1) Kev txhim kho lub zog ntawm cov cement slurry thiab mortar yog ib qho ntawm cov cim qhia txog kev ua tau zoo ntawm cov pob zeb ua vaj tse. Ib qho ntawm cov hom phiaj tseem ceeb ntawm kev ntxiv metakaolin yog los txhim kho lub zog ntawm cov cement mortar thiab concrete.

Poon et al, Nws lub zog ntawm 28d thiab 90d yog sib npaug rau cov metakaolin cement, tab sis nws lub zog thaum ntxov qis dua li cov cement benchmark. Kev tshuaj xyuas qhia tias qhov no yuav muaj feem cuam tshuam nrog kev sib sau ua ke ntawm cov hmoov silicon siv thiab kev sib xyaw tsis txaus hauv cov cement slurry.

(2) Li Keliang et al. (2005) tau kawm txog cov teebmeem ntawm qhov kub thiab txias ntawm calcination, lub sijhawm calcination, thiab SiO2 thiab A12O3 cov ntsiab lus hauv kaolin ntawm kev ua haujlwm ntawm metakaolin los txhim kho lub zog ntawm cov cement concrete. Cov pob zeb muaj zog thiab cov av polymers tau npaj siv metakaolin. Cov txiaj ntsig qhia tau tias thaum cov ntsiab lus ntawm metakaolin yog 15% thiab qhov sib piv ntawm dej cement yog 0.4, lub zog compressive ntawm 28 hnub yog 71.9 MPa. Thaum cov ntsiab lus ntawm metakaolin yog 10% thiab qhov sib piv ntawm dej cement yog 0.375, lub zog compressive ntawm 28 hnub yog 73.9 MPa. Ntxiv mus, thaum cov ntsiab lus ntawm metakaolin yog 10%, nws cov ntsuas kev ua haujlwm ncav cuag 114, uas yog 11.8% siab dua li tib yam ntawm cov hmoov silicon. Yog li ntawd, nws ntseeg tias metakaolin tuaj yeem siv los npaj cov pob zeb muaj zog siab.

Kev kawm txog kev sib raug zoo ntawm kev nyuaj siab thiab kev ntxhov siab ntawm cov pob zeb ua vaj tse nrog 0, 0.5%, 10%, thiab 15% metakaolin cov ntsiab lus tau raug kawm. Nws tau pom tias nrog kev nce ntawm cov ntsiab lus metakaolin, qhov siab tshaj plaws ntawm lub zog axial tensile ntawm cov pob zeb ua vaj tse tau nce ntxiv ntau heev, thiab cov tensile elastic modulus tseem tsis tau hloov pauv. Txawm li cas los xij, lub zog compressive ntawm cov pob zeb ua vaj tse tau nce ntxiv ntau heev, thaum qhov piv ntawm lub zog compressive tau txo qis. Lub zog tensile thiab lub zog compressive ntawm cov pob zeb ua vaj tse nrog 15% kaolin cov ntsiab lus yog 128% thiab 184% ntawm cov pob zeb siv, raws li.
Thaum kawm txog qhov ua kom muaj zog ntawm cov hmoov ultrafine ntawm metakaolin rau ntawm cov pob zeb ua vaj tse, nws pom tias nyob rau hauv tib lub fluidity, lub zog compressive thiab flexural zog ntawm mortar uas muaj 10% metakaolin nce ntxiv los ntawm 6% mus rau 8% tom qab 28 hnub. Kev loj hlob ntawm lub zog thaum ntxov ntawm cov pob zeb sib xyaw nrog metakaolin tau nrawm dua li ntawm cov pob zeb txheem. Piv nrog rau cov pob zeb txheem, cov pob zeb uas muaj 15% metakaolin muaj 84% nce hauv 3D axial compressive zog thiab 80% nce hauv 28d axial compressive zog, thaum lub static elastic modulus muaj 9% nce hauv 3D thiab 8% nce hauv 28d.

Kev kawm txog kev cuam tshuam ntawm kev sib xyaw ntawm cov av metakaolin thiab slag rau lub zog thiab kev ruaj khov ntawm cov pob zeb ua vaj tse. Cov txiaj ntsig qhia tau tias kev ntxiv metakaolin rau hauv cov pob zeb ua vaj tse ua rau lub zog thiab kev ruaj khov ntawm cov pob zeb ua vaj tse zoo dua, thiab qhov sib piv zoo tshaj plaws ntawm slag rau cement yog nyob ib puag ncig 3: 7, ua rau lub zog pob zeb zoo tagnrho. Qhov sib txawv ntawm cov pob zeb ua vaj tse sib xyaw yog siab dua me ntsis ntawm cov pob zeb ua vaj tse ib leeg vim yog cov tshauv volcanic ntawm metakaolin. Nws lub zog tensile sib cais yog siab dua li ntawm cov pob zeb ua vaj tse benchmark.

