1. Uhlolojikelele lwe-cellulose ether (HPMC)
I-Hydroxypropyl methylcellulose (HPMC) iyinhlanganisela ye-cellulose ether evame ukusetshenziswa, eguqulwa ngamakhemikhali isuka ku-cellulose yemvelo. Inezindawo ezinhle kakhulu zokuncibilika kwamanzi, ukwakheka kwefilimu, ukuqina nokunamathela, ngakho-ke isetshenziswa kabanzi ezintweni zokwakha. Ukusetshenziswa kwe-HPMC ezintweni ezisekelwe kusimende ikakhulukazi ukuthuthukisa ukugeleza kwayo, ukugcinwa kwamanzi kanye nokulungisa isikhathi sokusetha.
2.Inqubo eyisisekelo yokubeka usimende
Inqubo kasimende esabela emanzini ukuze kwakheke ama-hydrate ibizwa ngokuthi i-hydration reaction. Le nqubo ihlukaniswe izigaba eziningana:
Isikhathi sokungeniswa: Izinhlayiya zikasimende ziqala ukuhlakazeka, zakha i-calcium ion kanye ne-silicate ion, ebonisa isimo sokugeleza kwesikhashana.
Isikhathi sokusheshisa: Imikhiqizo ye-hydration ikhula ngokushesha futhi inqubo yokumisa iqala.
Isikhathi sokuncishiswa kwejubane: Izinga lokugeleza kwamanzi liyancipha, usimende uqala ukuqina, futhi kwakheka itshe eliqinile likasimende.
Isikhathi sokuzinzisa: Imikhiqizo ye-hydration iyavuthwa kancane kancane futhi amandla akhula kancane kancane.
Isikhathi sokusetha ngokuvamile sihlukaniswa sibe yisikhathi sokuqala sokusetha kanye nesikhathi sokusetha sokugcina. Isikhathi sokuqala sokusetha sibhekisela esikhathini lapho ukunamathisela usimende kuqala ukulahlekelwa ipulasitiki, futhi isikhathi sokugcina sokusetha sibhekisela esikhathini lapho unamathisele usimende ulahlekelwa ngokuphelele ipulasitiki futhi ingena esigabeni sokuqina.
3. Indlela yethonya le-HPMC ngesikhathi sokusetha usimende
3.1 Ukuqina komphumela
I-HPMC inomphumela wokujiya obalulekile. Ingakhuphula i-viscosity yokunamathisela usimende futhi yakhe uhlelo lwe-viscosity ephezulu. Lo mphumela wokuqina uzothinta ukuhlakazeka kanye ne-sedimentation yezinhlayiya zikasimende, futhi ngaleyo ndlela kuthinte ukuqhubeka kokusabela kwe-hydration. Umphumela wokuqina unciphisa izinga lokumiswa kwemikhiqizo ye-hydration ebusweni bezinhlayiya zikasimende, ngaleyo ndlela kubambezeleka isikhathi sokusetha.
3.2 Ukugcina amanzi
I-HPMC inomthamo omuhle wokugcina amanzi. Ukwengeza i-HPMC ekunamathisele usimende kungathuthukisa kakhulu ukugcinwa kwamanzi okunamathiselwe. Ukugcinwa kwamanzi aphezulu kungavimbela amanzi angaphezulu kukasimende ukuthi angahwamuki ngokushesha, ukuze kugcinwe amanzi akunamathisela usimende futhi andise isikhathi sokusabela kwe-hydration. Ukwengeza, ukugcinwa kwamanzi kusiza ukunamathisela usimende ukugcina umswakama ofanele ngesikhathi senqubo yokwelapha futhi kunciphise ingozi yokuqhekeka okubangelwa ukulahlekelwa kwamanzi kusenesikhathi.
3.3 Ukuncipha kwamanzi
I-HPMC ingenza ifilimu evikelayo emboze ingaphezulu lezinhlayiya zikasimende, ezizovimbela ukusabela kwe-hydration. Le filimu evikelayo ivimbela ukuthintana okuqondile phakathi kwezinhlayiya zikasimende namanzi, ngaleyo ndlela ibambezele inqubo ye-hydration kasimende futhi yandise isikhathi sokumisa. Lo mphumela wokulibaziseka ubonakala ikakhulukazi ku-HPMC yesisindo samangqamuzana aphezulu.
3.4 I-thixotropy ethuthukisiwe
Ukwengezwa kwe-HPMC kungabuye kuthuthukise i-thixotropy ye-cement slurry (okungukuthi, ukukhuphuka kwamanzi kuyanda ngaphansi kwesenzo samandla angaphandle futhi kubuyele esimweni sokuqala ngemva kokususwa kwamandla angaphandle). Le mpahla ye-thixotropic isiza ukuthuthukisa ukusebenza kwe-simende slurry, kodwa mayelana nesikhathi sokumisa, le thixotropy ethuthukisiwe ingase ibangele udaka ukuthi lusabalalise ngaphansi kwe-shear force, iqhubeke yandise isikhathi sokumisa.
