Tsiku Lotumiza: 20 Jun, 2022

3. Limagwirira ntchito ya superplasticizers

Limagwirira wa madzi kuchepetsa wothandizira kusintha fluidity wa konkire osakaniza makamaka zikuphatikizapo dispersing tingati ndi lubricating kwenikweni. The madzi kuchepetsa wothandizila kwenikweni surfactant, mbali imodzi ya unyolo yaitali maselo mosavuta sungunuka m'madzi - gulu hydrophilic, ndi mapeto ena ndi insoluble m'madzi - hydrophobic gulu.

a. Kubalalitsidwa: Simenti ikasakanizidwa ndi madzi, chifukwa cha kukopa kwa maselo a tinthu tating'onoting'ono, matope a simenti amapanga mawonekedwe a flocculation, kotero kuti 10% mpaka 30% ya madzi osakanikirana amakutidwa mu tinthu tating'ono ta simenti ndipo sangathe kutenga nawo gawo mwaulere. kuyenda ndi mafuta. zotsatira, potero zimakhudza fluidity wa osakaniza konkire. Pamene madzi kuchepetsa wothandizila anawonjezera, chifukwa madzi kuchepetsa wothandizila mamolekyu akhoza directionally adsorbed padziko particles simenti, pamwamba pa simenti particles ali ndi mlandu womwewo (nthawi zambiri zoipa mlandu), kupanga electrostatic repulsion tingati amalimbikitsa kubalalitsidwa kwa particles simenti ndi chiwonongeko cha flocculation dongosolo. , kumasula gawo lokulungidwa la madzi ndi kutenga nawo mbali pakuyenda, potero kuonjezera madzi osakaniza a konkire.

b. Kupaka mafuta: gulu hydrophilic mu superplasticizer kwambiri polar, kotero adsorption filimu ya superplasticizer pamwamba pa simenti particles akhoza kupanga khola solvated filimu madzi ndi mamolekyu amadzi, ndi madzi filimu ali ndi mafuta abwino akhoza kuchepetsa kutsetsereka. kukana pakati pa simenti particles, potero kupititsa patsogolo fluidity wa konkire.

Zotsatira za chotsitsa madzi pa konkriti, ndi zina.

a. Ikani nthawi. Ma superplasticizers nthawi zambiri sakhala ochedwetsa, ndipo amatha kulimbikitsa kusungunuka ndi kuuma kwa simenti. The retarded superplasticizer ndi gulu la superplasticizer ndi retarder. Muzochitika zodziwika bwino, kuti muchedwetse hydration ya simenti ndikuchepetsa kutayika kwa kugwa, kuchuluka kwa retarder kumawonjezeredwa ku wochepetsera madzi.

b. Mafuta amafuta. Pakalipano, chochepetsera madzi cha polycarboxylate chomwe chimagwiritsidwa ntchito kawirikawiri chimakhala ndi mpweya wina, ndipo mpweya wa konkire suyenera kukhala wokwera kwambiri, mwinamwake mphamvu ya konkire idzachepetsedwa kwambiri.

c. Kusunga madzi.

Ma superplasticizers samathandizira kwambiri kuchepetsa magazi a konkriti, ndipo amathanso kuonjezera kutuluka kwa magazi. Kutaya magazi konkriti kumawonjezeka pamene mlingo uli wochuluka.