Gradient Elastic Design thiab Log -Rail Impact Optimization of Rail Pads
Dab tsi yog cov qauv tseem ceeb thiab cov yam ntxwv ntawm cov elasticity ntawm gradient elastic tsim nyob rau hauv -rail pads?
Cov qauv tseem ceeb ntawm gradient elastic tsim ntawm hauv qab -rail pads yog apeb- txheej txheem roj hmab sib xyaw, uas yog hnav- txheej tiv thaiv, txheej tsis thiab txheej txhawb nqa los ntawm sab saum toj mus rau hauv qab. Txhua txheej yog ua los ntawm cov ntaub ntawv roj hmab nrog cov elastic moduli sib txawv kom ua tiav gradient elastic faib. Cov hnav- txheej tiv thaiv yog nyob rau hauv kev sib cuag nrog rau hauv qab ntawm txoj kev tsheb ciav hlau, ua los ntawm nitrile roj hmab nrog siab elastic modulus (8-}10MPa) thiab Shore hardness 60-65HA, uas muaj zoo hnav tsis kam thiab shear tsis kam thiab tuaj yeem tiv taus kev sib txhuam thiab cuam tshuam ntawm lub log thiab kev tsheb nqaj hlau. Cov txheej tsis yog txheej hauv nruab nrab, ua los ntawm styrene-butadiene roj hmab nrog nruab nrab elastic modulus (3-5MPa) thiab Shore hardness 45-50HA, uas yog cov txheej txheem tseem ceeb rau kev nqus lub log- rail cuam tshuam thiab tuaj yeem hloov feem ntau ntawm kev cuam tshuam lub zog rau hauv elastic deformation thiab maj mam tso tawm nws. Cov txheej txheem txhawb nqa yog nyob rau hauv kev sib cuag nrog rau saum npoo ntawm tus neeg pw tsaug zog, ua los ntawm cov roj hmab ntuj uas tsis tshua muaj elastic modulus (1-2MPa) thiab Shore hardness 30-35HA, uas muaj kev ua haujlwm zoo elastic rov qab, tuaj yeem cuam tshuam qhov seem seem thiab xyuas kom haum zoo ntawm lub ncoo thiab pw tsaug zog. Cov txheej txheem peb-txheej yog sib xyaw ua ke los ntawm qhov kub thiab txias vulcanization, nrog cov interlayer bonding zog Ntau tshaj los yog sib npaug rau 1.5MPa thiab tsis muaj kev pheej hmoo ntawm delamination thiab poob tawm. Lub elastic modulus txo qis ib qib zuj zus los ntawm txheej txheej sab saud mus rau txheej txheej, paub txog cov kauj ruam-los-kauj ruam buffering ntawm lub log-rail kev cuam tshuam, thiab qhov cuam tshuam kev nqus tau nce ntau dua 60% piv nrog cov tsoos ib txwm elastic ncoo.
Dab tsi yog qhov sib txawv ntawm kev ua tau zoo ntawm gradient elastic nyob rau hauv -rail pads thiab ib txwm ib txwm elastic nyob rau hauv -rail pads?
