Kev saib xyuas yuav tsum tau them rau kev sib xyaw ua ke

Tam sim no, cov txheej txheem tsim cov pob zeb sib xyaw tsuas yog siv cov txheej txheem tsim khoom yooj yim, lossis nws tsuas yog tsom rau kev txhim kho kev ua tau zoo ntawm cov pob zeb yam tsis xav txog qhov cuam tshuam ntawm qee yam khoom thiab lawv qhov ntau npaum li cas ntawm cov pob zeb muaj zog thiab kav ntev.

Hauv qab no yog ib qho kev txheeb xyuas luv luv ntawm cov teeb meem yuav tsum paub txog thaum lub sij hawm tsim cov txheej txheem sib xyaw, qhov ua rau cov teeb meem no, thiab lawv cov kev phom sij.

1. Kev tswj nruj ntawm cov tshuaj chloride Ion noj

Triethanolamine, sodium nitrite, thiab lwm yam khoom siv feem ntau yog siv rau lub caij ntuj no los tiv thaiv khov thiab cov khoom siv tshuaj tiv thaiv kab mob. Thaum cov ntsev ua ke nrog triethanolamine los yog sodium nitrite, lawv pom cov teebmeem tseem ceeb thaum ntxov thiab txhim kho kev ua haujlwm tiv thaiv kab mob. Thaum lub caij ntuj no admixture formulation txheej txheem, ntau manufacturers ntxiv ntsev, tab sis tus nqi txawv ho. Qhov txaus ntshai ntawm ntsev ntxiv yog pom tseeb. Qee cov tuam txhab ntseeg tias ntxiv cov ntsev me me tuaj yeem txhim kho cov khoom tiv thaiv kab mob thiab lub zog thaum ntxov yam tsis muaj ntau tshaj li lub teb chaws tus qauv ntawm 0.06% chloride ion cov ntsiab lus, thiab qhov no yog qhov tsim nyog. Xwb, ntxiv ntsev me ntsis rau cov pob zeb qis qis kuj xav tias tsis muaj mob.

Txawm li cas los xij, kev qhia txog cov tshuaj chloride ntsev rau hauv cov khoom sib xyaw tuaj yeem ua rau muaj kev puas tsuaj loj rau lub ntim ruaj khov thiab kav ntev ntawm cov pob zeb. Cov teebmeem tseem ceeb yog raws li nram no:

A. Chloride ions ua raws li corrosive agents infiltrate pob zeb thiab txo nws alkalinity, uas rhuav tshem cov passivation zaj duab xis nyob rau saum npoo ntawm steel reinforcement. Qhov no ua rau muaj qhov sib txawv loj ntawm cov hlau, ua rau cov tshuaj tiv thaiv electrochemical uas tsim cov anodes thiab cathodes.

B. Chloride ntsev, los ntawm kev rov ntub dej thiab crystallization hauv pob zeb, tsim cov khoom siv lead ua loj dua uas nthuav dav hauv ntim, ua rau tawg thiab txo cov pob zeb ua kom ntev.

C. Melting thiab aggregation feem ntau txhais tau hais tias hauv cov pob zeb uas muaj zog zoo tib yam, cov tshuaj chloride ntsev tsis tshaj {{0}}.5% yuav tsis ua rau xeb. Txawm li cas los xij, cov nyhuv ntawm sodium chloride rau txo qis qhov chaw khov ntawm cov tshuaj ua rau cov pob zeb khov los ntawm sab nraud nyob rau hauv. Raws li cov tshuaj unfreezing nce nyob rau hauv cov tshuaj chloride ion concentration, nws yuav ntau tshaj 0.5%, ua rau lub zos xeb. Hauv kev tsim khoom tiag tiag, txawm tias me me ntawm chloride ntsev tuaj yeem tsim muaj ntau dua hauv zos, ua rau corrosion. Tsis tas li ntawd, sodium chloride, tsis zoo li calcium chloride, tsis koom ua ke rau hauv cov khoom hydration 'molecular qauv tab sis tseem nyob hauv lub xeev dawb hauv qhov pores, absorbing noo noo thiab nce shrinkage nyob rau hauv hardened pob zeb, uas yog detrimental rau durability.

