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Improving the Performance of Rail Fastening System Evaluation

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Improving the Performance of Rail Fastening System Evaluation PAPER Improving the Performance of Rail Fastening System Evaluation Tadashi DESHIMARU,Improving Track the StructurePerfo randm aComponentsnce of R Laboratory,ail Fast Trackenin Structureg Syst Divisionem Ev aluation Shingo TAMAGAWA, Track Structures and Components Laboratory, Track Technology Division Masato NOGUCHI, Track Structures and ComponentsTadashi Laboratory, DESHIMA TrackRU Technology Division Track Structure and Components Laboratory, Track Structure Division Hiroo KATAOKA, Track Structures and Components Laboratory, Track Technology Division Shingo TAMAGAWA Masato NOGUCHI Hiroo KATAOKA RegardingTrack St rJapaneseuctures a ntestd C methodsompone nforts Lrailabo fasteningratory, Tr systems,ack Tech itn owaslogy confirmedDivision that the rail tilting angle obtained in a biaxial loading test did not agree with the angle calculatedRegarding using Japanese a conventional test methods rail tiltingfor rail analysis fastening model. systems, To address it was confirmedthis problem, that a the rail tilting angle obtained in a biaxial loading test did not agree with the， angle calculated us- ing calculationa conventional method rail fortilting biaxia analysisl loading model. using To an address FEM analysisthis problem, model a calculationwhere various method for stiffnessbiaxial loadingproperties using regarding an FEM the analysisrail fastening model, systems where can various be expressed stiffness as properties non-linearity regard， - ing wasthe railproposed fastening and systemsits validity can was be expressedconfirmed. as non-linearitIn addition, y,a wasstudy proposed on the optimiz and itsation validity wasof confirmed. a method forIn addition,testing rail a studyrestraint on thewas optimization carried out ofthrough a method experimental for testing validation rail restraint wasunder carried various out through conditions. experimental validation under various conditions. Key wordsKeywords: rail :fastening rail fastening systems, systems, performance performance verification, verification, FEM analysis, FEM analysis, rail tilting rail angel, tilting rail angle, restraint rail restraint 11.. InIntroductiontroduction DDifferentifferent teststest sare a rconductede conduc tfored thefor purpose the pu ofrp confirmingose of con - ftheirm performanceing the per offor railma nfasteningce of ra systemsil faste nwhiching s yarest eamongms w htheich atrackre a mcomponentsong the t rusedack conom railwayponen ttracks.s used oAmongn railw theseay t rtests,acks . Ainm Japan,ong t hbiaxialese te staticsts, i andn J arepeatedpan, bi aloadingxial st testsatic arean dconducted repeated lforoad theing purposetests ar ofe cverifyingonducted the for performance the purpos eof o fthese veri fsystemsying th e pine rtermsform aofn cfatiguee of th durability.ese syste m s in terms of fatigue durabil- ity. Conventionally, the loading conditions for static and repeatedConv biaxialention aloadinglly, th etests, loa dusinging c oa nsingledition fastenings for sta systemtic and rset,epe areate determinedd biaxial lsooa thatdin gthe t erailsts tilting, usin angleg a s icalculatedngle fast usingening stheyst proposedem set, arailre tiltingdeter analysismined smodelo tha t[1 t-h4]e agreesrail t iwithltin gthe a nrailgle (a) Testing with single fastening system ctiltingalcul aangleted u obtainedsing the in p rtheop otest.sed rHowever,ail tilting it a wasnal yconfirmedsis mode l set [these1-4] atwogre erails w tiltingith th anglese rail dotilt noting agreeangl ein o practice.btained in the test. HoweTherefore,ver, it wa sin c othisnfi rstudy,med t hthees erail tw otilting rail tangleilting c aalculatedngles do nusingot ag rtheee iproposedn practi cfinitee. element method (FEM) model was comparedThere fwithore, ithen t hangleis st uobtaineddy, the rthroughail tilt ina guniaxial angle cloadingalculat - etestd u onsin ag test the track pro ptoo sverifyed fin theite validityelemen oft mthiset hproposedod (FEM analysis) mode l wmodelas co mwhenpar ead low wit stiffnessh the an fasteninggle obta isystemned th rwasoug applied.h a uni a xIina l laddition,oading t ethest ovalidityn a tes oft t therac kbiaxial to ve rloadingify the conditionvalidity o forf t htestingis pro - ptoo sbeed aappliednalysi sto m ao dsingleel wh erailn a fasteninglow stiff nsystemess fas tseten icalculatedng system wusingas a pthepl iproposeded. In a danalysisdition, modelthe va waslidit verifiedy of the bybi acomparingxial loadi nitg cwithond ithetio nresponse for test valuesing to obtainedbe appli ined a t biaxialo a sin loadinggle rail testifastngen oning say teststem track. set c alculated using the proposed analysis model (b) Testing on a test track was verified by comparing it with the response values ob- Fig. 1 Test apparatus for biaxial loading t2.ai nRailed in tilting a biax iangleal load anding t loadingesting on condition a test trac k . Fig. 1 Test apparatus for biaxial loading testing testing There are two methods of static and repeated loading tests tconductedrack. using a track. 