Cellulose ether cuam tshuam rau kev tuav dej

Txoj kev simulation ib puag ncig tau siv los kawm txog cov txiaj ntsig ntawm cellulose ethers nrog ntau qib kev hloov pauv thiab molar hloov pauv ntawm cov dej khaws cia ntawm mortar nyob rau hauv cov xwm txheej kub. Kev soj ntsuam ntawm cov txiaj ntsig kev sim siv cov cuab yeej txheeb cais qhia tau hais tias hydroxyethyl methyl cellulose ether nrog qib qis hloov pauv thiab qib siab molar hloov pauv qhia tau hais tias qhov dej khaws cia zoo tshaj plaws hauv mortar.

Cov lus tseem ceeb: cellulose ether: dej tuav; mortar; ib puag ncig simulation txoj kev; kub tej yam kev mob

Vim nws qhov zoo ntawm kev tswj xyuas kom zoo, kev yooj yim ntawm kev siv thiab kev thauj mus los, thiab kev tiv thaiv ib puag ncig, cov tshuaj khib nyiab qhuav yog tam sim no ntau dua thiab dav siv hauv kev tsim vaj tsev. Cov tshuaj khib nyiab qhuav yog siv tom qab ntxiv dej thiab sib tov ntawm qhov chaw tsim kho. Dej muaj ob lub luag haujlwm tseem ceeb: ib qho yog los xyuas kom meej qhov kev tsim kho ntawm cov mortar, thiab lwm yam yog los xyuas kom meej lub hydration ntawm cov cementitious cov ntaub ntawv kom cov mortar ua tau raws li qhov yuav tsum tau ntawm lub cev thiab txhua yam khoom tom qab hardening. Los ntawm kev ua tiav ntawm kev ntxiv dej rau hauv mortar mus rau qhov ua tiav ntawm kev tsim kho kom tau txais cov khoom siv lub cev thiab cov khoom siv zoo, cov dej dawb yuav tsiv mus nyob rau hauv ob qho kev qhia ntxiv rau hydrating cov cement: puag txheej nqus thiab evaporation nto. Nyob rau hauv tej yam kev mob kub los yog nyob rau hauv ncaj qha tshav ntuj, noo noo evaporates sai sai ntawm qhov chaw. Nyob rau hauv cov xwm txheej kub los yog nyob rau hauv tshav ntuj ncaj qha, nws yog ib qho tseem ceeb uas cov mortar khaws cov dej noo sai sai ntawm qhov chaw thiab txo nws cov dej dawb. Tus yuam sij rau kev ntsuam xyuas cov dej tuav ntawm mortar yog los txiav txim siab txog txoj kev sim tsim nyog. Li Wei et al. tau kawm txog txoj kev sim ntawm mortar dej tuav thiab pom tias piv nrog lub tshuab nqus tsev filtration method thiab lim ntawv, txoj kev simulation ib puag ncig tuaj yeem ua tau zoo rau cov dej tuav ntawm mortar ntawm qhov sib txawv ambient kub.

Cellulose ether yog cov khoom siv dej ntau tshaj plaws hauv cov khoom siv khib nyiab qhuav. Feem ntau siv cellulose ethers nyob rau hauv qhuav sib tov mortar yog hydroxyethyl methyl cellulose ether (HEMC) thiab hydroxypropyl methyl cellulose ether (HPMC). Cov pab pawg sib raug zoo yog hydroxyethyl, methyl thiab hydroxypropyl, methyl. Qib ntawm kev hloov pauv (DS) ntawm cellulose ether qhia txog qib uas pawg hydroxyl ntawm txhua chav anhydroglucose hloov pauv, thiab qib ntawm molar hloov pauv (MS) qhia tias yog tias pawg hloov pauv muaj cov pab pawg hydroxyl, cov tshuaj hloov pauv txuas ntxiv mus. nqa tawm cov tshuaj tiv thaiv etherification los ntawm pab pawg dawb hydroxyl tshiab. degree. Cov qauv tshuaj thiab qib ntawm kev hloov pauv ntawm cellulose ether yog ib qho tseem ceeb cuam tshuam rau kev thauj mus los ntawm cov dej hauv mortar thiab microstructure ntawm mortar. Qhov nce ntawm qhov hnyav molecular ntawm cellulose ether yuav ua rau kom cov dej khaws cia ntawm mortar, thiab qhov sib txawv ntawm kev hloov pauv yuav cuam tshuam rau cov dej tuav ntawm mortar.

