Dab tsi yog cov teeb meem tshwm sim ntawm polycarboxylic acid admixtures hauv kev siv engineering?
Jul 29, 2024
Polycarboxylate superplasticizers (PCEs) yog suav tias yog cov khoom siv ua haujlwm siab. Lawv cia siab tias yuav muaj kev nyab xeeb dua, yooj yim dua, ua haujlwm tau zoo, thiab yoog tau piv rau cov tshuaj naphthalene-raws li cov tshuaj sib xyaw. Txawm li cas los xij, hauv kev siv tswv yim, ntau yam teeb meem tshwm sim, ntau yam uas tsis tau pom dua nrog naphthalene-based admixtures. Piv txwv li, qee zaum cov pob zeb ua pov thawj zoo slump, flowability, thiab dej tuav thaum tawm hauv lub Hoobkas, tab sis thaum lub sij hawm nws tuaj txog ntawm qhov chaw tsim kho, nws qhia tau hais tias tus cwj pwm phem. Cov pob zeb yuav qhuav heev thiab tsis tuaj yeem ua haujlwm, ua kom tshem tawm thiab siv tsis tau, lossis nws tuaj yeem cais thiab los ntshav hnyav, ua rau lub twj tso kua mis txhaws.
Yog vim li cas rau cov teeb meem no yog ob yam:
Kev tsis sib haum xeeb ntawm PCEs:Qhov zoo ntawm PCEs tuaj yeem tsis ruaj khov vim qhov sib txawv ntawm cov khoom siv raw siv hauv txhua pawg, ua rau kev ua haujlwm tsis sib xws.
Kev sib tw thiab kev tsim khoom:Cov kws tshaj lij thiab cov txheej txheem tsim khoom ntawm PCE cov tuam txhab tseem ua lub luag haujlwm tseem ceeb hauv kev tswj hwm PCEs zoo.
High Sensitivity thiab Poor Adaptability ntawm PCEs:PCEs yog cov rhiab heev thiab tsis tshua hloov tau piv rau naphthalene-based admixtures. Cov kev hloov me me hauv qhov muaj pes tsawg leeg thiab keeb kwm ntawm cov khoom siv raw tuaj yeem cuam tshuam rau kev ua tau zoo. Qhov kev nkag siab zoo no yuav tsum muaj kev nkag siab zoo thiab maj mam hloov kho kom ua tiav cov txiaj ntsig ntawm PCEs.
Tej yam cuam tshuam rau Adaptability ntawm PCEs
Cement
Lub adaptability ntawm PCEs yog cuam tshuam los ntawm cov tshuaj muaj pes tsawg leeg ntawm cov cement, hom gypsum, sib tsoo pab, tus nqi ntawm reactive thiab inert admixtures, cov ntsiab lus alkali, fineness, thiab kub ntawm cov cement. Cement yog cov khoom lag luam hauv cheeb tsam, thiab kev hloov pauv hauv cov ntxhia hauv cov khoom siv raw siv hauv cov cheeb tsam sib txawv tuaj yeem ua rau muaj kev hloov pauv loj hauv kev ua vaj tse. Hom gypsum, ntau cov ntsiab lus alkali, suav nrog kev sib tsoo, kev ua kom zoo, thiab cov cement kub tuaj yeem cuam tshuam rau kev hloov pauv ntawm PCEs, ua rau muaj kev hloov pauv hauv kev khaws cia, ntws tawm, sib kis, thiab cohesion. Yog li ntawd, nws raug nquahu kom tsis txhob muaj kev hloov pauv ntau zaus hauv cov cement thiab xaiv cov cement zoo, ruaj khov.
Coarse thiab Fine Aggregates (Sand and Gravel)
Lub hauv paus tseem ceeb cuam tshuam rau kev hloov pauv ntawm PCEs yog cov av nkos hauv cov khoom sib sau. Nce av nkos ntsiab lus txo cov rheological zog ntawm pob zeb. Tsis tas li ntawd, hom av nplaum thiab pob zeb hmoov hauv cov khoom sib xyaw kuj tseem cuam tshuam rau kev hloov pauv ntawm PCEs. Cov av nkos siab txo cov dej txo tus nqi ntawm PCEs. Tsis zoo li naphthalene-raws li admixtures, qhov uas ua rau cov khoom siv ntxiv tuaj yeem daws cov teeb meem nrog cov av nkos siab, PCEs tsis teb qhov kwv yees kom nce ntxiv. Qee lub sij hawm, pob zeb pib los ntshav ua ntej ua tiav qhov xav tau flowability, ua rau nws nyuaj rau kev tswj cov tshuaj sib xyaw. Txoj hauv kev zoo tshaj plaws yog siv cov xuab zeb zoo thiab gravel nrog cov av nkos tsawg.
Admixtures (Mineral Powder, Fly Ash)
Kev hloov pauv ntawm PCEs feem ntau cuam tshuam los ntawm qhov poob ntawm qhov hluav taws xob (LOI) thiab qhov zoo ntawm cov khoom sib xyaw. High LOI nce qhov nqus ntawm cov khoom sib xyaw, xav tau ntau dua ntawm PCEs thiab ua rau poob sai sai. Xaiv qhov zoo ntawm Chav Kawm I lossis Chav Kawm II ya tshauv tuaj yeem ua tiav cov dej ntws zoo dua.
Los ntawm kev nkag siab thiab hais txog cov xwm txheej no, kev siv tau zoo ntawm polycarboxylate superplasticizers hauv pob zeb tuaj yeem txhim kho, ua kom muaj kev ua tau zoo dua thiab kev ntseeg siab hauv ntau yam kev siv.
