Dab tsi yog qhov kev ua haujlwm ntawm cov pob zeb ua dej txo tus neeg sawv cev

1.Lub luag hauj lwm ntawm cov khoom siv dej txo qis

Concrete water reducers yog additives uas yuav txo tau qhov sib tov dej uas yuav tsum tau thaum tuav tib slump. Lawv raug cais raws li lawv cov nqi txo cov dej mus rau hauv qhov zoo tib yam, kev ua haujlwm siab, thiab cov dej ua haujlwm siab.

Lub luag haujlwm tseem ceeb ntawm cov dej reducers tuaj yeem muab faib ua plaub hom: ua kom muaj dej ntau ntxiv, ua kom cov pob zeb ua kom muaj zog, txuag cov cement, thiab txhim kho cov pob zeb ua kom ntev.

• 01 Ntxiv Fluidity

Nrog rau qhov ntim dej tas li thiab dej-cement piv, qhov ntws ntawm cov pob zeb tuaj yeem nce los ntawm 100 mus rau 200 hli yam tsis muaj kev cuam tshuam nws lub zog.

• 02 Txhim kho pob zeb muaj zog

Nyob rau hauv tej yam kev mob uas fluidity thiab cement cov ntsiab lus tseem tsis hloov pauv, cov dej sib tov tuaj yeem txo los ntawm 10% mus rau 40%, ua rau qis dej-cement piv thiab ua rau cov pob zeb ua kom muaj zog.

• 03 Txuag Cement

Los ntawm kev tswj cov dej ntws thiab cov pob zeb ua kom muaj zog, nws tuaj yeem txo cov dej sib tov thiab cov cement siv.

• 04 Txhim kho pob zeb ua kom ntev

Kev sib koom ua ke ntawm cov dej reducers tuaj yeem txhim kho qhov impermeability thiab khov-thaw ua haujlwm ntawm cov pob zeb, nrog rau kev txhim kho kev sib raug zoo ntawm steel reinforcement thiab pob zeb.

2. Yuav ua li cas dej txo cov dej kom txo tau

Vim li cas cov dej reducers zoo txo ​​cov ntsiab lus dej? Peb yuav tsum pib nrog cov cement.

Thaum lub sij hawm sib tov, cov ntxhia hauv cov cement muaj cov khoom sib txawv nrog cov nqi sib txawv. Lub attraction ntawm qhov zoo thiab tsis zoo nqi ua rau tsim ib tug flocculated qauv nyob rau hauv lub pob zeb, uas tej zaum kuj tshwm sim vim lub thermal motion ntawm cement hais colliding thiab attracting ib leeg nyob rau hauv dej.

Cov qauv flocculated no encapsulates qee cov dej sib tov, txo cov dej dawb. Thaum ntxiv cov dej reducer, nws cov teebmeem tuaj yeem pom hauv plaub yam hauv qab no: lubrication, dispersion, steric hindrance, thiab graft copolymer qeeb-tso cuam tshuam.

• 01 Lubrication

Cov dej reducers muaj cov pab pawg polar hydrophilic, uas tsim ib qho kev daws teeb meem ruaj khov rau ntawm cov cement hais. Cov yeeb yaj kiab dej no muaj cov khoom siv lubrication zoo, txo cov zawv zawg tiv thaiv ntawm cov cement hais, ntxiv dag zog rau cov dej ntws ntawm cov pob zeb.

• 02 Kev tawg

Thaum cov cement sib tov nrog dej, hydration ua rau cov cement hais los tsim ib txheej txheej ob txheej, tsim ib zaj duab xis dej daws. Cov khoom muaj cov nqi sib txawv, ua rau muaj kev sib txuam ua ke uas tsim cov qauv flocculated, ua rau 10% mus rau 30% ntawm cov dej sib tov kom tau ntim thiab tsis muaj rau kev khiav dawb thiab lubrication, yog li cuam tshuam cov flowability ntawm cov pob zeb sib tov.

Raws li qhov sib ntxiv ntawm cov dej reducer, cov molecules tuaj yeem taw qhia lawv tus kheej ntawm cov cement hais, ua rau lawv nqa tib tus nqi (feem ntau tsis zoo). Qhov no ua rau electrostatic repulsion, txhawb kev dispersion ntawm cov cement hais, rhuav tshem cov qauv flocculated, thiab tso cov dej encapsulated los koom rau hauv kev khiav, yog li ua kom cov flowability ntawm cov pob zeb sib tov.

• 03 Steric Hindrance

Cov qauv ntawm cov dej reducers muaj xws li hydrophilic sab chains uas txuas mus rau hauv cov kev daws teeb meem, tsim ib txheej tuab hydrophilic adsorption txheej rau saum npoo ntawm cov cement hais. Raws li cov cement hais mus rau ib leeg, txheej txheej no pib sib tshooj, tsim steric hindrance. Qhov sib tshooj ntau dua, qhov ntau dua qhov steric hindrance, uas inhibits cohesive rog ntawm cov cement hais, kom ntseeg tau zoo slump tuav hauv cov pob zeb.

04 Graft Copolymer Slow-Release Effect

Thaum lub sij hawm npaj ntawm polycarboxylic acid dej reducers, ib co sab chains yog grafted mus rau lub molecules. Cov saw hlau no tsis tsuas yog muab kev cuam tshuam steric tab sis kuj tuaj yeem maj mam cleaved nyob rau hauv high-alkalinity ib puag ncig ntawm cement hydration, tso dispersing agents xws li polycarboxylic acid. Qhov no txhim khu cov dispersion ntawm cement hais thiab tswj slump poob.