4. Ukusetshenziswa okungokoqobo kwe-HPMC okuthinta isikhathi sokumisa usimende
4.1 Izinto zokuzilinganisa phansi
Ezintweni ezizilinganisa phansi, usimende udinga isikhathi eside sokusetha sokuqala sokukala kanye nokusebenza kokuhlikihla. Ukwengeza i-HPMC kungandisa isikhathi sokuqala sokumisa usimende, okuvumela izinto ezizilinganisa zibe nesikhathi eside sokusebenza ngesikhathi sokwakha, kugwenywe inkinga ebangelwa ukumiswa ngaphambi kwesikhathi kodaka lukasimende ngesikhathi sokwakha.
4.2 Udaka oluxutshwe ngaphambilini
Odakeni oluxutshwe ngaphambili, i-HPMC ayithuthukisi kuphela ukugcinwa kwamanzi kodaka, kodwa futhi yandisa isikhathi sokusetha. Lokhu kubaluleke kakhulu ezikhathini ezinezokuthutha ezinde nesikhathi sokwakha, ukuqinisekisa ukuthi udaka lugcina ukusebenza kahle ngaphambi kokusetshenziswa nokugwema izinkinga zokwakha ezibangelwa isikhathi esifushane kakhulu sokusetha.
4.3 Udaka oluxutshwe okomile
I-HPMC ivamise ukungezwa odakeni oluxubile ukuze kuthuthukiswe ukusebenza kwayo kokwakha. Umthelela wokujiya we-HPMC ukhulisa i-viscosity yodaka, okwenza kube lula ukusebenzisa kanye nezinga ngesikhathi sokwakha, futhi andisa isikhathi sokumisa, okunikeza abasebenzi bokwakha isikhathi esanele sokwenza izinguquko.
5. Izinto ezithinta isikhathi sokumiswa kukasimende yi-HPMC
5.1 Inani elingeziwe le-HPMC
Inani le-HPMC elengeziwe liyisici esibalulekile esithinta isikhathi sokumisa usimende. Ngokuvamile, inani elikhulu le-HPMC elengeziwe, kusobala ngokwengeziwe ukunwetshwa kwesikhathi sokusetha sikasimende. Lokhu kungenxa yokuthi ama-molecule e-HPMC amaningi angavala izinhlayiya eziningi zikasimende futhi avimbele ukusabela kwe-hydration.
5.2 Isisindo se-molecular ye-HPMC
I-HPMC yezisindo zamangqamuzana ahlukene inemiphumela ehlukene ngesikhathi sokumisa usimende. I-HPMC enesisindo samangqamuzana aphezulu ngokuvamile inomphumela wokujiya onamandla namandla okugcina amanzi, ngakho ingandisa isikhathi sokusetha ngokuphawulekayo. Nakuba i-HPMC enesisindo esiphansi samangqamuzana ingase futhi yelule isikhathi sokusetha, umphumela awunamandla uma kuqhathaniswa.
5.3 Izimo zemvelo
Izinga lokushisa elizungezile kanye nomswakama kuzophinde kuthinte umphumela we-HPMC ngesikhathi sokusetha usimende. Ezimweni zokushisa okuphezulu, ukusabela kwe-cement hydration kuyasheshiswa, kodwa indawo yokugcina amanzi ye-HPMC ibambezela lo mphumela. Ezimweni zokushisa eziphansi, ukusabela kwe-hydration ngokwayo kuhamba kancane, futhi umphumela wokujiya nokugcina amanzi we-HPMC ungabangela isikhathi sokumisa usimende ukuba sinwetshwe kakhulu.
5.4 Isilinganiso samanzi nosimende
Izinguquko esilinganisweni samanzi nosimende zizophinde zithinte umphumela we-HPMC ngesikhathi sokusetha usimende. Ngesilinganiso esiphezulu samanzi-samende, kukhona amanzi amaningi kusimende unamathiselwe, futhi umphumela wokugcina amanzi we-HPMC ungase ube nomthelela omncane ngesikhathi sokusetha. Ngesilinganiso esiphansi sikasimende wamanzi, umphumela wokujiya we-HPMC uzoba sobala kakhulu, futhi umphumela wokwelula isikhathi sokusetha uzoba obaluleke kakhulu.
Njengesengezo esibalulekile sikasimende, i-HPMC ithinta kakhulu isikhathi sokumiswa kukasimende ngokusebenzisa izindlela ezihlukahlukene ezinjengokuqina, ukugcinwa kwamanzi, kanye nokuvinjelwa kokusabela kwe-hydration. Ukusetshenziswa kwe-HPMC kungandisa isikhathi sokuqala nesokugcina sokusetha sikasimende, kunikeze isikhathi eside sokusebenza sokwakha, futhi kuthuthukise ukusebenza kwezinto ezisekelwe kusimende. Ekusetshenzisweni okungokoqobo, izici ezifana nenani le-HPMC engeziwe, isisindo samangqamuzana, nezimo zemvelo ngokuhlanganyela zinquma umphumela wawo othize ngesikhathi sokumisa usimende. Ngokulungisa lezi zici ngokunengqondo, ukulawulwa okunembile kwesikhathi sokumisa usimende kungafinyelelwa ukuze kuhlangatshezwane nezidingo zamaphrojekthi wokwakha ahlukene.
Isikhathi sokuthumela: Jun-21-2024