Kev ua haujlwm tau zoo, lub zog compressive, thiab lub zog durability ntawm cov pob zeb ua vaj tse tau kawm los ntawm kev siv metakaolin, fly ash, thiab slag ua cov khoom hloov rau cement, thiab sib tov metakaolin nrog fly ash thiab slag sib cais los npaj cov pob zeb ua vaj tse. Cov txiaj ntsig qhia tau tias thaum metakaolin hloov 5% txog 25% cement hauv qhov sib npaug, lub zog compressive ntawm cov pob zeb ua vaj tse txhua lub hnub nyoog tau zoo dua; Thaum metakaolin siv los hloov cement los ntawm 20% hauv qhov sib npaug, lub zog compressive ntawm txhua lub hnub nyoog yog qhov zoo tagnrho, thiab nws lub zog ntawm 3d, 7d, thiab 28d yog 26.0%, 14.3%, thiab 8.9% siab dua li ntawm cov pob zeb ua vaj tse tsis muaj metakaolin ntxiv, raws li. Qhov no qhia tau hais tias rau Hom II Portland cement, ntxiv metakaolin tuaj yeem txhim kho lub zog ntawm cov pob zeb ua vaj tse uas tau npaj tseg.

Siv cov hlau slag, metakaolin, thiab lwm yam khoom siv ua cov khoom siv tseem ceeb los npaj cov cement geopolymer es tsis txhob siv cov cement Portland ib txwm muaj, txhawm rau ua tiav lub hom phiaj ntawm kev txuag hluav taws xob, txo kev siv, thiab hloov cov khib nyiab mus ua khoom muaj nqis. Cov txiaj ntsig qhia tau tias thaum cov ntsiab lus ntawm hlau thiab cov tshauv ya yog ob qho tib si 20%, lub zog ntawm lub thaiv sim ntawm 28 hnub ncav cuag siab heev (95.5MPa). Raws li qhov ntau ntawm cov hlau slag ntxiv nce ntxiv, nws kuj tuaj yeem ua lub luag haujlwm hauv kev txo qhov shrinkage ntawm geopolymer cement.

Siv txoj kev siv tshuab "Portland cement + cov khoom siv sib xyaw ua ke + cov neeg ua haujlwm txo dej zoo", cov thev naus laus zis magnetized dej, thiab cov txheej txheem npaj ib txwm muaj, kev sim tau ua rau kev npaj cov pob zeb slag pob zeb uas muaj cov pa roj carbon tsawg thiab cov khoom siv siab heev siv cov khoom siv raw xws li pob zeb thiab slag los ntawm ntau qhov chaw hauv zos. Cov txiaj ntsig qhia tau tias qhov ntau npaum li cas ntawm metakaolin yog 10%. Qhov sib piv ntawm qhov hnyav rau lub zog ntawm cov cement rau ib chav tsev ntawm cov pob zeb slag pob zeb uas muaj zog heev yog li 4.17 npaug ntawm cov pob zeb ib txwm muaj, 2.49 npaug ntawm cov pob zeb muaj zog heev (HSC), thiab 2.02 npaug ntawm cov hmoov pob zeb reactive (RPC). Yog li ntawd, cov pob zeb slag pob zeb uas muaj zog heev uas npaj nrog cov cement tsawg yog qhov kev coj ua ntawm kev txhim kho pob zeb hauv lub sijhawm kev lag luam uas muaj cov pa roj carbon tsawg.

(3) Tom qab ntxiv kaolin uas tiv taus te rau hauv cov pob zeb ua vaj tse, qhov loj ntawm cov pob zeb ua vaj tse raug txo qis heev, txhim kho lub voj voog khov-thaw ntawm cov pob zeb ua vaj tse. Nyob rau hauv qee qhov kev voj voog khov-thaw, qhov elastic modulus ntawm cov qauv pob zeb ua vaj tse nrog 15% kaolin cov ntsiab lus ntawm 28 hnub ntawm hnub nyoog yog siab dua li ntawm cov pob zeb siv piv txwv ntawm 28 hnub ntawm hnub nyoog. Kev siv cov metakaolin thiab lwm yam hmoov av ultrafine hauv cov pob zeb ua vaj tse kuj tseem tuaj yeem txhim kho lub zog ntawm cov pob zeb ua vaj tse.