Asphalt Kub Npaum Li Cas Tawm Ntawm Lub Hoobkas Thiab Vim Li Cas Cov Neeg Ua Haujlwm Paving Yuav Tsum Saib Xyuas?
Yog li, Asphalt kub npaum li cas los ntawm cov nroj tsuag?
Yog tias koj tau sawv ze li kaum feet ntawm lub tsheb thauj khoom tshiab, koj twb paub cov lus teb hauv koj pob txha lawm: kub . Tab sis "kub" tsis yog ib qho spec uas koj tuaj yeem muab tso rau ntawm daim ntawv pov thawj. Cov lej tseem ceeb. Cov asphalt sib tov kub (HMA) ib txwm tso lub nruas sib tov ntawm280–330 °F (138–166 °C) . Lub qhov rais ntawd tsis yog qhov tsis raws cai; nws yog qhov chaw zoo uas cov binder nplaum txaus kom npog txhua lub pob zeb tab sis kua txaus kom cov khoom sib tov ua haujlwm tau rau kev thauj, kev tso, thiab kev sib zog. Tso qis dua 260 °F thiab koj yuav muaj kev pheej hmoo ntawm cov khoom sib tov mos; nce siab tshaj 340 °F thiab cov kua asphalt pib oxidizing sai - koj txoj kev tshiab yuav laus ntau xyoo hauv feeb.
Dab tsi tswj qhov kub tawm ntawd?
Peb lub levers txiav txim siab qhov nyeem ntawm daim pib tsheb thauj khoom: cov dej noo sib xyaw, qib binder, thiab lub sijhawm khaws cia silo . Pob zeb ntub ua haujlwm zoo li lub paj rwb, nyiag BTUs ntawm lub nplaim taws burner. Ib tug neeg ua haujlwm hauv North Carolina ib zaug hais rau kuv tias, "Txhua ib feem pua ntawm cov dej noo ua rau peb raug nqi 14 ° F ntawm lub rooj vag." Lub caij no, PG 76-22 polymer-modified binder xav tau cua sov ntxiv kom ntws, tab sis koj tsis tuaj yeem tsuas yog tig lub burner vim tias roj hmab overheated tuaj yeem sib cais. Thaum kawg, cov khoom sib xyaw tsis tuaj yeem zaum hauv silo ntev dhau; tom qab plaub teev nws poob kwv yees li 5 ° F ib teev txawm tias nyob hauv cov thoob khib nyiab insulated. Ntxiv cov hloov pauv no ua ke thiab koj yuav pom vim li cas lub chaw kuaj mob cog khaws lub ntsuas kub laser taw rau ntawm txoj siv sia zoo li nws yog qhov chaw tso tawm.
Vim li cas Lub Tsheb Thauj Khoom Tsis Txias Qhov Sib Xyaws Sai Li Koj Xav
Cov neeg tsav tsheb cog lus tias qhov khoom thauj "poob 50 degrees ntawm kev tsav tsheb nees nkaum feeb," tab sis cov thermocouple probes qhia txog zaj dab neeg sib txawv. Kev poob cua sov yog tswj hwm los ntawm thaj chaw saum npoo, tsis yog ntim . Lub thawv pov tseg 22-tuj uas zoo li lub ncuav mog qab zib tsuas muaj 8% ntawm nws qhov hnyav raug rau huab cua. Cov txaj pw thiab cov ntaub thaiv cua sov txo qhov poob hluav taws xob los ntawm lwm 30%. Cov ntaub ntawv tiag tiag los ntawm FHWA's Mobile Asphalt Pavement Monitor (MAPM) qhia txog qhov nruab nrab poob ntawm 7–12 ° F hauv 30 feeb thawj zaug - tseem nyob hauv qhov tshwj xeeb rau feem ntau lub xeev DOTs. Qhov coj mus? Tsis txhob liam qhov deb ntawm kev thauj khoom rau cov pob qij txha txias; liam qhov tsis zoo ntawm cov ntaub thaiv cua sov lossis kev hloov pauv tsis muaj npog.
Tus Nqi Zais Cia ntawm Kev Khiav Txias Dhau
Thaum cov khoom sib xyaws tuaj txog qis dua 275 ° F, cov neeg ua haujlwm yuav ntsib teeb meem ntau yam:
- Txo qhov sib koom ua ke - cov npoo txias tsis xaws, cia dej nkag mus rau hauv qab daim lev.
- Lub sijhawm dov luv dua - koj muaj tej zaum rau zaug dhau ua ntej qhov sib tov poob qis dua 175 ° F, qhov tsawg kawg nkaus rau kev sib zog ua haujlwm zoo.
- Kev tawg yav tom ntej - txhua 1% poob hauv cov qhov cua tshaj 8% tuaj yeem ua rau lub neej qaug zog luv dua ib nrab, raws li kev tshawb fawb NCAT.
Hauv lus yooj yim, "kev txuag roj" ntawm lub Hoobkas tuaj yeem raug nqi ntau dua kaum npaug rau kev kho ua ntej lub sijhawm. Ib txoj kev tshawb fawb DOT tau muab tus nqi ntawm kev sib cais qis qis ntawm $ 2.8 lab rau ib txoj kab-mais dhau kaum tsib xyoos lub neej.
