhou had rail transit lines. Since the beginning of the 21stcentury, with the rapid development of Chinese economy and urbanization, Withthe acceleration of the process, Chinese urban rail transit has entered aperiod of great development.

In the next decade, China will build 15 to 20subways each year, and a total of 7,395 kilometers of subway lines will bebuilt, with a total value of 380 billion yuan.

Currently, Changsha, Wuhan, Qingdao andChengdu are carrying out the construction of a rail transit network. It isestimated that by 2020, the total length of urban rail transit in China willexceed 3,000 kilometers, and China will have 33 cities with 177 subway lines[1].

LiuXueyi[2] has classified the resonance of thecorrugation as a dynamic type (induced by vibration) and non-dynamic type(metallurgy, material, stress, deformation, etc). and he has classified theforce type resonance into self-excited vibration and feedback vibration.

The dynamic type is generally believed thatthe wave length is determined by the vibration characteristics. It is a mixtureof a limited number of wavelengths, which is related to one or more vibrationmodes in the wheel-rail system.

Hecomprehensively considered taht the rail corrugation caused by verticalvibration of the wheel-rail system, bending vibration of the wheel pair andtorsional vibration of the wheelset.

Wang Bukang[3, 4]studied the mechanism of short and longcorrugation resonance, and he found that the vertical contact force and thecreep force can affect the corrugation problem.

LiuQuyue [5, 6] Used JD1 track and rail friction simulationtester to investigate the rail corrugation in laboratory experiments, inaddition, they also combined with the problems of the rail corrugation of(Shanghaia-Hangzhou) line, and analyzed the materials of the wave-abrasiverail. Due to the plastic deformation the results showed that the railcorrugation is caused by the contact vibration of the wheel-rail system, thewheel-rail tangential force is an important factor in the formation anddevelopment of corrugation.

Inthe recent years Liu and Meehan did researches and investigations on squealnoise under friction characteristics in2016 [7]and in 2015 they simulated the effect ofrolling speed and angle of attack in[8], also in 2014 Liu and Meehan did aninvestigation of the effect of relative humidity on lateral force in rollingcontact and curve squeal[9] and in 2013 they investigated the effect oflateral adhesion and rolling speed on wheel squeal noise[9]

2-Overseas ResearchStatus:

Since 1930 the German railways suffered fromcorrugation, the year 1950 marks the start of a series of new review ofcorrugation studies done in [10]. And in 1970 the studies continued with newtest sites in[11, 12].

In Britain 1970 the corrugation was serve onhigh-speed lines, the survey showed some surprising anomalies in [13, 14].

In Canada 1986a new mass transit system wasdesigned to keep the system free from corrugations and its consequences[15].

Suda et al. began the theoreticaland experimental study on rail corrugation in 1986 and presented itinternationally in 1988 in[16]. Continuing the study, acorrugation simulator was developed[17].

From 1993, Matsumoto and his colleagues started the study on corrugationon sharp curve in order to prevent the corrugation generated mainly onlinear-motor-driven subway. Matsumoto, Suda, Ishida and Sumi joined in theresearch project in The JSA, and carried out full-scale stand tests, modelstand tests, train running tests, field researches and numerical simulationsand successfully investigated the formation mechanism and countermeasures ofcorrugation produced on low rail of sharp curved track[18].

In 1998, JR East started the research project of formation mechanism ofcorrugation generated on low rail of sharp curve of commuter lines. Trainrunning tests on commercial commuter lines were carried out in this project[19].

The existence of a pinned–pinned-mode type corrugation is confirmed byan investigation of Hiensch et al[20], in 2017 Aglat and Arthurdesigned a test rig for railway curve squealing noise, we can adjust and modifythe design inorder to be appropriate for our experiment[21].

