I-Methyl cellulose ether kuthempelesha yegumbi elapha ukhonkolo osebenza kakhulu

Abstract: Ngokushintsha okuqukethwe kwe-hydroxypropyl methylcellulose ether (HPMC) ekushiseni okuvamile okuphulukisa ukhonkolo we-ultra-high performance (UHPC), umphumela we-cellulose ether ku-fluidity, isikhathi sokusetha, amandla okucindezela, namandla okuguquguquka kwe-UHPC kwafundwa. , amandla e-axial tensile kanye nenani lokugcina eliqinile, futhi imiphumela yahlaziywa. Imiphumela yokuhlolwa ibonisa ukuthi: ukungeza okungaphezu kuka-1.00% we-HPMC ene-viscosity ephansi akuthinti uketshezi lwe-UHPC, kodwa kunciphisa ukulahlekelwa uketshezi ngokuhamba kwesikhathi. , futhi andise isikhathi sokumisa, ukuthuthukisa kakhulu ukusebenza kokwakha; lapho okuqukethwe kungaphansi kuka-0.50%, umthelela emandleni okucindezela, amandla e-flexural namandla e-axial tensile akubalulekile, futhi uma okuqukethwe kungaphezu kuka-0.50%, umshini wayo Ukusebenza kuncipha ngaphezu kwe-1/3. Uma kucatshangelwa ukusebenza okuhlukahlukene, umthamo onconyiwe we-HPMC ngu-0.50%.

Amagama angukhiye: ukhonkolo wokusebenza okuphezulu kakhulu; i-cellulose ether; ukuphulukiswa kwezinga lokushisa elivamile; amandla okucindezela; amandla e-flexural; amandla aqinile

0,Isandulelo

Ngokuthuthuka okusheshayo kwemboni yezokwakha yaseShayina, izidingo zokusebenza okukhonkolo kwezobunjiniyela bangempela nazo ziye zanda, futhi ukhonkolo osebenza kakhulu osezingeni eliphezulu (UHPC) ukhiqizwe ukuphendula isidingo. Ingxenye efanelekile yezinhlayiya ezinosayizi wezinhlayiyana ezihlukene iklanywe ngokwethiyori, futhi ixubene ne-fiber yensimbi kanye ne-ejenti yokunciphisa amanzi esebenza kahle kakhulu, inezici ezinhle kakhulu ezifana namandla acindezelayo aphezulu, ukuqina okuphezulu, ukuqina okuphezulu kokumelana nokushaqeka kanye nokuziphilisa okuqinile. ikhono lama-micro-cracks. Ukusebenza. Ucwaningo lobuchwepheshe bangaphandle ku-UHPC seluvuthiwe futhi selusetshenziswe kumaphrojekthi amaningi asebenzayo. Uma kuqhathaniswa namazwe angaphandle, ucwaningo lwasekhaya alujulile ngokwanele. U-Dong Jianmiao kanye nabanye bafunde ukufakwa kwefayibha ngokwengeza izinhlobo ezihlukene namanani emicu. Indlela yokuthonya kanye nomthetho wokhonkolo; U-Chen Jing et al. wafunda umthelela wobubanzi be-fiber yensimbi ekusebenzeni kwe-UHPC ngokukhetha imicu yensimbi enobubanzi obungu-4. I-UHPC inenani elincane kuphela lezicelo zobunjiniyela e-China, futhi isesigabeni socwaningo lwethiyori. Ukusebenza kwe-UHPC Superiority sekube ngenye yezinkomba zocwaningo zokuthuthukiswa okuphathekayo, kodwa kusenezinkinga eziningi okufanele zixazululwe. Njengezidingo eziphakeme zezinto ezingavuthiwe, izindleko eziphezulu, inqubo yokulungiselela eyinkimbinkimbi, njll., ekhawulela ukuthuthukiswa kobuchwepheshe bokukhiqiza be-UHPC. Phakathi kwazo, ukusebenzisa isitimu esinomfutho ophezulu Ukwelashwa kwe-UHPC ekushiseni okuphezulu kungayenza ithole izakhiwo eziphakeme zemishini nokuqina. Kodwa-ke, ngenxa yenqubo enzima yokuphulukisa isitimu kanye nezidingo eziphakeme zemishini yokukhiqiza, ukusetshenziswa kwezinto kungakhawulelwa kuphela kumayadi okwenziwa ngaphambili, futhi ukwakhiwa kwe-cast-in-place akukwazi ukwenziwa. Ngakho-ke, akufanelekile ukwamukela indlela yokwelapha okushisayo kumaphrojekthi wangempela, futhi kuyadingeka ukwenza ucwaningo olujulile mayelana nokushisa okujwayelekile kokuphulukisa i-UHPC.