Lub ntsiab yam tseem ceeb ntawm qhov chaw qhuav-sib xyaw mortar tsim muaj xws li ambient kub, txheeb ze humidity, cua ceev thiab los nag. Hais txog huab cua kub, ACI (American Concrete Institute) Pawg Neeg Saib Xyuas 305 txhais tias nws yog ib qho kev sib xyaw ua ke xws li huab cua kub, tsis tshua muaj neeg txheeb ze, thiab cua ceev, uas cuam tshuam qhov zoo lossis kev ua haujlwm ntawm cov pob zeb tshiab lossis tawv tawv ntawm cov huab cua no. Lub caij ntuj sov hauv kuv lub teb chaws feem ntau yog lub caij ntuj sov rau kev tsim kho ntawm ntau yam kev tsim kho. Kev tsim kho nyob rau hauv ib qho kev kub ntxhov nrog kub thiab av noo tsawg, tshwj xeeb tshaj yog ib feem ntawm cov mortar qab phab ntsa yuav raug tshav ntuj, uas yuav cuam tshuam rau cov tshiab mixing thiab hardening ntawm qhuav mortar. Cov teebmeem tseem ceeb ntawm kev ua haujlwm xws li txo qis kev ua haujlwm, lub cev qhuav dej thiab tsis muaj zog. Yuav ua li cas los xyuas kom meej qhov zoo ntawm qhuav-sib tov mortar nyob rau hauv kub kev nyab xeeb kev tsim kho tau nyiam cov xim thiab kev tshawb fawb ntawm mortar kev lag luam kws txawj thiab cov neeg ua hauj lwm tsim.

Nyob rau hauv daim ntawv no, ib puag ncig simulation txoj kev yog siv los soj ntsuam cov dej tuav ntawm mortar tov nrog hydroxyethyl methyl cellulose ether thiab hydroxypropyl methyl cellulose ether nrog txawv degrees ntawm kev hloov thiab molar hloov ntawm 45℃, thiab cov ntaub ntawv pov thawj yog siv JMP8.02 tshuaj xyuas cov ntaub ntawv xeem los kawm txog kev cuam tshuam ntawm cov cellulose ethers sib txawv ntawm cov dej tuav cov tshuaj khib hauv cov dej kub.

1. Cov ntaub ntawv raw thiab cov txheej txheem xeem

1.1 Cov khoom siv raw

Conch P. 042.5 Cement, 50-100 mesh quartz xuab zeb, hydroxyethyl methylcellulose ether (HEMC) thiab hydroxypropyl methylcellulose ether (HPMC) nrog viscosity ntawm 40000mPa·s. Txhawm rau kom tsis txhob muaj kev cuam tshuam ntawm lwm cov khoom, qhov kev sim no siv cov tshuaj mortar yooj yim, suav nrog 30% cement, 0.2% cellulose ether, thiab 69.8% quartz xuab zeb, thiab cov dej ntxiv yog 19% ntawm tag nrho cov tshuaj mortar. Ob leeg yog pawg loj.

1.2 Environmental simulation method

Cov cuab yeej sim ntawm ib puag ncig simulation txoj kev siv iodine-tungsten teeb, kiv cua, thiab ib puag ncig chamber simulate sab nraum zoov kub, av noo, thiab cua ceev, thiab lwm yam., los ntsuam xyuas qhov sib txawv ntawm qhov zoo ntawm freshly mix mortar nyob rau hauv txawv tej yam kev mob, thiab rau sim cov dej tuav ntawm lub mortar. Hauv qhov kev sim no, txoj kev sim hauv cov ntaub ntawv tau raug txhim kho, thiab lub khoos phis tawj txuas nrog qhov sib npaug rau kev kaw lus tsis siv neeg thiab kev sim, yog li txo qhov kev sim ua yuam kev.

Qhov kev ntsuam xyuas tau ua nyob rau hauv ib qho kev sim ntsuas [kub (23±2)°C, txheeb ze humidity (50±3)%] siv cov txheej txheem tsis nqus dej (cov tais yas nrog ib txoj kab uas hla ntawm 88mm) ntawm qhov kub thiab txias ntawm 45°C. Txoj kev xeem yog raws li nram no:

(1) Nrog lub kiv cua tua, tig lub teeb iodine-tungsten, thiab muab cov tais yas tso rau hauv qhov chaw ruaj khov vertically hauv qab lub teeb iodine-tungsten kom preheat rau 1 h;

(2) Ntsuas lub tais yas, tom qab ntawd muab cov tshuaj khib nyiab tso rau hauv lub tais yas, du nws raws li qhov yuav tsum tau ua, thiab ces ntsuas nws;

(3) Muab cov tais yas rov qab mus rau nws qhov qub, thiab cov software tswj qhov sib npaug kom tau txais qhov hnyav ib zaug txhua 5 feeb, thiab qhov kev xeem xaus tom qab 1 teev.

