Hydroxypropyl methylcellulose ether ntawm cov khoom ntawm yoov tshauv mortar

Cov nyhuv ntawm hydroxypropyl methylcellulose ether ntawm cov khoom ntawm yoov tshauv mortar tau kawm, thiab kev sib raug zoo ntawm ntub ntom ntom thiab compressive zog tau soj ntsuam. Cov txiaj ntsig kev sim qhia tau hais tias ntxiv hydroxypropyl methylcellulose ether rau ya tshauv mortar tuaj yeem txhim kho cov dej khaws cia ntawm cov tshuaj khib nyiab, ua kom lub sijhawm sib txuas ntawm cov mortar, thiab txo qhov ntub dej thiab compressive zog ntawm cov tshuaj khib. Muaj kev sib raug zoo ntawm qhov ntub dej thiab 28d compressive zog. Nyob rau hauv cov xwm txheej ntawm kev paub ntub dej ntom ntom, 28d compressive zog tuaj yeem suav tau los ntawm kev siv cov qauv tsim nyog.

Cov lus tseem ceeb:ya tshauv; cellulose ether; tuav dej; compressive zog; kev sib raug zoo

Tam sim no, ya tshauv tau dav siv hauv kev tsim kho engineering. Ntxiv qee cov hmoov tshauv ya mus rau hauv mortar tuaj yeem tsis tsuas yog txhim kho cov khoom siv dag zog thiab kav ntev ntawm mortar, tab sis kuj txo tus nqi ntawm mortar. Txawm li cas los xij, ya tshauv mortar qhia tau hais tias tsis muaj dej tuav, yog li yuav ua li cas txhim kho cov dej tuav ntawm mortar tau dhau los ua qhov teeb meem tseem ceeb uas yuav tsum tau daws. Cellulose ether yog cov khoom siv ua haujlwm siab uas feem ntau siv hauv tsev thiab txawv teb chaws. Nws tsuas yog yuav tsum tau ntxiv rau me me kom muaj kev cuam tshuam zoo rau cov ntsuas kev ua haujlwm xws li dej tuav thiab compressive zog ntawm mortar.

1. Cov ntaub ntawv raw thiab cov txheej txheem xeem

1.1 Cov khoom siv raw

Cov cement yog P·O 42.5 qib zoo tib yam Portland cement tsim los ntawm Hangzhou Meiya Cement Factory; ya tshauv yog qibⅡtshauv; Cov xuab zeb yog cov xuab zeb nruab nrab zoo tib yam nrog kev ua kom zoo ntawm 2.3, qhov ntom ntom ntawm 1499kg·m-3, thiab noo noo ntawm 0.14%, av nkos 0.72%; hydroxypropyl methyl cellulose ether (HPMC) yog tsim los ntawm Shandong Heda Co., Ltd., lub hom yog 75HD100000; cov dej sib tov yog dej kais dej.

1.2 Kev npaj mortar

Thaum sib tov cellulose ether hloov mortar, thawj zaug sib tov HPMC nrog cov cement thiab ya tshauv kom huv si, ces qhuav sib tov nrog xuab zeb rau 30 vib nas this, ces ntxiv dej thiab sib tov tsis pub tsawg tshaj 180 vib nas this.

1.3 Test method

Qhov xwm txheej tsis sib xws, ntub dej, delamination thiab teeb lub sij hawm ntawm cov kev sib xyaw ua ke hauv jgj70-90 "Kev ntsuas kev coj ua ntawm lub tsev cug". Kev tuav dej ntawm mortar yog txiav txim siab raws li txoj kev sim rau kev tuav dej ntawm mortar hauv Appendix A ntawm JG / T 230-2007 "Ready Mixed Mortar". Lub zog compressive xeem tau txais 70.7mm x 70.7mm x 70.7mm lub voos xwmfab bottomed kuaj pwm. Qhov kev sim tsim thaiv yog kho ntawm qhov kub ntawm (20±2)°C rau 24 teev, thiab tom qab demoulding, nws yog txuas ntxiv mus kho nyob rau hauv ib puag ncig nrog kub ntawm (20±2)°C thiab tus txheeb ze av noo siab tshaj 90% rau lub hnub nyoog predetermined, raws li JGJ70-90 "Building Mortar Basic kev xeem txoj kev "kev txiav txim siab ntawm nws compressive zog.