Izinga lokushisa elijwayelekile elelapha i-UHPC isesigabeni socwaningo e-China, futhi isilinganiso sayo samanzi ukuya-ku-binder siphansi kakhulu, futhi sithambekele ekuphelelweni amanzi emzimbeni ngokushesha lapho kwakhiwa endaweni. Ukuze kuthuthukiswe ngokuphumelelayo isimo sokuphelelwa amanzi emzimbeni, izinto ezisekelwe kusimende ngokuvamile zengeza ama-thickeners athile okugcina amanzi entweni. I-ejenti yamakhemikhali yokuvimbela ukuhlukaniswa nokopha kwezinto, ithuthukise ukugcinwa kwamanzi nokuhlangana, ithuthukise ukusebenza komsebenzi wokwakha, futhi ithuthukise ngokuphumelelayo izakhiwo zemishini zezinto ezisekelwe kusimende. IHydroxypropyl methyl cellulose ether (HPMC) njenge-polymer Thickener, engasabalalisa ngempumelelo i-polymer gelled slurry nezinto zokwakha ezintweni ezisekelwe kusimende ngokulinganayo, futhi amanzi amahhala ku-slurry azoba amanzi abophekile, ukuze kungabi lula ukulahlekelwa kusuka. i-slurry futhi ithuthukise ukusebenza kokugcinwa kwamanzi kakhonkolo .Ukuze kwehliswe umthelela we-cellulose ether ku-fluidity ye-UHPC, i-low-viscosity cellulose ether yakhethelwa ukuhlolwa.

Kafushane, ukuze kuthuthukiswe ukusebenza komsebenzi wokwakha ngesisekelo sokuqinisekisa izakhiwo zemishini yokwelapha i-UHPC yezinga lokushisa elivamile, leli phepha lihlola umphumela wokuqukethwe kwe-low-viscosity cellulose ether ekwelapheni izinga lokushisa elivamile ngokusekelwe kumakhemikhali e-cellulose ether. kanye nendlela yayo yokwenza ku-UHPC slurry. Umthelela we-fluidity, isikhathi sokuhlangana, amandla acindezelayo, amandla e-flexural, amandla e-axial tensile kanye nevelu eqinile yokugcina ye-UHPC ukuze kunqunywe umthamo ofanele we-cellulose ether.

1. Uhlelo lokuhlola

1.1 Hlola i-raw materials ne-mix ratio

Izinto zokusetshenziswa zalokhu kuhlolwa yilezi:

1) Usimende: P·O 52.5 usimende ojwayelekile wasePortland okhiqizwa eLiuzhou.

2) Fly ash: Fly ash ekhiqizwa eLiuzhou.

3) Impushana ye-Slag: I-S95 eyi-granulated blast furnace powder ekhiqizwa e-Liuzhou.

4) I-silica fume: intuthu ye-silica ebethelwe kancane, impushana empunga, okuqukethwe kwe-SiO2≥92%, indawo ethize engama-23 m²/g.

5) Isihlabathi se-quartz: 20 ~ 40 mesh (0.833 ~ 0.350 mm).

I-6) Isinciphisi samanzi: isinciphisi samanzi se-polycarboxylate, impushana emhlophe, izinga lokunciphisa amanzi≥30%.

I-7) I-latex powder: i-latex powder ephinda ihlakazeka.

I-8) I-Fiber ether: i-hydroxypropyl methylcellulose METHOCEL ekhiqizwa e-United States, i-viscosity 400 MPa s.

