Kev cuam tshuam ntawm cement thiab admixture compatibility ntawm pob zeb zoo

(1) Thaum cov ntsiab lus alkali hauv cov cement yog siab, qhov fluidity ntawm cov pob zeb yuav txo qis thiab qhov poob qis yuav nce ntxiv rau lub sijhawm, tshwj xeeb tshaj yog thaum siv cov dej txo qis nrog cov ntsiab lus sulfate tsawg. Cov nyhuv yog pom tseeb dua, thaum tus neeg saib xyuas dej-txo nrog cov ntsiab lus sulfate siab tuaj yeem txhim kho qhov xwm txheej no. Qhov no feem ntau yog vim cov calcium sulfate muaj nyob rau hauv cov dej-txo cov neeg ua haujlwm qis yog tsim thaum lub sij hawm synthesis thiab neutralization, thiab muaj cov dej solubility zoo heev. Yog li ntawd, thaum siv high-alkali xis mas, ntxiv ib tug npaum li cas ntawm sodium sulfate thiab hydroxyhydroxy acid ntsev retarders thaum compounding cov dej-txo tus neeg sawv cev yuav txhim kho lub fluidity thiab slump ntawm cov pob zeb.

(2) Thaum cov ntsiab lus alkali ntawm cov cement yog siab thiab pH tus nqi ntawm polycarboxylate dej-txo tus neeg saib xyuas qis, cov pob zeb yuav ua ntej tsim cov tshuaj tiv thaiv acid-base neutralization. Tsis tsuas yog qhov kub ntawm cov pob zeb yuav nce, tab sis nws tseem yuav ua kom cov dej ntawm cov cement. Lub fluidity thiab slump ntawm cov pob zeb yuav pom qhov poob loj heev hauv lub sijhawm luv luv. Yog li ntawd, thaum ntsib cov cement zoo sib xws, nws yog qhov zoo tshaj plaws tsis txhob siv cov citric acid retarders tab sis siv cov alkaline retarders es tsis txhob, xws li sodium hexametaphosphate, sodium polyphosphate, thiab lwm yam, uas muaj txiaj ntsig zoo dua.

(3) Thaum cov ntsiab lus alkali hauv cov cement yog tsawg, qhov fluidity ntawm pob zeb kuj tseem tsis zoo. Cov nyhuv ntawm qhov tsim nyog nce qhov ntau npaum li cas tsis pom tseeb, thiab cov pob zeb ua rau cov dej los ntshav. Qhov laj thawj tseem ceeb rau qhov tshwm sim no yog tias cov ntsiab lus sulfate ion hauv cov cement tsis txaus, uas txo cov nyhuv ntawm inhibiting hydration ntawm tricalcium aluminate hauv cov cement. Lub sijhawm no, ib qho nyiaj ntawm sulfates xws li sodium thiosulfate yuav tsum tau ntxiv thaum lub sij hawm sib xyaw kom ntxiv cov soluble alkali hauv cov cement.

(4) Thaum cov pob zeb oozes daj slurry, muaj ntau pinholes thiab npuas, nws tuaj yeem txiav txim siab tias leej niam cawv thiab cov cement nyuaj rau kev sib hloov. Lub sijhawm no, ethers, esters, aliphatic thiab lwm yam niam cawv tuaj yeem sib xyaw ua ke. Nyob rau tib lub sijhawm, nws yog ib qho tsim nyog yuav tsum txiav txim siab txo cov dej ntshiab uas txo cov niam cawv, ntxiv melamine thiab sodium hexametaphosphate thiab tom qab ntawd siv tus nqi tsim nyog ntawm defoaming tus neeg sawv cev. Tsis txhob siv cov khoom xws li thickeners. Kev siv cov thickeners yuav tsis ua npuas tawm, uas ua rau cov huab cua ntau dhau, txo cov pob zeb ntom ntom thiab pom tseeb lub zog txo. Yog tias tsim nyog, tannic acid lossis cov hmoov lead daj tuaj yeem ntxiv.

(5) Thaum lub foaming tivthaiv ntawm kev sib tsoo kev pab nyob rau hauv cov cement yog siab, cov pob zeb tseem ua rau yellowing thiab lub xeev yog tsis tshua muaj neeg pluag tom qab nyob twj ywm li 10 vib nas this. Qee lub sij hawm nws tau ua yuam kev ntseeg tias cov dej txo qis ntawm cov dej reducer siab dhau los yog huab cua ntau dhau yog ntxiv thaum sib xyaw. Qhov tseeb, nws yog ib qho teeb meem nrog kev sib tsoo cov cement. Thaum ntsib qhov teeb meem no, lub defoamer yuav tsum tau siv raws li tus nqi foaming ntawm kev sib tsoo, thiab tus neeg saib xyuas huab cua tsis tuaj yeem siv thaum sib xyaw.