Qhov sib txawv ntawm qhov kev ua tau zoo ntawm cov gradient elastic nyob rau hauv -rail pads thiab cov tsoos ib leeg elastic nyob rau hauv -rail pads feem ntau yog tshwm sim nyob rau hauv peb yam: cuam tshuam kev nqus efficiency, kev nyuaj siab kis tau tus mob attenuation thiab dynamic deformation. Qhov cuam tshuam kev nqus ntawm cov ntaub qhwv elastic tuaj yeem ncav cuag ntau dua 85%, uas tuaj yeem nqus tau lub log zoo -rail cuam tshuam lub zog tsim tawm thaum lub tsheb ciav hlau hla, thaum qhov cuam tshuam kev nqus ntawm cov tsoos ib txwm elastic pads tsuas yog 40% -50%, thiab feem ntau ntawm cov kev cuam tshuam yuav raug xa ncaj qha mus rau cov pw tsaug zog thiab ballast txaj. Nyob rau hauv cov nqe lus ntawm kev nyuaj siab kis tau tus mob attenuation, gradient elastic ncoo tuaj yeem maj mam txo qhov cuam tshuam kev ntxhov siab los ntawm txoj kev tsheb ciav hlau los ntawm qhov pib 300MPa mus rau tsawg dua 50MPa ntawm qhov chaw pw tsaug zog, nrog kev ntxhov siab ntawm ntau dua 80%, tsis txhob pw tsaug zog tawg vim ntev - lub sij hawm siab. Qhov kev ntxhov siab ntawm cov ntaub qhwv ib txwm tsuas yog 30% -40%, thiab qhov kev ntxhov siab ntawm qhov chaw pw tsaug zog tseem nyob siab dua 150MPa, uas yooj yim ua rau cov neeg pw tsaug zog thaum ntxov. Nyob rau hauv cov nqe lus ntawm dynamic deformation, dynamic compression deformation ntawm gradient elastic pads yog tswj ntawm 3-5 hli, nrog uniform deformation thiab ceev elastic rov qab tsis tas yuav deformation. Txawm li cas los xij, qhov dynamic deformation ntawm cov ntaub qhwv ib txwm yog qhov loj heev (Ntau dua lossis sib npaug li 8 hli) ua rau kev poob ntawm txoj kab tsheb ciav hlau smoothness, los yog me me (tsawg dua los yog sib npaug li 2 hli) kom ua tau zoo buffering, thiab qhov deformation mus tas li yog ib qho yooj yim tshwm sim tom qab siv mus sij hawm ntev, uas ua rau kev ua haujlwm tsis tu ncua ntawm buffering. Tsis tas li ntawd, cov gradient elastic ncoo muaj kev qaug zog zoo dua. Tom qab 1 × 10⁸ dynamic impact tests, qhov elastic rov qab tus nqi tseem ntau dua los yog sib npaug rau 95%, thaum lub elastic rov qab tus nqi ntawm cov tsoos pads poob mus rau hauv qab 70% tom qab 2 × 10⁷ xeem.
Dab tsi yog txheej thickness adaptation yuav tsum tau ntawm gradient elastic nyob rau hauv -rail pads rau txawv kab ua hauj lwm tej yam kev mob?
Lub hauv paus ntawm txheej txheej thickness adaptation yuav tsum tau gradient elastic nyob rau hauv -rail pads rau txawv kab ua hauj lwm tej yam kev mob yog kho lub thickness ratio ntawm peb - txheej qauv kom phim lub qag load, kev khiav hauj lwm ceev thiab cuam tshuam cov yam ntxwv ntawm cov kab. Rau siab - cov kab tsheb ciav hlau ceev nrog kev ua haujlwm siab ceev, kev cuam tshuam ceev nrawm tab sis lub qag me me, tag nrho cov tuab ntawm cov ntaub ntawv hloov pauv yog 10 hli, suav nrog 2 hli tuab hnav- txheej tiv thaiv, 5 hli tuab tsis txheej thiab 3 hli tuab txheej txhawb nqa, tsom rau kev ntxiv dag zog rau qhov cuam tshuam kev nqus ntawm cov txheej txheem tsis zoo thiab kev tswj xyuas tib lub sijhawm. Rau hnyav- cov kab tsheb ciav hlau nrog lub qag loj thauj khoom thiab muaj zog cuam tshuam, tag nrho cov tuab ntawm cov ntaub qhwv tau zoo yog 15 hli, suav nrog 3 hli tuab hnav- txheej tiv thaiv, 7 hli tuab tsis txheej thiab 5 hli tuab txheej. Cov hnav- txheej tiv taus yog thickened los txhim kho shear thiab hnav tsis kam, thiab cov txheej tsis thiab cov txheej txheem yog thickened kom paub cov kauj ruam- los ntawm - kauj ruam