I-9) I-fiber yensimbi: i-microwire steel fiber eqondile yethusi-plated, ububanziφ ingu-0.22 mm, ubude buyi-13 mm, amandla okuqina yi-2 000 MPa.

Ngemva kocwaningo oluningi lokuhlola ekuqaleni kwesigaba sokuqala, kunganqunywa ukuthi isilinganiso esiyisisekelo sengxube sokushisa okuvamile esiphulukisa ukhonkolo ophakeme kakhulu usimende: umlotha womlotha: impushana yamaminerali: intuthu yesilika: isihlabathi: i-ejenti yokunciphisa amanzi: impushana ye-latex: amanzi = 860: 42: 83: 110:980:11:2:210, okuqukethwe kwevolumu ye-fiber yensimbi yi-2%. Engeza 0, 0.25%, 0.50%, 0.75%, 1.00% HPMC ye-cellulose ether (HPMC) okuqukethwe kulesi silinganiso semiksi eyisisekelo Setha izivivinyo zokuqhathanisa ngokulandelanayo.

1.2 Indlela yokuhlola

Kala izinto ezingavuthiwe eziyimpushana eyomile ngokwesilinganiso sokuxutshwa bese uzibeka ku-HJW-60 shaft eyodwa enezingqimba ephoqwe ukuxuba ukhonkolo. Qala i-mixer kuze kube iyunifomu, engeza amanzi bese uxuba imizuzu engu-3, ​​cisha i-mixer, engeza i-fiber yensimbi enesisindo bese uqala kabusha umxube imizuzu emi-2. Yenzelwe i-UHPC slurry.

Izinto zokuhlola zifaka uketshezi, isikhathi sokusetha, amandla acindezelayo, amandla avumelana nezimo, amandla e-axial tensile kanye nevelu eqinile yokuqina. Ukuhlolwa kwe-fluidity kunqunywa ngokusho kwe-JC/T986-2018 “Cement-based Grouting Materials”. Ukuhlolwa kwesikhathi sokusetha kuhambisana ne-GB/T 1346-2011 "Ukusetshenziswa Kwamanzi Okungaguquguquki Kwesimende Okujwayelekile kanye Nokusetha Indlela Yokuhlola Isikhathi". Ukuhlolwa kwamandla okuguquguqukayo kunqunywa ngokuya nge-GB/T50081-2002 “Izindlela Ezijwayelekile Zokuhlola Zezakhiwo Zemishini Yokhonkolo Ovamile”. Ukuhlolwa kwamandla acindezelayo, amandla e-axial tensile kanye nokuhlolwa kwevelu eqinile yokugcina kunqunywa ngokuya nge-DLT5150-2001 “Imithetho Yokuhlola Ukhonkolo Wamanzi”.

2. Imiphumela yokuhlolwa

2.1 I-Liquidity

Imiphumela yokuhlolwa kwe-fluidity ibonisa umthelela wokuqukethwe kwe-HPMC ekulahlekelweni kwe-UHPC fluidity ngokuhamba kwesikhathi. Kuphawulwa esimeni sokuhlola ukuthi ngemva kokuba i-slurry ngaphandle kwe-ether ye-cellulose inyakaziswa ngokulinganayo, indawo engaphezulu ijwayele ukuphelelwa amanzi emzimbeni kanye noqweqwe, futhi i-fluidity ilahleka ngokushesha. , futhi ukusebenza kwawo kwawohloka. Ngemva kokwengeza i-cellulose ether, kwakungekho isikhumba ebusweni, ukulahlekelwa uketshezi ngokuhamba kwesikhathi kwaba kuncane, futhi ukusebenza kahle kwahlala kukuhle. Phakathi kwebanga lokuhlola, ukulahlekelwa okuncane kokuketshezi kwaba ngu-5 mm emizuzwini engama-60. Ukuhlaziywa kwedatha yokuhlola kubonisa ukuthi, Inani le-low-viscosity cellulose ether linethonya elincane ekuphumeni kokuqala kwe-UHPC, kodwa linomthelela omkhulu ekulahlekelweni kwe-fluidity ngokuhamba kwesikhathi. Uma ingekho i-cellulose ether engeziwe, ukulahlekelwa kwe-fluidity ye-UHPC ngu-15 mm; Ngokukhula kwe-HPMC, ukulahlekelwa kwe-fluidity kodaka kuncipha; lapho umthamo ungu-0.75%, ukulahlekelwa kwe-fluidity ye-UHPC kuncane kakhulu ngokuhamba kwesikhathi, okungu-5mm; ngemva kwalokho, ngokwanda kwe-HPMC, ukulahlekelwa kwe-fluidity ye-UHPC ngokuhamba kwesikhathi Cishe akushintshile.

