Dab tsi yog qhov kev tsim txom ntawm overmixing polycarboxylate superplasticizers

Polycarboxylate superplasticizers yog dav siv nyob rau hauv niaj hnub pob zeb tsim thiab ua si lub luag haujlwm tseem ceeb hauv kev txhim kho cov pob zeb ua. Txawm li cas los xij, ntau dhau koob ntawm polycarboxylate superplasticizers tau ua rau ntau yam kev puas tsuaj ntawm cov pob zeb ua tau zoo. Daim ntawv no muab kev cuam tshuam zoo ntawm cov kev cuam tshuam tsis zoo ntawm polycarboxylate superarsticy, cov khoom siv txhua yam, thiab kav ntev. Los ntawm kev tshawb nrhiav rooj plaub, cov teeb meem no tau tshuaj xyuas, thiab cov lus qhia txog kev daws teeb meem ntawm polycarboxylate superplasticizers hauv pob zeb ntau lawm thiab kev tsim kho.

1. Pib

Nrog rau kev txhim kho sai sai ntawm kev tsim kho kev tsim kho, kev ua yeeb yam uas yuav tsum muaj rau cov pob zeb ua kom nce ntxiv. Raws li ib qho kev ua haujlwm zoo admixture, polycarboxylate superplasticizers super los vim lawv cov dej txo qis, poob qis rau ntawm kev cuam tshuam rau durability. Txawm li cas los xij, hauv kev tsim khoom tiag tiag thiab kev tsim kho, ntau dhau los ntawm polycarboxylate superplasticizers feem ntau tshwm sim tsis ua tiav, cov neeg teb xov tooj yuam kev, thiab kev ntsuas tsis txaus ntawm kev hloov ua vaj tse. Xws li tshwm sim pose muaj kev pheej hmoo loj rau kev nyab xeeb thiab tsim kev nyab xeeb. Yog li ntawd, kawm qhov cuam tshuam tsis zoo ntawm polycarboxylate superplasticizer dosing thiab txhim kho cov kev daws teeb meem yog qhov tseem ceeb ntawm kev tseem ceeb.

2. Kev ua haujlwm thiab ua haujlwm mechanism ntawm polycarboxylate superplasticizers

2.1 Lub Luag Haujlwm Loj

Polycarboxylate superplasticizers feem ntau pab dej-txo cov dej ntws-txo qis, tuav tseg, thiab rov ua haujlwm. Qhov tsim nyog ntxiv ntawm polycarboxylate superplasticizers rau cov pob zeb ua tau zoo txo ​​tau cov kab ke dej kom zoo, ua kom muaj zog dua, thiab kev txhim kho kev hloov pauv. Tsis tas li ntawd, cov lus Askiv no txo ​​qis qis qis, ua kom muaj kev tswj hwm kom tswj cov haujlwm tau ua haujlwm zoo nyob rau ncua sijhawm. Tsis tas li ntawd, lawv cov txiaj ntsig rov qab tiv thaiv kev npaj ntxov thaum lub sijhawm thauj mus los thiab tso rau, muab sijhawm rau kev siv sijhawm txaus.

2.2 Kev Ua Haujlwm

Polycarboxylate superplasticizers muaj nuj nqi los ntawm cov pab pawg accium thiab sulfonic sids nrog rau cov khoom noj khoom haus cov khoom tsis zoo adsorption. Lub tshuab hluav taws xob rov qab nruab nrab ntawm cov kev hloov pauv sib thooj sib tsoo tsoo agglomerates, dispersing cov movent cov cai thiab tso tawm cov nyhuv dej-txo cov nyhuv dej. Tsis tas li ntawd, txoj sia nyob ntev ntawm Superplasticizer Molecules tsim cov khoom sib txawv, txuas ntxiv tiv thaiv kev ua plees ua ke thiab tswj kom poob qis.

