Tsiku Lotumiza:14,Mar,2022

Kusakaniza kumatanthauzidwa ngati zinthu zina osati madzi, ma aggregates, hydraulic cementitious material kapena fiber reinforcement yomwe imagwiritsidwa ntchito ngati chophatikizira cha cementitious osakaniza kuti asinthe zinthu zake zatsopano zosakaniza, zokhazikika kapena zowumitsidwa ndipo zimawonjezeredwa ku batch isanayambe kapena panthawi yosakaniza. . Monga tafotokozera mu Gawo 1, kusakaniza kwa mankhwala kumatanthauzidwanso kuti sipozzolanic (sifuna calcium hydroxide kuti igwirizane) mu mawonekedwe a madzi, kuyimitsidwa kapena osungunuka m'madzi.

Kuchepetsa madzi admixtures bwino pulasitiki konkire (yonyowa) ndi anaumitsa katundu, pamene anapereka-kulamulira admixtures ntchito konkire kuikidwa ndi kumalizidwa zina kuposa momwe akadakwanitsira kutentha. Zonse ziwiri, zikagwiritsidwa ntchito moyenera, zimathandizira kuti pakhale njira zabwino zopangira konkriti. Komanso, zosakaniza zonsezi ziyenera kukwaniritsa zofunikira za ASTM C 494 (onani Table 1).

Zosakaniza Zochepetsa Madzi

Zochepetsa madzi zimachita izi: kuchepetsa kuchuluka kwa kusakaniza kwamadzi komwe kumafunikira kuti muchepetse kutsika. Izi zingapangitse kuchepa kwa madzi-cementitious ratio (w / c ratio), zomwe zimapangitsa kuti pakhale mphamvu zowonjezera komanso konkire yokhazikika.

Kuchepetsa w / c chiŵerengero cha konkire kwadziwika kuti ndi chinthu chofunika kwambiri pakupanga konkire yokhazikika, yapamwamba kwambiri. Kumbali inayi, nthawi zina simenti imatha kutsitsidwa ndikusunga chiŵerengero choyambirira cha w/c kuti muchepetse mtengo kapena kutentha kwa hydration kutsanulira konkire.

Zosakaniza zochepetsera madzi zimachepetsanso tsankho ndikuwongolera kuyenda kwa konkriti. Chifukwa chake, amagwiritsidwanso ntchito popanga konkriti.

Zosakaniza zochepetsera madzi nthawi zambiri zimagawika m'magulu atatu: otsika, apakatikati ndi apamwamba. Maguluwa amachokera pamtundu wa kuchepetsa madzi kwa admixture. Peresenti ya kuchepetsa madzi ikugwirizana ndi madzi osakaniza oyambirira omwe amafunikira kuti apeze kutsika (onani Table 2).

Ngakhale zochepetsera madzi zonse zimakhala ndi zofanana, aliyense ali ndi ntchito yoyenera yomwe ili yoyenera kwambiri. Table 3 ikupereka chidule cha mitundu itatu ya zosakaniza zochepetsera madzi, madera awo ochepetsera madzi ndi ntchito zawo zoyambirira. Zotsatira zawo pamayendedwe a mpweya zimasiyana malinga ndi chemistry.

Momwe amagwirira ntchito

Simenti ikakumana ndi madzi, zida zamagetsi zofananira pamwamba pa tinthu tating'onoting'ono ta simenti zimakopana, zomwe zimapangitsa kuti tinthu tating'onoting'ono tidutse. Gawo labwino la madzi limalowetsedwa munjira iyi, potero limatsogolera kusakanikirana kophatikizana ndikuchepetsa kutsika.

Kuchepetsa madzi admixtures kwenikweni kuchepetsa pamwamba pamwamba pa zolimba particles ndi kuchititsa onse pamwamba kunyamula ngati ndalama. Popeza tinthu tating'onoting'ono tofanana timathamangitsana, timachepetsa kusefukira kwa tinthu ta simenti ndikulola kubalalitsidwa bwino. Amachepetsanso kukhuthala kwa phala, zomwe zimapangitsa kutsika kwakukulu.

Table 4 ikuwonetsa zina mwazinthu zomwe zimagwiritsidwa ntchito pamtundu uliwonse wa zochepetsera madzi. Zigawo zina zimawonjezedwa kutengera mankhwala ndi wopanga. Zosakaniza zina zochepetsera madzi zimakhala ndi zotsatira zachiwiri kapena zimaphatikizidwa ndi ma retarders kapena ma accelerator.