NgemvaI-HPMCixubene ne-UHPC, ithinta izakhiwo ze-rheological ze-UHPC ezivela ezicini ezimbili: enye iwukuthi ama-bubbles amancane azimele alethwa enqubweni eshukumisayo, okwenza i-aggregate kanye nomlotha ondizayo kanye nezinye izinto zibe "umphumela webhola", okwandisa umphumela. ukusebenza Ngesikhathi esifanayo, inani elikhulu lezinto ezisikiwe lingakwazi ukugoqa i-aggregate, ukuze i-aggregate ikwazi "ukumiswa" ngokulinganayo ku-slurry, futhi ingakwazi ukuhamba ngokukhululekile, ukungqubuzana phakathi kwama-aggregates kuyancipha, futhi i-fluidity iyanda; okwesibili ukukhulisa i-UHPC Amandla ahlangene anciphisa uketshezi. Njengoba ukuhlolwa kusebenzisa i-HPMC ye-viscosity ephansi, isici sokuqala silingana nesici sesibili, futhi i-fluidity yokuqala ayishintshi kakhulu, kodwa ukulahlekelwa kwe-fluidity ngokuhamba kwesikhathi kungancishiswa. Ngokusho kokuhlaziywa kwemiphumela yokuhlolwa, kungaziwa ukuthi ukwengeza inani elifanele le-HPMC ku-UHPC kungathuthukisa kakhulu ukusebenza kokwakhiwa kwe-UHPC.

2.2 Ukusetha isikhathi

Kusuka kuthrendi yoshintsho lwesikhathi sokusetha se-UHPC ethintwa inani le-HPMC, kungabonwa ukuthi i-HPMC idlala indima ebambezelekayo ku-UHPC. Uma inani lilikhulu, umphumela wokuhlehlisa usobala kakhulu. Uma inani lingu-0.50%, isikhathi sokusetha se-mortar singama-55min. Uma kuqhathaniswa neqembu elilawulayo (imizuzu engu-40), likhuphuke ngo-37.5%, futhi ukunyuka kwakungakabi sobala. Lapho umthamo wawungu-1.00%, isikhathi sokusetha se-mortar sasiyi-100 min, okwakuyi-150% ephakeme kuneqembu lokulawula (i-40 min).

Izici zesakhiwo samangqamuzana e-cellulose ether zithinta umphumela wawo wokuhlehlisa. Isakhiwo esiyisisekelo samangqamuzana ku-cellulose ether, okungukuthi, isakhiwo sendandatho ye-anhydroglucose, singasabela nama-ion e-calcium ukwakha ama-molecule e-sugar-calcium, ukunciphisa isikhathi sokungeniswa kokusabela kwe-cement clinker hydration. I-Ca(OH)2, inciphisa ijubane lokusabela kukasimende, ngaleyo ndlela ibambezeleka ukumiswa kukasimende.

