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Umhla wokuPosa:3, Sep, 2024

 

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7. Impembelelo yokuxuba ixesha kunye nesantya sokuxuba

Ixesha lokuxuba linempembelelo ngokuthe ngqo kumxholo wekhonkrithi kunye nefuthe le-dispersion ye-concrete admixtures kwi-concrete, kwaye ichaphazela ngokungathanga ngqo ukusebenza, iimpawu zoomatshini kunye nokuqina kwekhonkrithi. Ukuba umxube ubaleka ngokukhawuleza, kulula ukonakalisa isakhiwo se-colloidal kwi-samente kunye ne-membrane yombane ephindwe kabini kumphezulu wamasuntswana e-samente, eya kuthi ekugqibeleni ichaphazele ixesha lokumisela kunye nokudilika kwekhonkrithi kumlinganiselo omkhulu. Isantya sokuxuba kufuneka silawulwe ngaphakathi kwe-1.5-3 imizuzu. Ukuba indlela yokuxuba eyomileyo isetyenzisiweyo, ikhonkrithi inokuxutywa ngokulinganayo ngokusebenzisa umnciphisi wamanzi ngokufanelekileyo. Ukuba isisombululo kufuneka songezwe, amanzi kufuneka ahlanjululwe ekuxubeni ngexesha lokucwangciswa komnciphisi wamanzi ukuze kuqinisekiswe ukulungelelaniswa koyilo lwe-samente yamanzi. Ukuze kuqinisekiswe ukuchithwa kwekhonkrithi kwaye unike umdlalo opheleleyo kwindima yokunciphisa amanzi, indlela yokuxuba i-post-mixing ingasetyenziswa ngokuthe ngqo. Ukwahluke kwindlela yokongeza yokunciphisa amanzi, ukukhululeka kokuxuba ikhonkrithi kunokuqinisekiswa ngokusebenzisa indlela yokuxuba emva kokuxuba ngokufanelekileyo. Ukuba ilori yokuxuba iyadingeka ukuthutha ikhonkrithi, isinciphisi samanzi singongezwa kwilori yokuxuba imizuzu emi-2 ngaphambi kokukhulula ukunyusa ngokufanelekileyo isantya sokuxuba kwilori yokuxuba kunye nokuphucula umphumo wokukhupha.

8. Impembelelo yobushushu be-ambient kunye nokufuma

Ixesha lokumisela, ukuqina kwesantya kunye namandla okuqala okuxutywa kwekhonkrithi kuhambelana ngokuthe ngqo nobushushu bokunyanga. Emva kokongeza umnciphisi wamanzi, le nto ibonakala ngokucacileyo, kwaye umphumo uya kuba mkhulu ngakumbi xa ixesha lokumisa lingaphantsi kwama-20 degrees Celsius. Ngokuqhelekileyo, okukhona iqondo lobushushu liphezulu, kokukhona ukukhawuleza kwesantya sokugalela kwesamente, kwaye okukhona isantya sokumka komphunga siya kuba njalo. Amanzi akhululekile ngaphakathi kwekhonkrithi aya kudityaniswa ngokuqhubekayo kwi-concrete surface ngokusebenzisa i-capillary, ngokuqhubekayo ukukhawuleza umphumo we-hydration we-cement. Amanzi asimahla kwikhonkrithi aphuphuma kwaye ancitshiswe, nto leyo ebangela ukulahleka kwe-slump yekhonkrithi. Ukongeza, isiphumo sokubambezeleka kwezinye izinto ezixubeneyo zekhonkrithi ziya kuncitshiswa kakhulu ngaphezulu kwama-30 degrees Celsius. Ngoko ke, ukuba kuyimfuneko ukusebenza kwindawo yokushisa ephezulu, kuyimfuneko ukwandisa ngokufanelekileyo inani le-concrete admixtures ukuze ugweme ngokufanelekileyo ukwenzeka kokuphuma kwamanzi. I-Wood calcium inepropathi ethile yokucotha. Inokuba namandla athile okwakheka emva kokugalela ixesha elide. Ngexesha lomsebenzi wokulondoloza, kuyimfuneko ukwandisa ixesha lokumisa i-static ngokwaneleyo kwaye uyilo ngokwesayensi idosi. Ngaphandle koko, ikhonkrithi ixhomekeke kwiintanda ezinzulu, ukukhululeka komphezulu kunye ne-bulging ngexesha lokusetyenziswa. Kwinkqubo yokusebenzisa isinciphisi samanzi esisebenza kakuhle kakhulu, ngenxa yokunyanzeliswa komoya ophantsi, isiphumo sokucotha esicothayo asinakuqinisekiswa, kwaye ixesha elide lokumisa i-static alidingeki ngexesha lenkqubo yokunyanga umphunga. Ngoko ke, kwinkqubo yokongeza i-admixtures, umsebenzi ofanelekileyo wokulondoloza kufuneka wenziwe ngokucophelela ukuze ugweme ukukhuphuka kwamanzi amaninzi ngexesha lokugcinwa.