buffering ntawm siab - muaj zog cuam tshuam thiab zam ballast txaj deformation. Rau qhov zoo tib yam - txoj kev tsheb ciav hlau ceev nrog nruab nrab qag load thiab ceev, tag nrho cov tuab ntawm cov ntaub qhwv tau hloov tau yog 12 hli, suav nrog 2.5 hli tuab hnav- txheej tiv thaiv, 6 hli tuab tsis txheej thiab 3.5 hli tuab txheej txhawb nqa, ntsuas kev ua haujlwm tsis zoo thiab siv tus nqi. Rau cov kab tsheb ciav hlau hauv nroog nrog nquag pib thiab nres thiab muaj zog rov ua dua ntawm lub log -rail cuam tshuam, tag nrho cov tuab ntawm cov ntaub ntawv hloov pauv yog 8 hli, suav nrog 2 hli tuab hnav- txheej tiv thaiv, 4 hli tuab tsis txheej thiab 2 hli tuab txheej. Cov txheej thickness piv yog optimized los txhim kho qaug zog tiv thaiv thiab hloov mus rau siab - zaus cuam tshuam rau kev ua haujlwm. Qhov dav ntawm lub ncoo nyob rau hauv tag nrho cov ua hauj lwm tej yam kev mob yog raws li nyob rau hauv lub dav dav ntawm txoj kev tsheb ciav hlau los xyuas kom meej tag nrho haum nrog lub tsheb ciav hlau.
Dab tsi yog cov txheej txheem tsim cov ntsiab lus tseem ceeb thiab cov qauv tswj kev ua tau zoo ntawm gradient elastic nyob rau hauv - tsheb ciav hlau pads?
Cov txheej txheem tsim cov ntsiab lus tseem ceeb ntawm gradient elastic nyob rau hauv -rail pads yog concentrated nyob rau hauvraw khoom piv, txheej vulcanization thiab tsim kub tswjlos xyuas kom meej qhov kev ua tau zoo sib xws ntawm peb - txheej txheej thiab interlayer bonding zoo. Cov khoom siv raw cov ntaub ntawv yuav tsum tau tswj kom meej raws li qhov yuav tsum tau ua ntawm txhua txheej: 15%-20% carbon dub ntxiv rau cov roj hmab nitrile ntawm hnav- txheej tiv thaiv los txhim kho hnav tsis kam; 10%. 5% -8% zinc oxide ntxiv rau cov roj hmab ntuj ntawm cov txheej txheem txhawb nqa kom ntseeg tau tias elastic rov ua haujlwm. Cov ntsiab lus impurity ntawm tag nrho cov ntaub ntawv raw yog tsawg dua los yog sib npaug li 0.5% kom tsis txhob cuam tshuam rau kev ua haujlwm ntawm roj hmab. Cov txheej txheem siv txheej txheem vulcanization txheej txheem: ua ntej, cov ntaub ntawv raw ntawm txhua txheej yog sib cais thiab calendered rau hauv cov ntaub ntawv roj hmab ntawm cov thickness, ces stacked nyob rau hauv qhov kev txiav txim ntawm hnav-resistant txheej, tsis txheej thiab kev them nyiaj yug txheej, muab tso rau hauv ib tug tshwj xeeb pwm rau high-temperature vulcanization. Lub vulcanization kub yog tswj ntawm 150-160 degree, vulcanization siab yog 10-12MPa, thiab lub sij hawm vulcanization yog 20-25 feeb los xyuas kom meej tag nrho fusion ntawm interlayer molecules thiab paub ib tug tseem ceeb txoj kev. Nyob rau hauv cov nqe lus ntawm kev tswj cov qauv zoo, lub interlayer bonding zog ntawm lub tiav lawm ncoo yuav tsum ntau tshaj los yog sib npaug zos rau 1.5MPa yam tsis muaj delamination tom qab tev kuaj; Lub hardness sib txawv ntawm txhua txheej yog tsawg dua los yog sib npaug rau ± 2HA, thiab elastic modulus deviation yog tsawg dua los yog sib npaug rau ± 0.5MPa; qhov deformation mus tas li tom qab qhov kev ntsuam xyuas qhov cuam tshuam yog tsawg dua lossis sib npaug ntawm 0.3 hli, thiab qhov elastic rov qab tus nqi ntau dua lossis sib npaug li 95%; Tom qab kev laus kev xeem (70℃× 168h), qhov hardness hloov yog tsawg dua los yog sib npaug rau ± 5HA, thiab lub tensile zog tuav tus nqi yog ntau tshaj los yog sib npaug rau 80%. Qhov kev kuaj xyuas piv txwv ntawm txhua pawg ntawm cov ntaub qhwv tsis pub tsawg dua 3%, thiab tag nrho cov khoom tsis tsim nyog tau rov ua dua.