2.3 Amandla acindezelayo

Kusukela ebudlelwaneni phakathi kwamandla okucindezela amasampula e-UHPC ezinsukwini ezingu-7 nezinsuku ezingu-28 kanye nokuqukethwe kwe-HMPC, kungabonakala ngokucacile ukuthi ukungezwa kwe-HPMC kwandisa kancane kancane ukwehla kwamandla okucindezela we-UHPC. 0.25% HPMC, amandla okucindezela e-UHPC ehla kancane, futhi isilinganiso samandla acindezelayo singu-96%. Ukwengeza u-0.50% we-HPMC akunawo umthelela osobala esilinganisweni samandla acindezelayo we-UHPC. Qhubeka ungeze i-HPMC ngaphakathi kwendawo yokusebenzisa, i-UHPC's Amandla okucindezela ehle kakhulu. Lapho okuqukethwe kwe-HPMC kukhuphukela ku-1.00%, isilinganiso samandla acindezelayo sehla saya ku-66%, futhi ukuncipha kwamandla kwakubi kakhulu. Ngokusho kokuhlaziywa kwedatha, kufaneleka kakhulu ukwengeza i-0.50% HPMC, futhi ukulahlekelwa amandla okucindezela kuncane

I-HPMC inomphumela othile wokungenisa umoya. Ukwengezwa kwe-HPMC kuzodala inani elithile lamabhamuza amancane ku-UHPC, okuzonciphisa ukuminyana kwenqwaba ye-UHPC esanda kuxutshwa. Ngemuva kokuthi i-slurry iqinisiwe, i-porosity izokhula kancane kancane futhi ukubumbana kuzokwehla, ikakhulukazi okuqukethwe kwe-HPMC. Phezulu. Ukwengeza, ngokunyuka kwenani le-HPMC eyethulwe, kusekhona ama-polymers amaningi aguquguqukayo kuma-pores we-UHPC, angakwazi ukudlala indima ebalulekile ekuqineni okuhle nokusekela okucindezelayo lapho i-matrix ye-composite ye-cementitious icindezelwa. .Ngakho-ke, ukungezwa kwe-HPMC kunciphisa kakhulu amandla okucindezela e-UHPC.

2.4 Amandla e-flexible

Kusukela ebuhlotsheni phakathi kwamandla aguquguqukayo amasampula e-UHPC ezinsukwini ezingu-7 nezinsuku ze-28 kanye nokuqukethwe kwe-HMPC, kungabonakala ukuthi amajika okushintsha amandla aguquguqukayo namandla okucindezela afanayo, futhi ukuguqulwa kwamandla okuguquguqukayo phakathi kwe-0 no-0.50% ye-HMPC ayifani. Njengoba ukungezwa kwe-HPMC kuqhubeka, amandla okuguquguquka amasampula e-UHPC ehle kakhulu.

Umphumela we-HPMC emandleni aguquguqukayo we-UHPC ikakhulukazi ezicini ezintathu: i-cellulose ether inemiphumela yokuhlehlisa kanye ne-air-entraining, enciphisa amandla okuguquguquka kwe-UHPC; futhi isici sesithathu i-polymer eguquguqukayo ekhiqizwa i-cellulose ether, Ukunciphisa ukuqina kwesifanekiso kunciphisa ukwehla kwamandla okuguquguquka kwesifanekiso kancane. Ukuba khona kanyekanye kwalezi zici ezintathu kunciphisa amandla okucindezela wesampula ye-UHPC futhi kunciphisa amandla okuguquguquka.

2.5 Amandla e-axial tensile kanye nenani lokugcina eliqinile

Ubudlelwano phakathi kwamandla okuqinile wezibonelo ze-UHPC ku-7 d no-28 d nokuqukethwe kwe-HMPC. Ngokukhula kokuqukethwe kwe-HPMC, amandla aqinile wezibonelo ze-UHPC aqale ashintsha kancane abese ehla ngokushesha. Ijika lamandla e-tensile libonisa ukuthi uma okuqukethwe kwe-HPMC kusifanekiso kufinyelela ku-0.50%, inani lamandla e-axial tensile yesifanekiso se-UHPC ngu-12.2MPa, kanti isilinganiso samandla e-tensile singu-103%. Ngokukhuphuka okwengeziwe kokuqukethwe kwe-HPMC kwesifanekiso, i-axial Inani lamandla e-central tensile laqala ukwehla kakhulu. Lapho okuqukethwe kwe-HPMC kwesampula kungu-0.75% kanye no-1.00%, izilinganiso zamandla e-tensile zazingu-94% no-78%, ngokulandelana, ezazingaphansi kwamandla e-axial tensile we-UHPC ngaphandle kwe-HPMC.

