1 Lub zog tsis yog raws li qhov yuav tsum tau ua
1.1.1 Cov khoom siv vim li cas
Cement pob zeb raw cov ntaub ntawv, cement yog nws cov khoom tseem ceeb. Cov cement thiab dej tsim cov slurry uas coats thiab sau cov aggregate, lubricating nws ua ntej hardening thiab khi nws ua ke rau hauv ib tug tag nrho cov khoom. Txawm hais tias cov cement tuaj yeem sib sau ua ke ruaj khov ua ke yog qhov tseem ceeb los txiav txim siab qhov zoo ntawm cov cement pob zeb. Portland cement yog tam sim no feem ntau siv, thiab nws cov kev ua tau zoo yog txiav txim siab los ntawm cov ntxhia hauv cov khoom tseem ceeb ntawm nws cov khoom tseem ceeb. Cement los ntawm qhov pib ntawm kev sib xyaw rau kev tsim cov pob zeb nyuaj cement, yog ib qho kev ua haujlwm tas mus li, kev siv lub cev thiab tshuaj lom neeg, muab faib ua condensation thiab hardening ob txheej txheem, kev cuam tshuam ntawm cement condensation hardening yam tseem ceeb yog kub thiab av noo.
1.1.2 Cov laj thawj ntawm kev tu
React nrog dej rau cement hydrates tsim, cement hais nyob ib ncig ntawm cov tshuaj sai sai ua supersaturated tov ntawm hydrates, nag lossis daus hydrated calcium silicate gel, hydrated calcium aluminate nyob rau hauv cov cement hydration khoom, xws li pob khoom nto, nrog rau lub sij hawm, lub ntuj tshiab. gas hydrates, lub ntuj gas hydrates zaj duab xis txheej thickening, nqaim qhov sib txawv ntawm cov khoom, condenses rau hauv qhov chaw ntawm lub ntxeem tau network. Nrog rau cov dej tsis tu ncua, cov khoom hydrate nce ntxiv, thiab qhov chaw sib cuag ntawm cov khoom yog nce, uas ua rau cov qauv ntau ntom thiab lub zog kuj tseem txhim kho raws li. Tab sis lub caij ntuj sov kub yog siab, muaj peev xwm ua tau raws li qhov yuav tsum tau ntawm cov cement hardening, tab sis nyob rau tib lub sij hawm noo noo evaporation yog ceev heev, cov hydration cov tshuaj tiv thaiv ntawm cement thiab dej nyob rau hauv lub tshiab pouring qhob tsis tau tag nrho, noo noo tsis tau, lub zog ntawm cov cement tsis tuaj yeem loj hlob, lub zog ntawm pob zeb tsis tuaj yeem lav.