9. Ixesha lokugcina isamente

Ngaphantsi kweemeko eziqhelekileyo, ixesha elifutshane lokugcina i-samente, liya kubonakala lihlaziyekile, kwaye i-plasticization effect ye-samente iya kuba yimbi. Okukhona i-samente isentsha, kokukhona itshajiswa ngamandla, kwaye kokukhona izibhengeza ii-ionic surfactants. Kwisamente esandul 'ukucutshungulwa, izinga layo lokunciphisa amanzi liphantsi kwaye ilahleko ye-slump ikhawuleza. Ngesamente enexesha elide lokugcina, ezi ngxaki zinokuphetshwa kakuhle.

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10. Umxholo we-alkali kwisamente

Umxholo we-alkali nawo unefuthe elithe ngqo kwi-adaptation ye-samente kunye nokunciphisa amanzi. Njengoko umxholo we-alkali wesamente usanda, umphumo weplastiki wesamente uya kuhla. Xa umxholo we-alkali udlula uluhlu oluthile, luya kuba nefuthe elibi kakhulu kwixesha lokumisela kunye nokudilika kwesamente. Ukongeza, ifom yealkali kwisamente nayo inefuthe elithe ngqo kwisiphumo sokusetyenziswa kokunciphisa amanzi. Kwiimeko eziqhelekileyo, ukuba i-alkali ikhona ngendlela ye-sulfate, umphumo wayo kwi-reducers yamanzi ingaphantsi kweyona ndlela ye-hydroxide.

11. Igypsum kwisamente

Ngokudibanisa i-samente ye-gypsum kwi-samente, i-hydration ye-samente inokulibaziseka kakhulu, kwaye i-adsorption ngqo ye-samente kunye nokunciphisa amanzi inokuphetshwa, ngaloo ndlela iphucula ngokufanelekileyo ukulungelelaniswa kwesamente kunye nesinciphisi samanzi. Ngokwenani elikhulu lezifundo, emva kokongeza inani elithile le-gypsum kwi-samente, i-adsorption yokunciphisa amanzi kwi-cement mineral C3A inokunciphisa ngokufanelekileyo. Oku kungenxa yokuba i-gypsum kunye ne-C3A inokusabela ukwenza i-calcium sulfonate, eya kuthi igubungele ngokuthe ngqo indawo ye-C3A, igweme ukugqithiswa okungaphezulu kwe-C3A, okunokuthi buthathaka kakhulu ukungeniswa kwamasuntswana e-C3A kwi-reducer yamanzi. Iindidi ezahlukeneyo zegypsum zinemigangatho eyahlukeneyo yokuchithwa kunye ne-solubilities. Uhlobo kunye nomxholo we-samente ye-gypsum inefuthe elithe ngqo kwi-adaptation phakathi kwe-samente kunye nesinciphisi samanzi. I-pore fluid sulfate kwikhonkrithi yesamente ngokuyinhloko ivela kwi-sulfate eyenziwe yi-silicate sement, eya kuba nefuthe elithe ngqo kwi-sement hydration reaction kunye nokusebenza kwekhonkrithi ye-silicate. Iiion ze-sulfate kwi-gypsum zihlala zitshintsha ngeendlela ezahlukeneyo ngexesha lokugaya. Ukuba ubushushu benkqubo yokugaya buphezulu, i-dihydrate gypsum iya kuchithwa ngokuyinxenye kwaye yenze i-hemihydrate gypsum. Ukuba iqondo lokushisa ngaphakathi kwelitye liphezulu kakhulu, inani elikhulu le-hemihydrate gypsum liya kwenziwa kule nkqubo, eya kuthi ekugqibeleni iholele ekubeni kwenzeke i-sement pseudo-setting. Kwisamente enamacandelo e-alkaline sulfate encinci, phantsi kwe-adsorption eyomeleleyo ye-sulfonic acid-based reducers yamanzi, iya kubangela ngokuthe ngqo i-concrete slump ngokukhawuleza. Xa umxholo we-soluble sulfate usanda, i-adsorption ye-high-effective reducers yamanzi iya kubonisa i-quasi-linear trend downwarding.