Yuav Ua Li Cas Khaws Qhov Kub Rau Qhov Koj Xav Tau
Zoo hmoo, koj tsis tau daig tab sis koj yuav tsum ua siab ntev. Nov yog plaub txoj kev uas koj tau sim ua ntej lawm:
1. Lub Koob Yees Duab Kub ntawm Lub Pob Zeb
Tso lub FLIR A700 rau saum lub auger thiab koj yuav pom cov xim sib txawv tam sim ntawd. Qhov sib txawv 20 ° F hla lub screed yog lub cim liab uas kev sib cais tab tom tshwm sim ua ntej koj lub qhov muag. Cov neeg ua haujlwm tuaj yeem kho qhov qhib rooj vag lossis remix ntawm tus kheej es tsis txhob pom nws ib mais tom qab.
2. Cov Khoom Siv Ntxiv Sov Sov Tsis Yog Rau Cov Ntsiab Lus Ntsuab Xwb
Cov tshuaj asphalt-blooming surfactants zoo li Sasobit txo qhov ua haujlwm tau los ntawm 30–40 °F yam tsis muaj kev cuam tshuam rau qhov tawv. Qhov ntawd txhais tau tias koj tuaj yeem thauj mus ntxiv lossis ua kom tiaj tiaj rau 50 °F hnub thaum tseem muaj qhov ntom ntom. Qhov zoo ntxiv: pa luam yeeb xiav tsawg dua ntawm lub Hoobkas, ua rau cov neeg zej zog (thiab cov neeg tswj hwm) zoo siab.
3. Cov Txaj Tsheb Thauj Khoom Uas Muaj Sov - Yog, Lawv Them Rau Lawv Tus Kheej
Ib daim phiaj propane hauv qab txaj ntxiv 18 lbs rau qhov hnyav tare tab sis khaws cov khoom thauj saum 290 °F rau ntxiv 45 feeb. Ntawm $ 0.40 ib lub thermo, qhov ntawd yog qis dua $ 4 rau ib lub tsheb thauj khoom kom yuav ib nrab teev ntxiv ntawm kev compactability. Ntawm 10,000-tuj hauv nroog hmo ntuj, lej sib npaug li $ 0.12 ib tuj - pheej yig dua li ib tuj ntawm do-over patch.
4. Kev Sib Koom Cov Ntaub Ntawv Tam Sim No
Cov nroj tsuag niaj hnub no tuaj yeem thawb qhov ntsuas kub ncaj qha mus rau ib lub app uas tus thawj tswj xyuas kev tswj xyuas zoo, tus neeg ua haujlwm paver, thiab tus thawj coj roller sib koom. Thaum qhov kub sib tov poob qis dua qhov teev tseg, cov ntawv ceeb toom thawb ua rau muaj kev kuaj xyuas qhov ceev tam sim ntawd. Ib lub nroog Wisconsin tau txo nws feem pua ntawm kev rov ua dua los ntawm 4.2% mus rau 0.9% hauv ib lub caij siv cov txheej txheem no.
Tab sis puas yog qhov kub sib xyaw ua ke txhais tau tias muaj ntau qhov pa phem?
Nws yog ib lo lus nug ncaj ncees. Tus qauv AP-42 ntawm EPA qhia tias txhua qhov nce 10 °F tso tawm kwv yees li 2% ntau CO₂ ntawm lub pawg. Txawm li cas los xij, kev tshuaj xyuas lub neej ntawm kev lag luam qhia tau tias qhov ceev zoo dua hauv qhov chaw them rov qab rau cov pa phem ntawd los ntawm kev ncua lub neej ntawm txoj kev. Hauv ntej, 3% nce hauv CO₂ ntawm tsob nroj tuaj yeem tiv thaiv 30% ntawm kev rov ua dua tshiab tom qab. Net-net, cov pa roj carbon ledger tsis zoo - tsawg dua kev sib tsoo, kev thauj khoom, thiab rov ua kom sov dua ntau xyoo. Ntxiv mus, cov thev naus laus zis sib xyaw sov tuaj yeem txo qhov kub ntawm lub cub tawg 35 °F thaum khaws cia kev ua haujlwm, txo ob qho tib si NOx thiab CO hauv ib qho kev txav mus los.
Daim Ntawv Teev Npe Sai rau Cov Kws Sau Ntawv Tshwj Xeeb
Yog tias koj hloov kho DOT cov lus qhia, xav txog cov mos txwv no:
- Yuav tsum tau siv infrared kub profiling tas mus li ntawm daim lev paver.
- Teem qhov kub xa khoom tsawg kawg nkaus ntawm 275 ° F rau 9.5 hli sib tov, 285 ° F rau 19 hli puag.
- Cia kom sov sib tov txog 240 °F yog tias qhov ceev tau txheeb xyuas nrog cov cores ntawm 96% theoretical max.
- Khaws cia rau hauv lub hau silo rau peb teev tshwj tsis yog tias siv cov roj inert-gas blanketing.
Thiab hey, tsis muaj leej twg muaj sijhawm rau cov khoom noj txias thaum tsheb khiav ntau mais.
Cov Lus Qhia Tseem Ceeb
Kev paub tias cov asphalt kub npaum li cas tawm ntawm lub Hoobkas tsis yog qhov tsis tseem ceeb - nws yog qhov tseem ceeb uas xauv qhov ceev, qhov zoo ntawm kev caij tsheb, thiab, thaum kawg, tus nqi them se. Qhia qhov kub thiab txias kom raug, tiv thaiv nws zoo li tus noog thaum lub sijhawm thauj khoom, thiab koj txoj kev taug kev yuav nyob ntev dua cov nom tswv uas tau pab nyiaj rau nws.