3. Cov teeb meem tsis zoo ntawm polycarboxylate superplasticizer siv cov khoom siv pob zeb

3.1 cuam tshuam rau kev ua haujlwm

3.1.1 kev tshaj tawm ntau dhau, cais tawm, thiab los ntshav

Thaum polycarboxylate superplasticizers tau overdosed, lawv cov nyhuv uas txo qis zuj zus lawm, ua rau muaj kev sib xyaw ua kom sib xyaw. Kev haus dej dawb dhau los, nyob rau hauv cov kev cuam tshuam ntawm lub ntiajteb txawj nqus, cais tawm ntawm cov Maas muab tshuaj txhuam, ua rau muaj kev sib cais. Coarse aggregates dab dej thaum Maas Paste floats, ua rau muaj kev faib khoom tsis sib xws ntawm cov khoom sib xyaw ua ke, nyuaj zuag qhia tag nrho thiab kev tsim kho. Tsis tas li ntawd, los ntshav ua kom muaj zog, ua cov yeeb yaj kiab dej ntawm cov pob zeb ua kom muaj zog thiab nce siab sab hauv porosity, txo kev tiv thaiv sab hauv.

Piv txwv li, hauv lub hauv paus pouring ntawm cov phiaj xwm kev lag luam siab, ntau dhau ntawm polycarboxylate superRationgastizer tau coj mus rau ntawm qhov chaw tsim kho. Hauv qee thaj chaw, coarse aggregates tau nce thaum cov cement muab tso tawm, xav tau kev ua noj ua haus, ncua sij hawm, thiab cov nqi ntxiv.

3.1.2 Lub sijhawm tsis muaj sijhawm

Lub sij hawm retarding ntawm polycarboxylate superplastic qhob teeb tsa lub sijhawm thaum dhau los, tawm hauv lub xeev tsis raug cai thiab cuam tshuam kev tsim kho cov dej num. Nyob rau hauv lub sij hawm-retor projects, xws li loj qhob muab ncuav, teeb tsa lub caij nyoog tuaj yeem ua rau cov pob txha txias, txo cov qauv kev ncaj ncees thiab lub zog. Hloov siab, qee kis, ntau polycarboxylate superplasticizylate superarstance yog qhov tsis txaus ntseeg vim muaj kev lom zem rau cov cement, ua rau Flashion. Qhov no ua rau muaj cov pob zeb ua tsis tau zoo, cuam tshuam rau kev tsim kho zoo.

Piv txwv li, hauv tus choj Pier kev tsim kho, ntau polycarboxylate superplasticizy txuas ntxiv lub storar tying thiab formwork installation thiab cuam tshuam rau kev nce qib.

3.2 cuam tshuam rau ntawm cov tshuab khoom siv

3.2.1 qeeb kev txhim kho thaum ntxov

Overdoing Polycarboxylate superplasticizers inibits thaum ntxov kev coasent ntawm cov cement, qeeb ntxov ntxov. Lub zog thaum ntxov muaj zog thaum ntxov yuav ua rau deformation thiab tawg hauv qab qhov hnyav, kev siv kev tsim kho, lossis kev siv ib puag ncig. Hauv cov qauv yuav tsum tau tshem tawm cov txheej txheem thaum ntxov, xws li cov txheej txheem ntsug hauv kev txhim kho cov sijhawm tsim kho thiab kev cuam tshuam zoo qauv kev nyab xeeb.

Piv txwv li, nyob rau hauv lub ntsej muag precast ntau lawm cog, ntau dhau ntawm polycarboxylate superplasticizer tshwm sim hauv kev cuam tshuam thiab teeb tsa cov caij nyoog tsim khoom.