2. Cov txiaj ntsig thiab kev sib tham

Kev suav cov txiaj ntsig ntawm dej tuav tus nqi R0 ntawm mortar tov nrog sib txawv cellulose ethers tom qab irradiation ntawm 45°C rau 30 min.

Cov ntaub ntawv soj ntsuam saum toj no tau txheeb xyuas siv cov khoom JMP8.02 ntawm pawg software txheeb cais SAS Tuam Txhab, txhawm rau kom tau txais cov txiaj ntsig kev txheeb xyuas txhim khu kev qha. Cov txheej txheem tsom xam yog raws li nram no.

2.1 Regression tsom xam thiab haum

Qauv haum tau ua los ntawm tus qauv yam tsawg kawg nkaus squares. Kev sib piv ntawm tus nqi ntsuas thiab tus nqi kwv yees qhia tau hais tias qhov kev ntsuam xyuas ntawm tus qauv haum, thiab nws yog tag nrho tso tawm graphically. Ob txoj kab nkhaus sawv cev rau "95% kev ntseeg siab ib ntus", thiab kab rov tav dashed sawv cev rau tus nqi nruab nrab ntawm tag nrho cov ntaub ntawv. Qhov nkhaus nkhaus thiab qhov kev sib tshuam ntawm cov kab rov tav kab qhia tias tus qauv pseudo-theem yog qhov raug.

Cov nqi tshwj xeeb rau cov ntsiab lus haum thiab ANOVA. Nyob rau hauv cov ntsiab lus zoo, R² mus txog 97%, thiab P tus nqi hauv kev txheeb xyuas qhov sib txawv yog tsawg dua 0.05. Kev sib xyaw ua ke ntawm ob qho xwm txheej ntxiv qhia tau tias tus qauv haum yog qhov tseem ceeb.

2.2 Kev soj ntsuam ntawm cov xwm txheej cuam tshuam

Nyob rau hauv lub Scope ntawm qhov kev sim no, nyob rau hauv cov xwm txheej ntawm 30 feeb ntawm irradiation, qhov haum ntawm cov yam ntxwv yog raws li nram no: nyob rau hauv cov nqe lus ntawm ib qho tseem ceeb, p qhov tseem ceeb tau los ntawm hom cellulose ether thiab molar hloov degree yog tag nrho cov tsawg tshaj li 0.05. , uas qhia tau hais tias qhov thib ob Lub tom kawg muaj kev cuam tshuam loj heev rau cov dej tuav ntawm lub mortar. Raws li qhov kev cuam tshuam kev cuam tshuam, los ntawm kev sim cov txiaj ntsig ntawm qhov kev soj ntsuam zoo ntawm qhov cuam tshuam ntawm hom cellulose ether, qib ntawm kev hloov pauv (Ds) thiab qib ntawm molar hloov pauv (MS) ntawm cov dej tuav ntawm mortar, hom cellulose ether thiab qib ntawm kev hloov pauv, Kev sib cuam tshuam ntawm qib ntawm kev hloov pauv thiab molar degree ntawm kev hloov pauv muaj qhov cuam tshuam tseem ceeb ntawm cov dej tuav ntawm mortar, vim tias p-values ​​ntawm ob qho tib si tsawg dua 0.05. Kev sib cuam tshuam ntawm yam qhia tau hais tias kev sib cuam tshuam ntawm ob yam yog piav qhia ntau dua. Tus ntoo khaub lig qhia tias ob qho tib si muaj kev sib raug zoo, thiab qhov sib luag qhia tias ob qho tib si muaj kev sib raug zoo. Hauv daim duab qhia kev sib cuam tshuam, coj qhov chawα qhov twg hom ntsug thiab cov lateral hloov degree sib cuam tshuam raws li piv txwv, ob kab ntu sib tshuam, qhia tias kev sib raug zoo ntawm hom thiab qib kev hloov pauv muaj zog, thiab hauv cheeb tsam b qhov chaw ntsug thiab molar lateral hloov degree Kev sib cuam tshuam, ob kab ntu zoo li sib npaug, qhia tias kev sib raug zoo ntawm hom thiab molar hloov pauv tsis muaj zog.