Table 1 A list of available test rigsfor wheel rail studies

No.	Name of the testing setup	Owner	Location
1	Full-scale Roller Rig [22]	Southwest Jiaotong University (SWJTU)	Chengdu,China
2	Full-scale Roller Stand[23]	National Traffic Safety amp; Envir. Lab. (NTSEL)	Tokyo,Japan
3	Full-scale Rail Wheel Test Rig[24]	Voestalpine Schienen (VAS)	Leoben,Austria
4	BU300 Roller Rig[25]	Lucchini C.R.S	Lovere,Italy
5	Naples Vehicle Roller Rig[26]	Ansaldo Transport Research Centre	Naples,Italy
7	Reduced-scale Rolling Rig[27]	TNO-TPD	Delft,Netherlands
8	Wheel/Rail Tribological Rolling Rig[28]	Southwest Jiaotong University	Chengdu,China
10	Twin-Disk Rig[29]	University of Huddersfield (formerly MMU)	Huddersfield,UK
11	Two-Disc Test Rig[30]	University of Queensland	Sydney,Australia
12	Scaled-BogieTest Bench[31]	Université Catholique de Louvain	Louvain, Belgium
13	SUROSTwin-Disk Test Machine[32]	Sheffield University Rolling Sliding	Sheffield,UK
14	ISVRWheel–Rail Test Rig[33]	Institute of Sound amp; Vibration Research	Southampton,UK
15	BCRRESpinning Rail Test Rig[34]	University of Birmingham	Birmingham, UK
16	INRETSBogie Test Rig[26, 35]	French Transport Research Institute (INRETS)	Grenoble, France
17	ScaledWheelset Roller Stand[36]	NationalTraffic Safety amp; Environ. Lab. (NTSEL)	Tokyo,Japan
18	OerlikonTest Machine[37]	DelftUniversity of Technology	Delft,Netherlands
19	Scaledwheel on rail track-wheel Test Rig[38]	CranfieldUniversity	Cranfield,UK
20	Twin–DiscRolling–Sliding Machine[39]	RailwayTechnical Research Institute	Tokyo,Japan
21	Twin–DiscMachine[40]	East Japan Railway Company (JR East)	Saitama, Japan
22	ScaledRoller Test Rig[41]	MDM Lab	Pistoia, Italy
24	Rollingcontact two disc test rig[42]	Wuhan University of Technology	Wuhan,China

2. 研究的基本内容与方案

themain objective of this experiment is to obtain and understand the reasonsbehind the rail corrugation in order to find solutions that can reduce thecorrugation on rail. also, we can take a consideration of the previous researchand experiment that have been done by other researchers and continuing whatthey couldn’t approach in their research. also, we will compare our numericaltheory result with the experimental results, find a solution or a mechanism ofreducing the rail corrugation.

in order to measure and carry out ourexperiment purposes of the rail corrugation, we need to design and build ageneral downscale roller test bench model, to design the roller test bench we willbe using cad software like (solidworks) and then analyze the finite element ofthe twin disc using ansys software.

this rolling test bench design not only canbe used to measure and investigate the frequency of rail corrugationwavelength, but also can be used to investigate more than one target liketorsional vibration, squeal noise and the contact and friction between thewheel and rail etc.

3. 研究计划与安排

(1^st-2^nd)week: collectthe relevant technical reference and materials according to the selected topic,and complete the thesis proposal, reference translation, and literature search.

(3^rd) week: confirm and classify the appropriate partsof the test bench.

(4^th-6^th) week: confirm the assembling, installing andmodeling of the test bench, and using cad (solidworks)to design and draft thetest bench parts.

4. 参考文献（12篇以上）

[1] 曾青中 and 韩增盛, "城市轨道交通车辆,"ed: 成都: 西南交通大学出版社, 2009.

[2] 刘学毅, "钢轨波形磨耗成因研究," 博士学位论文. 成都: 西南交通大学, 1996.

[3] 王步康, 董光能, 刘永红, and 谢友柏, "钢轨短波长波浪形磨损的安定性分析," 2004.