3.2.2 Txo lub zog ntev ntev

Ntau polycarboxylate superplasticizer tuaj yeem tsis zoo cuam tshuam rau lub zog ntev los yog hloov microstructure ntawm kev ua vaj tse. Nws ua rau thaj chaw hloov pauv ntawm cov cement muab tshuaj thiab aggregates, nce porosity thiab txo cov qhob zog. Nyob rau hauv kev thauj khoom lossis kev mob hnyav, cov teeb meem no ib puag ncig, cov kev tsis muaj zog no txo ​​qis thiab kev pabcuam lub neej ruaj khov. Kev tshawb fawb qhia tau tias Overdosing Polycarboxylate SuperPlasticizer los ntawm 10% tuaj yeem txo {{hnub ua qhob zog los ntawm {}}%.

Piv txwv li, nyob rau hauv lub phiaj xwm kev ua si khaub ncaws loj loj, ntau dhau ntawm Polycarboxylate superplasticizer tau tshwm sim hauv qab kev tsim kev sib tsoo, kev nyab xeeb ntawm lub zog.

3.3 kev cuam tshuam rau durability

3.3.1 Txo cov permeabentility tiv taus

Pob zeb ua ke ua haujlwm tsis kam yog ib qho tseem ceeb Durability. Tshaj tawm polycarboxylate superplastictizer ua rau kab mob kab mob thiab los ntshav, tsim cov khoom sib txuam ua cov dej thiab cov khoom phom sij. Qhov kev hais no cov qauv zoo xws li cov chaw hauv av thiab cov qauv hauv cov qauv hauv av, ua kom muaj kev pheej hmoo ntawm dej infiltration thiab tshuaj lom neeg.

Piv txwv li, ib qho chaw nres tsheb ua si hauv av tshiab tau paub txog cov dej ntws thoob plaws tom qab ua tiav. Kev soj ntsuam qhia tias ntau polycarboxylate superplasticizer tau txo qis cov kab nrib pleb

3.3.2 Sau kom tiav khov-thaw tsis kam

Hauv cov huab cua txias txias, khov-thaw kev tiv thaiv yog qhov tseem ceeb rau kev siv lub sijhawm ntev. Ntau polycarboxylate superplasticizer nce cov huab cua huab cua ua kom muaj cov ntsiab lus huab cua ua ke, ua rau muaj mob khov kho, txo qhov tsis ntev. Ib qho ntxiv, kev cais tawm-induced inomogeneity worsen khov-thaws puas tsuaj, ua rau nto spalling thiab tawg.

Piv txwv li, tus choj qhov project nyob rau hauv ib cheeb tsam sab qaum teb qhia qhov chaw hnyav heev tom qab ib lub caij ntuj no. Kev tsom xam tau qhia tias cov polycarboxylate superplasticizer tau txo kom khov-thaws tiv thaiv, ua rau muaj kev puas tsuaj huab cua kev puas tsuaj.

3.3.3 tsis muaj carbonation tsis muaj zog tiv

Kev ua pob ua pob ua pob ua haujlwm tshwm sim thaum cov calcium hydroxide nyob rau hauv cov cement carbonate thiab txo alkality. Ntau dua polycarboxylate superplasticizer tuaj yeem hloov cov ntsiab lus hydroxide cov ntsiab lus thaum nce porosity, accelating carbonation. Carbonation tsis muaj zog tiv thaiv cov kev tiv thaiv passivation txheej ntawm kev txhawb nqa hlau, ua rau kev teeb meem corrosion thiab kev ua yeeb yam.

Piv txwv li, lub tsev tsim cov tsev ua haujlwm pom tau tias muaj roj ntau ntxiv tom qab ob peb xyoos, ua rau rebar corrosion thiab tawg, ua rau muaj kev ncaj ncees. Ntau polycarboxylate superplasticizer tau pom tias lub hauv paus ua rau cov carbonation sai.

Vim muaj kev sib txawv hauv cov kev cai ua kom xis nyob thiab kev txiav txim siab sib xyaw, kev txiav txim siab rau cov lus pom zoo ib yam nkaus Siv Caas muab cov kev ntsuam xyuas Flowility uas yooj yim, thiab txhim kho cov nqi ua kom zoo, txo cov nqi, thiab ua tiav cov txiaj ntsig zoo tshaj plaws.