iindaba

ikhonkrithi1

Isixa sokuxuba sokunciphisa amanzi sidlula isixa esiqhelekileyo sokuxuba ngamaxesha amaninzi, kwaye impembelelo yalo ekusebenzeni kwekhonkrithi kufuneka inqunywe ngokwemeko ethile.

Kwimeko yokuqala, kwikhonkrithi ye-ultra-high-strength, kuba umlinganiselo we-binder wamanzi ngu-≤0.3 okanye ungaphantsi kwe-0.2, ngokuqhelekileyo ibonisa ukuba imeko yekhonkrithi ayinakukhathazeka kwisixa se-concrete.i-arhente yokunciphisa amanzi. Ukuze kuphunyezwe imo efanelekileyo yamanzi, amanzi ayancipha. Idosi ye-ejenti idla ngokuphindwe ka-5-8 kwidosi eqhelekileyo, oko kukuthi, idosipolycarboxylic acidifuna ukufikelela kwi-5% -8%. Kwikhonkrithi engaphantsi kweC50, umxholo ophezulu onjalo uyinto engakholelekiyo. Nangona kunjalo, iziphumo zovavanyo zibonisa ukuba amandla ekhonkrithi kwinqanaba ngalinye likhula kakuhle phantsi kwesi sixa, kwaye amandla angama-28d ekhonkrithi alungiswa ngale mandla amakhulu kune-100MPa.

Isizathu kukuba: ukusasazwa kwei-arhente yokunciphisa amanzikwisamente yintengiso yomzimba kuphela.I-arhente yokunciphisa amanziiimolekyuli adsorbed kumphezulu amasuntswana isamente. Ngokuthintelwa kwe-steric kunye ne-electrostatic repulsion, i-flocculation structure ye-cement particles iyachithwa kwaye amanzi akhululekile akhululwa. , Ngaloo ndlela kwandisa ubumanzi bekhonkrithi, kwaye ngenxa yesakhiwo sayo esikhethekileyo sekama, ipolycarboxylic acidisekelwei-arhente yokunciphisa amanziinokuthintela amaqhekeza e-samente ukuba aphinde adibanise phakathi kwexesha elithile, ngoko inomsebenzi wokugcinwa kwe-slump. Emva kokuba ixesha elithile lidlulile, imveliso ye-cement hydration iya kusonga ngokupheleleyoi-arhente yokunciphisa amanziiimolekyuli adsorbed kumphezulu amasuntswana isamente. Emva kwei-arhente yokunciphisa amanziiimolekyuli zikhuselwe, ukusasazeka kuyanyamalala ngokupheleleyo, kwaye ke akusekho nayiphi na impembelelo okanye impembelelo kwikhonkrithi. Isamente idla ngokuba ngamanzi Amandla ekhonkrithi akhula ngokwesiqhelo.

Ngokuqinisekileyo, ngenxa yomxholo ophezulu wei-arhente yokunciphisa amanzi, Ugxininiso lwei-arhente yokunciphisa amanziiimolekyuli kwikhonkrithi inkulu. Emva kokuba ezinye iimolekyuli zigutyungelwe yimveliso ye-samente hydration, iimolekyuli ezintsha zibhengezwa kumphezulu weemveliso zesamente ze-samente, zikhusela amasuntswana esamente ukuba agqithe ngokukhawuleza. Inethiwekhi yenziwe, eyandisa ixesha lokumisela kwinqanaba elithile, kodwa ukusetwa kwesamente ngokubanzi akuyi kudlula i-24h.

Kwimeko yesibini, ii-arhente yokunciphisa amanzingokwayo ineempawu ezithile zokungenisa umoya kunye nokubuyisela umva, kwaye amaxesha amaninzi e-over-admixture ingaba nefuthe elibi kakhulu ekusebenzeni kwekhonkrithi. Ngokubanzi, ubungakanani becandelo lokubuyiswa bumiselwa ngokwemekobume yobushushu, iimfuno zobunjineli kunye nedosi eqhelekileyoi-arhente yokunciphisa amanzi. I-Adsorption ichaphazela i-hydration eqhelekileyo yezinto ze-cementitious. Kwimeko ekhaphukhaphu, ixesha lokumisela lide kakhulu, kwaye kwimeko embi kakhulu, ikhonkrithi ayiyi kumisa iintsuku eziliqela okanye ngokusisigxina. Ngokuqhelekileyo, kwikhonkrithi ebekwe iintsuku ezi-2 okanye ixesha elide, ngenxa yokulibaziseka okugqithisileyo kwenkqubo ye-hydration, uhlobo kunye nobuninzi beemveliso ze-hydration ziya kutshintsha, okukhokelela ekuhlahleni okusisigxina kumandla ekhonkrithi. Kakade ke, kwindlela kaloliwe evala iimfumba (idla ngokuba yi-72-90h ukusetwa kokuqala) kunye nolwakhiwo olunzima lwekhonkrithi olufana neziseko zeengqumba, iikepusi, amadama, njl.njl., ixesha elide lokumisa liyafuneka. Ngokuqhelekileyo, umgangatho wamandla kufuneka unyuswe ngokufanelekileyo ngexesha loyilo lomxube womxube. Qinisekisa ukuba amandla e-28d ahlangabezana neemfuno zoyilo.

I-air-entrainingi-arhente yokunciphisa amanziixutywe kakhulu amaxesha amaninzi. Xa umxholo womoya wekhonkrithi ufanelekile kwizinga eliqhelekileyo lokuxuba, umxholo womoya uya kwandiswa kakhulu emva kokuba uxutywe kakhulu ngamaxesha amaninzi. I-concrete slurry inobutyebi obungaqhelekanga, kwaye ikhonkrithi ilula kwaye iyadada xa ihlatywe, yinto enzulu Xa ikhonkrithi ikhululekile kwaye i-porous njengesonka, amandla ekhonkrithi ayancipha kakhulu.

Kwimeko yesithathu, nokuba ii-arhente yokunciphisa amanzingokwayo ayinayo i-air-entraining kunye ne-retading type, emva kokuphindaphinda kabini, ukuba ukusetyenziswa kwamanzi akulungiswanga ngexesha, ukusebenza kwekhonkrithi entsha kunokonakala kakhulu, kubangele ukufihla okukhulu. Amanzi, ulwahlulo, ukubamba umphantsi, ukuqina, njl., kunye nokungahambelani kakuhle kunye nokuzinza emva kokuthululwa, kunye ne-delamination yangaphakathi, ekhokelela ekwandeni komlinganiselo wamanzi-to-binder wekhonkrithi ejikeleze ibha yensimbi, kunye nokuncipha kwamandla. , eyenza ukuba amandla okubambelela kwintsimbi yentsimbi ehle kakhulu. Inani elikhulu lokopha okubangelwa kukuxutywa okugqithisileyo kuya kubonakala kumphezulu wekhonkrithi kunye namalungu adityaniswa ne-formwork, okubangela ukuncipha kwamandla ezi nxalenye, kunye nenani elikhulu leziphene ezifana nokuqhekeka, ama-honeycombs, kunye neendawo ezifakwe kwi-pockmarked zivame ukubonakala xa ukubunjwa kususiwe, okwenza ukuba amandla aphathekayo axhathise ukhukuliseko lwangaphandle Ukunciphisa kakhulu, kuchaphazela kakhulu ukuqina kwekhonkrithi.


  • Ngaphambili:
  • Okulandelayo:

  • Ixesha lokuposa: Dec-02-2021