2conducted. Rail ti ltinin gJapan ang lfore a nverifyingd loadi nfasteningg condi tisystemon fatigue SStatictatic loadingloadin gtests te sarets aconductedre condu toct eexamined to ex aresponsesmine re - durability; one is conducted using a single fastening system set ssuchpon seass surailch adisplacements rail displac eandmen trail an d cliprail cstress.lip str es s. Rail Ra il and Tthhee otherre ar eis tconductedwo meth ousingds of as testtati trackc and as r eshownpeate din lFig.oad i1.ng ddisplacementisplacemen tduring durin gstatic sta tloadingic loadi ntestsg te isst sverified is veri fagainstied ag atheins t tWhenests c oan fasteningducted i nsystem Japa nof f other v sameerify itypeng f aiss tlaideni ncontinuouslyg system fa - trailhe lateralrail la displacementteral displa climiteme nvalue.t lim i t Theval ucombinede. The c railom bclipine d tonigu thee d utrackrab iatlit yregular; one iintervals,s conduc tae dsingle usin gfastening a singl esystem fasten seting rstressail c lisip verifiedstress i sby v echeckingrified by whether checki ntheg w plothet hrepresentinger the plot therep - swasyst eselected.m set a n dWhen the odifferentther is ctypesondu ofct efasteningd using asystems test t rareack rcombinationesenting th eis coinsidembin athetio nacceptance is inside tareahe a ofcc eptheta nGoodmance area o f auseds sh oonw na itrackn Fi gor. 1 when. Wh theen arail fa sprofiletenin gis s ynotst econstantm of th ein s athem e tdiagramhe Goo ddefinedman d ibyag rtheam types defin ofed spring by th esteels type sas o shownf sprin ing sFig.teel s ttrackype ilongitudinals laid conti ndirection,uously o asn tish etrue tra ofck a a jointedt regu lrail,ar i nteststerv areals , a2.s s hown in Fig. 2. a single fastening system set was selected. When different In static loading tests, the distributed force to be ap- types of fastening systems are used on a track or when the plied in tests using a single fastening system set is derived rail profile is not constant in the track longitudinal direc- from the design loads - load‘ A’ and load‘ B’ - based tion, as is true of a jointed rail, tests are conducted using a on beam theory on an elastic foundation. Load‘ A’ cor- QR of RTRI, Vol. 59, No. 3, Aug. 2018 181 In static loading tests, the distributed force to be applied In static loading tests, the distributed force to be applied reinsp otestsndIns using tstatico a r aloadinga singlerely o fasteningctests,curr itheng distributedsystemload, w sethi lisforcee lderivedoa dto‘ beB ’from applied is t thehe 600 in tests using a single fastening system set is derived from the 600 mindesignor etests co m loadsusingmon - a ll ooadsinglead .‘A’ L fastening oandad‘ loadA’ system‘B’exe -r tbaseds seta fiso onr derivedc ebeam on t htheoryfrome tr athe conk 600 Elastic limit line design loads - load ‘A’ and load ‘B’ - based on beam theory on Elastic limit line wdesignhanic helastic b loadsroa dfoundation.e -n lsoad th e‘A’ tr and ac k Load loadgau ‘B’g‘A’e w- basedhcorrespondsile l oonad beam‘ B to’ theory naa rrarelyro wons Elastic limit line ) Yield line an elastic foundation. Load ‘A’ corresponds to a rarely 2 the track gauge. Following the estimation of distributed ) 400 Yield line anoccurring elastic load,foundation. while load Load‘B’ is the‘A’ more corresponds common load.to a rarelyLoad 2 ) 400 Yield line fooccurringrces, the load, rail whiletiltin loadg an ‘B’gle is i sthe d emorerive dcommon using tload.he r a ilLoad tilt- 2 400 Goodman occurring‘A’ exerts load, a force while on loadthe track ‘B’ is which the more broadens common the load. track gaugeLoad Goodman ‘A’ exerts a force on the track which broadens the track gauge GoodmanLine for 10 5 in‘A’whileg m exertsod eloadl aas force s‘B’ho w narrowsonn ithen F tracki gthe. 3 . which trackThis broadensigauge.s calle d “ theFollowingco tracknven tgaugeio ntheal Line for 105 while load ‘B’ narrows the track gauge. Following the (N/mm 200 cycles 5 (N/mm Line for 10 mwhileestimationethod ”load an dof ‘B’ tdistributedh e narrowsrail til t forces,intheg atrackn thegle railcgauge.al ctiltingula te dangleFollowing by mise derivedan sthe of 200 cycles estimation of distributed forces, the rail tilting angle is derived (N/mm 200 Goodman Line thestimationusingis me thetho drail of i s distributed tiltingcalled model“ p rforces,ac astic showna lthe so lrailu inti o tiltingFig.n.” 3.W angle h Thisen ist h isderivede calledforce Goodman Line cycles using the rail tilting model as shown in Fig. 3. This is called Amplitude stresof Goodmanfor 107 cycles Line
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