Cov tshauv ya Portland cement

Portland Cement
Cov tshauv ya Cov cement portland yog hais txog kev sib xyaw ua ke ntawm Portland cement clinker thiab cov tshauv ya, sib xyaw nrog cov gypsum kom tsim nyog thiab tom qab ntawd av, codenamed PF Txhua yam khoom siv hydraulic cementitious ua los ntawm Portland cement clinker, tshauv ya thiab cov av gypsum kom tsim nyog hu ua tshauv ya Portland cement, codenamed PF Tus nqi ntawm cov tshauv ya ntxiv rau cov cement yog 20% ​​~ 40% los ntawm pawg, thiab nws qib zog thiab cov kev xav tau ntawm txhua lub hnub nyoog yog tib yam li cov ntawm slag Portland cement.

Cov khoom siv raw
Nws yog ua los ntawm Portland cement clinker thiab cov tshauv ya, sib xyaw nrog cov gypsum kom txaus thiab tom qab ntawd sib tsoo. Code PF
Txhua yam khoom siv hydraulic cementitious ua los ntawm Portland cement clinker, fly ash thiab qhov ntau ntawm gypsum av tsim nyog hu ua fly ash Portland cement, codenamed PF. Tus nqi ntawm fly ash ntxiv rau cov cement yog 20% ​​txog 40% los ntawm qhov hnyav. Nws raug tso cai koom nrog hauv granulated blast furnace slag tsis pub tshaj 1/3 ntawm tag nrho cov khoom sib xyaw. Lub sijhawm no, tag nrho cov khoom sib xyaw tuaj yeem ncav cuag 50%, tab sis tus nqi ntawm fly ash yuav tsum tsis pub tsawg dua 20% lossis ntau dua 40%.
Cov yam ntxwv
Cov qauv ntawm cov cement tshauv ya yog qhov ntom ntom, thaj chaw sab hauv tshwj xeeb yog me me, thiab lub peev xwm adsorption rau dej yog me dua, thiab qhov xav tau dej rau cov cement hydration yog me me, yog li qhov qhuav shrinkage ntawm cov cement tshauv ya yog me me, thiab qhov tsis kam tawg kuj tsawg. Zoo. Tsis tas li ntawd, zoo ib yam li cov cement dav dav sib xyaw nrog cov khoom sib xyaw ua ke, nws muaj cua sov qis thiab muaj zog tiv thaiv corrosion.
Kev ua tau zoo
Cov yam ntxwv tshwj xeeb ntawm cov tshauv ya Portland cement yog raws li nram no:
(1) Lub zog thaum ntxov yog qis, thiab qhov nce ntawm lub zog lig yog loj: lub zog thaum ntxov ntawm cov cement tshauv ya yog qis, thiab lub zog thaum ntxov txo qis ntau nrog rau qhov nce ntawm cov tshauv ya. Vim tias lub cev vitreous hauv cov tshauv ya ruaj khov heev, cov hmoov tshauv ya raug eroded thiab rhuav tshem qeeb heev los ntawm Ca (OH) 2 thaum lub sijhawm hydration ntawm cov cement tshauv ya, yog li qhov kev txhim kho lub zog ntawm cov cement tshauv ya feem ntau yog pom tseeb hauv theem tom qab. , nws qhov nce ntawm lub zog lig yog loj, thiab nws tuaj yeem tshaj qhov lub zog lig ntawm cov cement Portland sib xws.
(2) Ua haujlwm tau zoo thiab me me qhuav ntsws: Vim tias feem ntau ntawm cov hmoov tshauv ya tau kaw thiab khov kho, thiab thaj chaw sab hauv thiab cov dej nqus dej ib leeg me me, cov hmoov tshauv ya tau ua haujlwm tau zoo thiab me me qhuav ntsws. , muaj cov yam ntxwv ntawm lub zog tensile siab thiab tiv taus tawg zoo. Qhov no yog qhov zoo ntawm cov hmoov tshauv ya.
(3) Kev tiv thaiv xeb zoo: cov cement tshauv ya muaj kev tiv thaiv xeb siab rau dej tshiab thiab sulfate. Vim yog kev sib xyaw ua ke ntawm SiO2 nquag hauv cov tshauv ya thiab Ca (OH) 2, calcium silicate hydrate yog tsim thaum sib npaug. Qhov concentration txwv tsis pub tshaj plaws (piv txwv li alkalinity theem kua) qis dua li qhov xav tau rau qhov sib npaug ntawm calcium silicate hydrate hauv cov cement Portland ib txwm muaj, yog li tus nqi leaching hauv dej tshiab raug txo qis, yog li txhim kho qhov kev tiv thaiv cement. Kev muaj peev xwm xeb dej tshiab thiab tiv thaiv kev puas tsuaj sulfate.
(4) Qhov kub tsawg ntawm kev ua kom noo noo: Qhov ceev ntawm kev ua kom noo noo ntawm cov tshauv ya yog qeeb thiab qhov kub ntawm kev ua kom noo noo yog qis, tshwj xeeb tshaj yog thaum qhov ntau ntawm cov tshauv ya ntxiv yog loj, qhov txo qis ntawm qhov kub ntawm kev ua kom noo noo yog qhov pom tseeb heev.

Cov cement Portland
Tag nrho cov Portland cement clinker feem ntau yog ua los ntawm calcium silicate, limestone lossis granulated blast furnace slag uas muaj tsawg dua 5%, thiab cov khoom siv hydraulic cementitious ua los ntawm finely ground gypsum yog hu ua Portland cement. Thoob ntiaj teb hu ua Portland Cement.
Kev faib tawm
Portland cement muab faib ua ob hom, hom I Portland cement uas tsis muaj cov khoom sib xyaw hu ua Portland cement, code P·I; cov khoom sib xyaw nrog limestone lossis granulated blast furnace slag tsis pub tshaj 5% ntawm cov cement pawg hu ua II Hom Portland cement, code P·II.
Cov khoom xyaw ntawm cov zaub mov
Cov khoom siv tseem ceeb ntawm Portland cement yog: tricalcium silicate, dicalcium silicate, tricalcium aluminate, thiab tetracalcium ferric aluminate. Tricalcium silicate txiav txim siab lub zog ntawm Portland cement hauv plaub lub lis piam; dicalcium silicate tsuas yog siv nws lub zog tom qab plaub lub lis piam, thiab ncav cuag lub zog ntawm tricalcium silicate rau plaub lub lis piam hauv kwv yees li ib xyoos; lub zog ntawm tricalcium aluminate Nws siv sai dua, tab sis lub zog qis, thiab nws ua lub luag haujlwm tshwj xeeb hauv lub zog ntawm Portland cement hauv 1 txog 3 hnub lossis ntev dua me ntsis; Lub zog ntawm cov kua qaub ntsev cement yog me me.