2. Kev cuam tshuam ntawm Alkali Cov ntsiab lus hauv Cement rau Admixtures

Cov ntsiab lus siab alkali hauv cov cement txo qhov ua tau zoo ntawm cov dej txo cov neeg ua haujlwm, txo lub sijhawm teem sijhawm, thiab ua kom muaj zog thaum ntxov. Ob qho tib si siab thiab qis alkali cov ntsiab lus hauv cov cement muaj qhov cuam tshuam tsis zoo rau kev sib raug zoo ntawm cov dej ua haujlwm siab nrog cov cement. Qhov no tuaj yeem yog vim muaj kev hloov pauv hauv kev solubility ntawm gypsum, cuam tshuam cov dej ntawm C3A (tricalcium aluminate). Cov ntsiab lus zoo soluble alkali yog nruab nrab ntawm 0.4% thiab 0.6% (sib npaug rau Na2O). Thaum kev sib raug zoo tsis zoo, ib feem ntawm cov khoom sib xyaw yuav tsum tau hloov nrog aminomethanesulfonic acid-raws li dej reducers (los yog polycarboxylate-raws li) los txhim kho cov khoom hloov pauv, thaum tseem ua kom tag nrho cov dej txo cov khoom.

3. Fineness thiab Freshness ntawm Cement

Qhov zoo dua cov cement, qhov loj dua qhov chaw tshwj xeeb, thiab qhov loj dua qhov chaw ntawm cov cement hais tias cov khoom sib xyaw yuav tsum ua rau. Cov cement tshiab muaj kev ua haujlwm siab dua thiab muaj zog adsorption ntawm cov khoom sib xyaw.

4. Hom thiab ntau npaum ntawm kev sib tsoo pab

Txhawm rau txhim kho cov khoom tsim tawm thiab cov cement zoo, cov cement nroj tsuag feem ntau ntxiv qee cov nyiaj sib tsoo thaum lub sijhawm sib tsoo. Txawm li cas los xij, hom thiab ntau npaum li cas ntawm cov kev pab no tuaj yeem muaj kev cuam tshuam loj rau kev sib xyaw ua ke. Piv txwv li, triethanolamine, feem ntau siv los ua kev sib tsoo, muaj cov nyhuv thaum ntxov ntawm cov tshuaj tsawg, tab sis ntawm qhov ntau npaum li cas saum toj no 0.04%, nws tuaj yeem ua rau muaj kev cuam tshuam loj heev. Cov nyhuv no tshwj xeeb tshaj yog thaum cov ntsev chloride los yog sodium nitrite muaj nyob rau lub caij ntuj no admixtures. Yog li ntawd, qhov cuam tshuam ntawm kev sib tsoo cov cuab yeej yuav tsum tau ua tib zoo txiav txim siab thaum xaiv los yog tsim cov khoom sib xyaw.

5. Kev cuam tshuam ntawm cov tshuaj ntxiv thiab lawv cov koob tshuaj

Lub peev xwm adsorption ntawm cov ntaub ntawv feem ntau ua raws li qhov kev txiav txim no: thee gangue> ya tshauv> slag. Cement nrog slag muaj kev sib raug zoo nrog cov khoom sib xyaw piv rau cov cement nrog coal gangue. Cov khoom siv hluav taws xob hluav taws xob feem ntau muaj thaj chaw loj dua, ua rau muaj kev nqus ntau dua thiab muaj kev cuam tshuam loj dua rau kev sib xyaw ua ke. Fly tshauv sib txawv heev nyob ntawm nws qib. Piv txwv li, chav kawm kuv ya tshauv muaj qhov zoo, lub ntsej muag lub ntsej muag zoo nkauj, cov ntsiab lus carbon tsawg, thiab tsis tshua muaj adsorption rau admixtures, uas yuav pab txhim kho cov pob zeb ua haujlwm. Txawm li cas los xij, ya tshauv nrog kev poob siab ntawm qhov hluav taws kub muaj cov ntsiab lus carbon ntau dua, thiab nws cov qauv silicon-oxygen tetrahedral muab nws lub peev xwm loj dua adsorption, yog li txo cov admixture compatibility. Ib yam li ntawd, qhov zoo ntawm cov hmoov ntxhia hmoov raws li ib qho ntxiv tuaj yeem cuam tshuam rau kev sib raug zoo nrog cov khoom sib xyaw.