2. Cov txiaj ntsig thiab kev tshuaj xyuas

2.1 ntub dej ntom ntom

Nws tuaj yeem pom los ntawm kev sib raug zoo ntawm qhov ceev thiab tus nqi HPMC uas cov kev ntub dej maj mam txo qis dua nrog qhov nce ntawm HPMC. Thaum tus nqi ntawm HPMC yog 0.05%, qhov ntub dej ntawm cov tshuaj khib nyiab yog 96.8% ntawm cov tshuaj khib nyiab. Thaum tus nqi ntawm HPMC tseem nce ntxiv, Qhov txo qis ntawm qhov ntub dej nrawm nrawm. Thaum cov ntsiab lus ntawm HPMC yog 0.20%, qhov ntub dej ntawm cov mortar tsuas yog 81.5% ntawm qhov ntsuas qhov ntsuas. Qhov no feem ntau yog vim huab cua nkag los ntawm HPMC. Cov cua npuas ua kom cov porosity ntawm lub mortar thiab txo cov compactness, uas ua rau txo qhov ntim ntawm cov mortar.

2.2 Teem sijhawm

Nws tuaj yeem pom los ntawm kev sib raug zoo ntawm lub sijhawm coagulation thiab tus nqi ntawm HPMC tias lub sijhawm coagulation yog maj mam nce. Thaum qhov ntau npaum li cas yog 0.20%, lub sijhawm teem sijhawm nce los ntawm 29.8% piv nrog cov tshuaj khib nyiab, ncav cuag li 300min. Nws tuaj yeem pom tias thaum noj ntau npaum li 0.20%, lub sijhawm teeb tsa muaj qhov hloov pauv zoo. Yog vim li cas L Schmitz li al. ntseeg tias cellulose ether molecules feem ntau yog adsorbed ntawm cov khoom siv dej xws li cSH thiab calcium hydroxide, thiab tsis tshua muaj adsorbed ntawm thawj theem ntxhia ntawm clinker. Tsis tas li ntawd, vim qhov nce hauv viscosity ntawm pore tov, cellulose ether txo. Kev txav mus los ntawm ions (Ca2+, so42-…) nyob rau hauv cov pore tov ntxiv ncua cov txheej txheem hydration.

2.3 Txheej thiab tuav dej

Ob qho tib si qib ntawm delamination thiab dej tuav tuaj yeem ua rau cov dej tuav cov nyhuv ntawm mortar. Los ntawm kev sib raug zoo ntawm qib ntawm delamination thiab tus nqi ntawm HPMC, nws tuaj yeem pom tau tias qhov degree ntawm delamination qhia tau tias txo qis dua li qhov HPMC nce ntxiv. Thaum cov ntsiab lus ntawm HPMC yog 0.05%, qhov degree ntawm delamination txo qis heev, qhia tau hais tias thaum cov ntsiab lus ntawm fiber ntau ether me me, cov degree ntawm delamination tuaj yeem txo qis heev, cov nyhuv ntawm cov dej tuav tau tuaj yeem txhim kho, thiab kev ua haujlwm tau zoo. workability ntawm mortar tuaj yeem txhim kho. Kev txiav txim los ntawm kev sib raug zoo ntawm cov cuab yeej dej thiab tus nqi ntawm HPMC, raws li tus nqi ntawm HPMC nce, cov dej tuav kuj maj mam zoo dua. Thaum qhov ntau npaum li cas tsawg dua 0.15%, cov dej tuav cov nyhuv nce maj mam, tab sis thaum cov koob tshuaj nce mus txog 0.20%, cov dej tuav tau zoo heev, los ntawm 90.1% thaum noj ntau npaum li 0.15%, mus txog 95%. Tus nqi ntawm HPMC tseem nce ntxiv, thiab kev tsim kho ntawm mortar pib deterioration. Yog li, txiav txim siab txog kev tuav dej thiab kev tsim kho, qhov tsim nyog ntawm HPMC yog 0.10% ~ 0.20%. Kev soj ntsuam ntawm nws cov dej tuav mechanism: Cellulose ether yog cov dej-soluble organic polymer, uas muab faib ua ionic thiab non-ionic. HPMC yog ib qho non-ionic cellulose ether nrog pawg hydrophilic, pawg hydroxyl (-OH) thiab ether daim ntawv cog lus (-0-1) hauv nws cov qauv qauv. Thaum yaj hauv dej, cov pa oxygen atoms ntawm pawg hydroxyl thiab ether daim ntawv cog lus thiab dej Molecules koom ua ke los tsim cov ntawv cog lus hydrogen, uas ua rau dej poob nws cov dej, thiab dej dawb tsis pub dawb, yog li ua tiav cov txiaj ntsig ntawm dej tuav thiab thickening.