Dab tsi yog qhov ntawm - qhov chaw tso thiab hloov kho cov ntsiab lus ntawm gradient elastic nyob rau hauv - tsheb ciav hlau pads?
Qhov ntawm - qhov chaw tso thiab hloov kho ntawm gradient elastic nyob rau hauv - cov ntaub pua tsev yuav tsum tau tsom rautso kev taw qhia, haum tswj thiab kev laus nrhiav kom pomlos xyuas kom meej qhov kev ua si zoo ntawm buffering kev ua tau zoo. Ua ntej yuav nteg, ntxuav cov xeb, roj stains, gravel thiab lwm yam impurities nyob rau hauv qab ntawm lub tsheb ciav hlau thiab sab saum toj nto ntawm tus neeg pw tsaug zog kom paub meej tias qhov kev sib cuag nto yog tiaj tus thiab huv si, thiab xyuas cov tsos ntawm lub ncoo nyob rau tib lub sij hawm. Cov ntaub qhwv tsis muaj kab nrib pleb, delamination thiab cov ces kaum uas ploj lawm tuaj yeem siv tau. Thaum lub sij hawm tso, lubdirectional nteg txoj caiyuav tsum tau ua raws li: sab ntawm lub ncoo cim nrog "UP" fim rau hauv qab ntawm lub tsheb ciav hlau, thiab hnav- txheej tiv thaiv yog ze rau ntawm txoj kev tsheb ciav hlau. Rov qab tso yog nruj me ntsis txwv tsis pub, txwv tsis pub nws yuav ua rau kom ceev ceev ntawm lub ncoo thiab tsis ua hauj lwm buffering. Tom qab tso, txheeb xyuas qhov haum: qhov sib chwv qhov sib txawv ntawm lub ncoo thiab txoj kev tsheb ciav hlau / pw tsaug zog tsawg dua lossis sib npaug li 0.2 hli yam tsis muaj warping thiab hollowing. Yog tias muaj qhov sib txawv, ntxuav qhov chaw tiv tauj dua thiab kho qhov chaw ncoo. Kev tshuaj xyuas txhua hnub yog 6 lub hlis, tsom rau kev kuaj xyuas seb lub ncoo puas muaj kev laus, tawg, delamination lossis deformation mus tas li. Yog hais tias lub ncoo nto muaj qhov tawg ntev Ntau dua lossis sib npaug li 5 hli, thaj tsam delamination Ntau dua lossis sib npaug rau 10cm² lossis qhov deformation tas li Ntau dua lossis sib npaug li 0.5 hli, nws yuav tsum tau hloov lub sijhawm. Thaum hloov lub ncoo, ua ntej loosen lub fastener system, me ntsis nqa txoj kev tsheb ciav hlau los ntawm 3-5mm, tshem tawm lub qub ncoo thiab ntxuav qhov chaw tiv tauj, ces muab tso rau hauv lub ncoo tshiab kom ntseeg tau tias lub ncoo nyob nruab nrab tsis muaj offset. Recheck lub rail smoothness tom qab reset lub fastener system, nrog rau qhov siab sib txawv tsawg dua los yog sib npaug zos rau 0.3 hli. Tsis tas li ntawd, nyob rau hauv qhov chaw ntub dej thiab corrosive xws li los nag thiab cov ntug hiav txwv dej, siv cov tshuaj tiv thaiv kev laus ntawm lub ncoo kom ntev lub neej kev pab cuam ntawm lub ncoo.