2.3 Kev kwv yees kev tuav dej

Raws li tus qauv haum, raws li kev cuam tshuam ntawm cov cellulose ethers sib txawv ntawm cov dej tuav ntawm cov tshuaj khib nyiab, cov dej tuav ntawm cov tshuaj khib yog kwv yees los ntawm JMP software, thiab qhov sib xyaw ua ke rau qhov zoo tshaj plaws dej tuav ntawm mortar yog pom. Cov dej tuav pov thawj qhia tau hais tias kev sib xyaw ua ke ntawm cov dej khib nyiab zoo tshaj plaws thiab nws txoj kev txhim kho, uas yog, HEMC zoo dua li HPMC hauv hom kev sib piv, qhov nruab nrab thiab qis hloov pauv zoo dua li kev hloov pauv siab, thiab qhov nruab nrab thiab siab hloov pauv zoo dua li kev hloov qis. nyob rau hauv molar hloov, tab sis Tsis muaj qhov sib txawv ntawm ob qho tib si hauv kev sib xyaw ua ke no. Hauv cov ntsiab lus, hydroxyethyl methyl cellulose ethers nrog qib qis hloov pauv thiab qib siab molar hloov tau pom qhov zoo tshaj plaws mortar dej tuav ntawm 45℃. Raws li kev sib xyaw ua ke, qhov kwv yees tus nqi ntawm cov dej tuav tau muab los ntawm qhov system yog 0.611736±0.014244 ib.

3. Cov lus xaus

(1) Raws li ib qho tseem ceeb tshaj plaws, hom cellulose ether muaj qhov cuam tshuam loj rau cov dej tuav ntawm mortar, thiab hydroxyethyl methyl cellulose ether (HEMC) zoo dua li hydroxypropyl methyl cellulose ether (HPMC). Nws qhia tau hais tias qhov sib txawv ntawm hom kev hloov pauv yuav ua rau qhov sib txawv ntawm cov dej tuav. Nyob rau tib lub sijhawm, hom cellulose ether kuj cuam tshuam nrog qib kev hloov pauv.

(2) Raws li ib qho tseem ceeb ntawm kev cuam tshuam qhov cuam tshuam, molar hloov qib ntawm cellulose ether txo qis, thiab cov dej tuav ntawm mortar yuav txo qis. Qhov no qhia tau hais tias raws li sab saw ntawm cellulose ether substituent pab pawg neeg txuas ntxiv mus rau etherification cov tshuaj tiv thaiv nrog cov dawb hydroxyl pab pawg neeg, nws kuj yuav ua rau qhov sib txawv ntawm cov dej tuav ntawm mortar.

(3) Kev hloov pauv ntawm cellulose ethers cuam tshuam nrog hom thiab molar degree ntawm kev hloov pauv. Nyob nruab nrab ntawm qhov kev hloov pauv thiab hom, nyob rau hauv cov ntaub ntawv ntawm cov qib qis ntawm kev hloov pauv, cov dej tuav ntawm HEMC zoo dua li ntawm HPMC; nyob rau hauv cov ntaub ntawv ntawm high degree ntawm kev hloov, qhov sib txawv ntawm HEMC thiab HPMC tsis loj. Rau kev sib cuam tshuam ntawm qib ntawm kev hloov pauv thiab molar hloov pauv, nyob rau hauv cov ntaub ntawv ntawm cov qib qis ntawm kev hloov pauv, cov dej khaws cia ntawm cov qib molar ntawm kev hloov pauv yog qhov zoo dua li qhov siab molar degree ntawm kev hloov pauv; Qhov txawv tsis yog loj.

(4) Lub mortar tov nrog hydroxyethyl methyl cellulose ether nrog cov qib qis hloov pauv thiab qib siab molar hloov tau pom tias cov dej tuav tau zoo tshaj plaws nyob rau hauv qhov kub. Txawm li cas los xij, yuav ua li cas piav qhia txog cov txiaj ntsig ntawm cellulose ether hom, qib ntawm kev hloov pauv thiab molar degree ntawm kev hloov pauv ntawm cov dej khaws cia ntawm cov tshuaj khib nyiab, qhov teeb meem ntawm kev siv tshuab hauv qhov no tseem xav tau kev kawm ntxiv.