Tsiku Lotumiza:30,Nov,2022

A. Njira yochepetsera madzi

Mmodzi wa ntchito zofunika wa madzi kuchepetsa wothandizira ndi kuchepetsa kumwa madzi konkire ndi kusintha fluidity wa konkire pansi chikhalidwe kusunga madzi binder chiŵerengero chosasinthika, kuti akwaniritse zofunika za kayendedwe konkire ndi kumanga. Zosakaniza zambiri zochepetsera madzi zimakhala ndi mlingo wokwanira. Ngati mlingo wokwanira wapitirira, kuchepetsa madzi sikudzawonjezeka, ndipo kutuluka kwa magazi ndi kulekanitsa kudzachitika. Mlingo wokwanira umagwirizana ndi zida zonse za konkriti komanso gawo losakanikirana la konkriti.

 

1. Naphthalene superplasticizer

Naphthalene superplasticizerzitha kugawidwa m'magulu akuluakulu (Na2SO4 okhutira <3%), mankhwala apakati (Na2SO4 okhutira 3% ~ 10%) ndi mankhwala otsika kwambiri (Na2SO4 okhutira> 10%) malinga ndi zomwe zili mu Na2SO4. Kuchuluka kwa mlingo wa naphthalene mndandanda wa madzi ochepetsera madzi: ufa ndi 0.5 ~ 1.0% ya misa ya simenti; Zomwe zili zolimba za yankho nthawi zambiri zimakhala 38% ~ 40%, kuchuluka kosakanikirana ndi 1.5% ~ 2.5% yamtundu wa simenti, komanso kuchepetsa madzi ndi 18% ~ 25%. Naphthalene mndandanda wamadzi chochepetsera satulutsa mpweya, ndipo sichikhudza nthawi yokhazikitsa. Zitha kuphatikizidwa ndi sodium gluconate, shuga, hydroxycarboxylic acid ndi mchere, citric acid ndi inorganic retarder, ndipo ndi kuchuluka koyenera kwa mpweya wolowetsa mpweya, kutayika kwa matope kumatha kuyendetsedwa bwino. The kuipa otsika ndende naphthalene mndandanda madzi reducer ndi kuti zili sodium sulphate ndi lalikulu. Kutentha kumatsika kuposa 15 ℃, sodium sulphate crystallization imachitika.

 

2. Polycarboxylic acid superplasticizer

Polycarboxylic acidchochepetsera madzi chimatengedwa ngati mbadwo watsopano wochepetsera madzi ochita bwino kwambiri, ndipo anthu nthawi zonse amayembekeza kuti azikhala otetezeka, ogwira mtima komanso osinthika kuposa njira yochepetsera madzi ya naphthalene yomwe ikugwiritsidwa ntchito. Ubwino wa polycarboxylic acid mtundu wochepetsera madzi umawonetsedwa makamaka mu: mlingo wochepa (0.15% ~ 0.25% (zolimba zosinthika), kuchuluka kwa madzi otsika (nthawi zambiri 25% ~ 35%), kusungika bwino, kuchepa pang'ono, mpweya wina. kuphunzitsidwa, komanso kukhala ndi alkali yochepa kwambiri.

Komabe, mukuchita,polycarboxylic acidmadzi ochepetsera adzakumananso ndi mavuto ena, monga: 1. Kuchepetsa madzi kumadalira zipangizo ndi kusakaniza gawo la konkire, ndipo amakhudzidwa kwambiri ndi silt zili mchenga ndi miyala ndi ubwino wa mchere admixtures; 2. Kuchepetsa kwa madzi ndi kusunga kutsika kumadalira kwambiri mlingo wa mankhwala ochepetsera madzi, ndipo n'zovuta kusunga kugwa ndi mlingo wochepa; 3. Kugwiritsira ntchito konkire kapena konkire yamphamvu kumakhala ndi kusakaniza kwakukulu, komwe kumakhudzidwa ndi kumwa madzi, ndipo kusinthasintha kochepa kwa madzi kungayambitse kusintha kwakukulu; 4. Pali vuto ngakhale ndi mitundu ina ya madzi kuchepetsa wothandizila ndi zina admixtures, kapena ngakhale palibe zotsatira superposition; 5. Nthawi zina konkire imakhala ndi madzi ambiri otaya magazi, mpweya wovuta kwambiri, ndi mathovu akuluakulu ndi ambiri; 6. Nthawi zina kutentha kusintha kungakhudze zotsatira zapolycarboxylic acidchochepetsera madzi.

Zinthu zomwe zimakhudza kuyanjana kwa simenti ndipolycarboxylic acidkuchepetsa madzi: 1. Chiŵerengero cha C3A / C4AF ndi C3S / C2S chikuwonjezeka, kugwirizanitsa kumachepa, C3A ikuwonjezeka, ndipo kumwa madzi konkire kumawonjezeka. Pamene zili zazikulu kuposa 8%, kutaya kwa konkire kumawonjezeka; 2. Zomwe zili zazikulu kapena zochepa kwambiri za alkali zingasokoneze kuyanjana kwawo; 3. Kusakanizika kwa simenti kumakhudzanso kugwirizana kwa awiriwo; 4. Mitundu yosiyanasiyana ya gypsum; 5. Kutentha kwakukulu kwa simenti kungayambitse kukhazikika kwachangu pamene kutentha kumaposa 80 ℃; 6. Simenti yatsopano ili ndi mphamvu yamagetsi yamphamvu komanso mphamvu yamphamvu yochepetsera madzi; 7. Malo enieni a simenti.