Kusukela ebudlelwaneni phakathi kwamanani okuqina okugcina amasampula e-UHPC ezinsukwini eziyi-7 nezinsuku ezingama-28 kanye nokuqukethwe kwe-HMPC, kungabonakala ukuthi amanani okugcina e-tensile cishe awashintshile ngokunyuka kwe-cellulose ether ekuqaleni, nalapho okuqukethwe i-cellulose ether ifinyelela ku-0.50 % bese iqala ukwehla ngokushesha.

Umthelela yenani elingeziwe le-HPMC kumandla we-axial tensile kanye nevelu eqinile yokuqina yamasampula e-UHPC abonisa inkambiso yokugcina ingashintshile bese yehla. Isizathu esiyinhloko ukuthi i-HPMC ingakhiwa ngokuqondile phakathi kwezinhlayiya zikasimende ezi-hydrated Ingqimba yefilimu yokuvala i-polymer engangeni manzi idlala indima yokubekwa uphawu, ukuze inani elithile lamanzi ligcinwe ku-UHPC, elihlinzeka ngamanzi adingekayo ukuze kuthuthukiswe ukuqhubeka kwe-hydration eyengeziwe. kasimende, ngaleyo ndlela kuthuthukiswe amandla usimende. Ukwengezwa kwe-HPMC kuthuthukisa Ukubumbana kwe-UHPC kunikeza i-slurry ngokuguquguquka, okwenza i-UHPC ivumelane ngokugcwele nokuncipha nokuguqulwa kwezinto eziyisisekelo, futhi ithuthukisa kancane amandla e-UHPC. Kodwa-ke, lapho okuqukethwe kwe-HPMC kudlula inani elibalulekile, umoya ofakiwe uthinta amandla esifanekiso. Imiphumela emibi kancane kancane yadlala indima eholayo, futhi amandla e-axial tensile kanye nevelu eqinile yokugcina yesifanekiso yaqala ukwehla.

3. Isiphetho

I-1) I-HPMC ingathuthukisa kakhulu ukusebenza kokusebenza kwezinga lokushisa elijwayelekile elelapha i-UHPC, inwebe isikhathi sayo sokuhlangana futhi yehlise ukulahleka kwe-fluidity ye-UHPC esanda kuxutshwa ngokuhamba kwesikhathi.

2) Ukwengezwa kwe-HPMC kwethula inani elithile lamabhamuza amancane phakathi nenqubo enyakazayo yodaka. Uma inani likhulu kakhulu, amabhamuza azoqoqana kakhulu futhi akhe amabhamuza amakhulu. I-slurry ihlangene kakhulu, futhi amabhamuza awakwazi ukuchichima futhi aqhume. Izimbotshana ze-UHPC eziqinile ziyancipha; ngaphezu kwalokho, i-polymer eguquguqukayo ekhiqizwa yi-HPMC ayikwazi ukuhlinzeka ngokusekela okuqinile uma ingaphansi kwengcindezi, futhi amandla okucindezela nokuguquguquka ayancipha kakhulu.

3) Ukwengezwa kwe-HPMC kwenza ipulasitiki ye-UHPC futhi ibe nezimo. Amandla e-axial tensile kanye nenani lokugcina eliqinile lezibonelo ze-UHPC akulula ukushintsha ngokwanda kokuqukethwe kwe-HPMC, kodwa lapho okuqukethwe kwe-HPMC kweqa inani elithile, Amandla e-axial tensile kanye namanani okugcina e-tensile ancipha kakhulu.

4) Lapho ulungiselela izinga lokushisa elivamile elelapha i-UHPC, umthamo we-HPMC kufanele ulawulwe ngokuqinile. Uma umthamo ungu-0.50%, ubudlelwano phakathi kokusebenza kokusebenza kanye nezakhiwo zemishini ze-UHPC evamile yokwelapha izinga lokushisa bungaxhunyaniswa kahle.