2.4 Compressive zog

Los ntawm kev sib raug zoo ntawm lub zog compressive thiab tus nqi ntawm HPMC, nws tuaj yeem pom tau tias nrog qhov nce ntawm HPMC, lub zog compressive ntawm 7d thiab 28d tau pom qhov kev poob qis, uas feem ntau yog vim muaj ntau tus neeg siv. ntawm huab cua npuas los ntawm HPMC, uas zoo heev ua rau lub porosity ntawm lub mortar. nce, ua rau txo qis zog. Thaum cov ntsiab lus yog 0.05%, 7d compressive zog poob qis heev, lub zog poob los ntawm 21.0%, thiab 28d compressive zog poob los ntawm 26.6%. Nws tuaj yeem pom los ntawm qhov nkhaus uas qhov cuam tshuam ntawm HPMC ntawm lub zog compressive yog qhov pom tseeb heev. Thaum cov koob tshuaj tsawg heev, nws yuav txo qis heev. Yog li ntawd, hauv kev siv tswv yim, nws cov koob tshuaj yuav tsum tau tswj thiab siv ua ke nrog defoamer. Tshawb nrhiav qhov laj thawj, Guan Xuemao et al. ntseeg hais tias ua ntej, thaum cellulose ether ntxiv rau hauv mortar, qhov hloov tau yooj yim polymer nyob rau hauv mortar pores yog nce, thiab cov hloov tau yooj yim polymers thiab pores tsis tuaj yeem muab kev txhawb nqa nruj thaum qhov kev sim thaiv yog compressed. Lub composite matrix kuj tsis muaj zog, yog li txo cov compressive zog ntawm lub mortar; Qhov thib ob, vim yog cov dej tuav cov nyhuv ntawm cellulose ether, tom qab lub mortar test block tau tsim, feem ntau ntawm cov dej tseem nyob hauv mortar, thiab qhov tseeb dej-cement piv yog qis dua qhov uas tsis muaj qhov loj dua, yog li lub zog compressive. ntawm mortar yuav raug txo kom tsawg.

2.5 Correlation ntawm compressive zog thiab ntub ntom ntom

Nws tuaj yeem pom los ntawm kev sib raug zoo nkhaus ntawm lub zog compressive thiab ntub ntom ntom uas tom qab linear haum ntawm tag nrho cov ntsiab lus hauv daim duab, cov ntsiab lus sib txuas tau zoo faib rau ob sab ntawm cov kab haum, thiab muaj kev sib raug zoo ntawm ntub ntom ntom thiab compressive. Lub zog muaj zog, thiab qhov ntom ntom ntub yog qhov yooj yim thiab yooj yim los ntsuas, yog li lub zog compressive ntawm mortar 28d tuaj yeem suav los ntawm kev tsim kab sib npaug. Txoj kab sib npaug sib npaug yog qhia hauv mis (1), R²= 0.9704. Y = 0.0195X-27.3 (1), qhov twg, y yog 28d compressive zog ntawm mortar, MPa; X yog qhov ntub dej ntom ntom, kg m-3.

3. Cov lus xaus

HPMC tuaj yeem txhim kho cov dej tuav cov nyhuv ntawm ya tshauv mortar thiab ncua lub sijhawm ua haujlwm ntawm cov tshuaj khib nyiab. Nyob rau tib lub sijhawm, vim qhov nce ntawm cov porosity ntawm lub zog ntawm lub ntig, nws cov tuab thiab compressive zog yuav ua rau raug xaiv hauv daim ntawv thov. Lub 28d compressive zog ntawm mortar muaj kev sib raug zoo nrog cov ntub ntom ntom, thiab 28d compressive lub zog tuaj yeem raug xam los ntawm kev ntsuas qhov ntub dej, uas muaj qhov tseem ceeb siv tus nqi rau kev tswj xyuas zoo ntawm mortar thaum tsim kho.