12. Izixhobo zokugaya isamente

Umphumo wokugaya isamente unokuphuculwa kakhulu ngokusebenzisa izixhobo zokugaya isamente ngokufanelekileyo. Kwinkqubo yokuveliswa kwesamente kwiinkampani ezininzi zesamente zangaphandle, izixhobo zokugaya zidla ngokusetyenziswa ngobuninzi. Kwiminyaka yakutshanje, emva kokuphunyezwa kwemigangatho emitsha yesamente kwilizwe lam, iimfuno zamandla kunye nokucolwa kwesamente ziye zaphuculwa, eziye zabeka phambili iimfuno eziphezulu zokusetyenziswa kwezixhobo zokugaya. Okwangoku, kukho iintlobo ezininzi zokuncedisa i-samente, kwaye inani labavelisi bokuncedisa kwilizwe lam libonisa umkhwa wokunyuka okuqhubekayo. Abavelisi boncedo lokusila abahlukeneyo besamente baqhubekile betyala imali kuphando nophuhliso lwezixhobo zokusila ezinoqoqosho, ezisebenzayo nezilula ukuzisebenzisa. Nangona kunjalo, abanye abavelisi boncedo lokusila banika ingqwalaselo eninzi kakhulu kwiindleko zemveliso kwaye batyala imali encinci kuphando lwentsebenzo yoncedo lokusila, enesiphumo esibi kakhulu kwisiphumo sokusetyenziswa kwayo: ① Ukusetyenziswa kwezinto eziqulethe iityuwa zehalogen kusenokwenzeka ukuba kubangele umhlwa. imivalo yentsimbi ngaphakathi kwekhonkrithi. ② Ukusetyenziswa kwe-lignin sulfonate eninzi kukhokelela kwingxaki enkulu yokungahambelani phakathi kwesamente kunye nemixube yekhonkrithi. ③ Ukuze kuncitshiswe ngempumelelo iindleko zemveliso, isixa esikhulu senkunkuma yamashishini sisoloko sisetyenziswa, esinesiphumo esibi kakhulu ekomeleleni kwekhonkrithi. Kwinkqubo yokuvelisa ikhonkrithi yangoku, umxholo we-alkali kunye ne-chloride ion, uhlobo lwe-gypsum, kunye neeminerali ze-clinker zinefuthe elithe ngqo ekuhanjisweni kweengqungquthela zesamente. Ekusetyenzisweni kwezixhobo zokugaya, ukuqina kwe-samente akunakubangwa. Ukubunjwa kwezinto ezincedisayo zokugaya kunzima. Kuphela ngokusebenzisa izixhobo zokugaya ngokufanelekileyo kuya kuqinisekiswa umphumo wekhonkrithi. Ngexesha lenkqubo yokuvelisa, abavelisi boncedo lokusila kufuneka babe nokuqonda okupheleleyo kwenkqubo yokusila yenkampani, kwaye balawule iintlobo zoncedo lokusila kunye nokuhlelwa kwamasuntswana esamente.

13. Umlinganiselo womxube wokwakha

Umlinganiselo womxube wokwakha ungowengxaki yoyilo lobunjineli, kodwa unempembelelo ethe ngqo ekuhambelaneni kwe-concrete admixtures kunye nesamente. Ngokutsho kwedatha echaphazelekayo, ukuba umlinganiselo wesanti uphezulu kakhulu, kulula ukubangela ukuba i-fluidity yomxube wekhonkrithi iyancipha, kwaye ilahleko ye-slump inkulu kakhulu. Ukongezelela, imilo, ukuxutywa kwamanzi kunye nokuhlelwa kwamatye kwi-concrete mix ratio kuya kuchaphazela ukwakhiwa, ukugcinwa kwamanzi, ukudibanisa, umbane kunye nokwakheka kwekhonkrithi ukuya kwinqanaba elithile. Uvavanyo olufanelekileyo lubonisa ukuba ngokunciphisa umlinganiselo wesamente yamanzi, amandla ekhonkrithi anokuphuculwa kwinqanaba elithile. Ngaphantsi kwemeko yokusetyenziswa kwamanzi ngokufanelekileyo, iipropati ezahlukahlukeneyo zekhonkrithi zesamente zingasetyenziswa ngokupheleleyo, ukwenzela ukuba iplastiki yayo iphuculwe ngokupheleleyo, ukuxinwa kwe-admixtures kunokuqinisekiswa, kunye nokuhambelana kwe-admixtures kunye ne-samente kunokuphuculwa.


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  • Ixesha lokuposa: Sep-03-2024