I-Methyl cellulose ether kwiqondo lobushushu begumbi elinyanga ikonkrithi yokusebenza okuphezulu kakhulu

Inkcazo: Ngokutshintsha umxholo we-hydroxypropyl methylcellulose ether (HPMC) kwiqondo lokushisa eliqhelekileyo lokunyanga ikhonkrithi ye-ultra-high performance (UHPC), umphumo we-cellulose ether kwi-fluidity, ixesha lokubeka, amandla okunyamezela, kunye namandla okuguquguquka kwe-UHPC yafundwa. , amandla e-axial tensile kunye nexabiso lokugqibela, kwaye iziphumo zahlalutya. Iziphumo zovavanyo zibonisa ukuba: ukongeza akukho ngaphezu kwe-1.00% ye-viscosity ephantsi ye-HPMC ayichaphazeli ubuninzi be-UHPC, kodwa kunciphisa ilahleko ye-fluidity ngokuhamba kwexesha. , kunye nokwandisa ixesha lokumisela, ukuphucula kakhulu umsebenzi wokwakha; xa umxholo ungaphantsi kwe-0.50%, impembelelo kumandla oxinzelelo, amandla e-flexural kunye namandla e-axial tensile ayibalulekanga, kwaye emva kokuba umxholo ungaphezulu kwe-0.50%, umatshini wayo Ukusebenza kuncitshiswe ngaphezu kwe-1/3. Ukuqwalasela iindlela ezahlukeneyo zentsebenzo, idosi ecetyiswayo ye-HPMC yi-0.50%.

Amagama angundoqo: ikhonkrithi yokusebenza ephezulu kakhulu; i-cellulose ether; ukunyanga ubushushu obuqhelekileyo; amandla oxinzelelo; amandla okuguquguquka; tensile strength

0,Intshayelelo

Ngophuhliso olukhawulezayo lweshishini lokwakha laseTshayina, iimfuno zentsebenzo ebambekayo kubunjineli bokwenyani nazo ziye zanda, kwaye ikhonkrithi yokusebenza ephezulu kakhulu (UHPC) iveliswe ukuphendula imfuno. Elona nqanaba lilungileyo lamasuntswana anobungakanani bamasuntswana ahlukeneyo ayilwe ngokwethiyori, kwaye axutywe nefiber yentsimbi kunye nearhente yokunciphisa amanzi asebenza ngokufanelekileyo, ineepropathi ezigqwesileyo ezinje ngokuqina okuphezulu okuphezulu, ukuqina okuphezulu, ukomelela okuphezulu kokuxhathisa kunye nokuziphilisa okunamandla. ukukwazi kwee-micro-cracks. Ukusebenza. Uphando lweteknoloji yangaphandle kwi-UHPC ikhulile kwaye isetyenziswe kwiiprojekthi ezininzi eziphathekayo. Xa kuthelekiswa namazwe angaphandle, uphando lwasekhaya alunzulu ngokwaneleyo. U-Dong Jianmiao kunye nabanye bafunde ukubandakanywa kwefayibha ngokongeza iintlobo ezahlukeneyo kunye nezixa zefiber. Indlela yempembelelo kunye nomthetho wekhonkrithi; UChen Jing et al. wafunda impembelelo ye-fiber fiber diameter ekusebenzeni kwe-UHPC ngokukhetha imicu yetsimbi ene-4 diameters. I-UHPC inenani elincinane kuphela lezicelo zobunjineli e-China, kwaye isekho kwinqanaba lophando lwethiyori. Ukusebenza kwe-UHPC Superiority ibe yenye yezalathiso zophando zophuhliso lwekhonkrithi, kodwa kusekho iingxaki ezininzi ekufuneka zisonjululwe. Njengeemfuno eziphezulu zezinto eziluhlaza, ixabiso eliphezulu, inkqubo yokulungiselela enzima, njl., ukukhawulela uphuhliso lweteknoloji yokuvelisa i-UHPC. Phakathi kwabo, ukusebenzisa umphunga woxinzelelo oluphezulu Ukunyangwa kwe-UHPC kwiqondo lokushisa eliphezulu kunokuyenza ifumane iipropati eziphezulu zoomatshini kunye nokuqina. Nangona kunjalo, ngenxa yenkqubo yokunyangwa kwe-steam enzima kunye neemfuno eziphezulu zezixhobo zokuvelisa, ukusetyenziswa kwezinto eziphathekayo kunokukhawulelwa kuphela kwiiyadi ze-prefabrication, kwaye ukwakhiwa kwe-cast-in-place akunakwenziwa. Ngoko ke, akufanelekanga ukwamkela indlela yokunyanga i-thermal kwiiprojekthi zangempela, kwaye kuyimfuneko ukwenza uphando olunzulu malunga nokushisa okuqhelekileyo kokunyanga i-UHPC.

Ubushushu obuqhelekileyo bokunyanga i-UHPC ikwinqanaba lophando eTshayina, kwaye umlinganiselo wayo wamanzi ukuya kwi-binder uphantsi kakhulu, kwaye uthambekele ekuphelelweni kwamanzi ngokukhawuleza phezu komhlaba ngexesha lokwakhiwa kwendawo. Ukuze kuphuculwe ngokufanelekileyo i-phenomenon dehydration, izinto ezisekelwe kwi-samente zihlala zongeza ezinye ii-thickeners zokugcina amanzi kwizinto eziphathekayo. I-agent ye-Chemical ukuthintela ulwahlulo kunye nokopha kwezixhobo, ukwandisa ukugcinwa kwamanzi kunye nokubambisana, ukuphucula ukusebenza kolwakhiwo, kunye nokuphucula ngokufanelekileyo iimpawu zemishini yezinto ezisekelwe kwi-samente. I-Hydroxypropyl methyl cellulose ether (HPMC) njenge-polymer Thickener, enokusasaza ngokufanelekileyo i-polymer gelled slurry kunye nemathiriyeli kwizinto ezisekelwe kwisamente ngokulinganayo, kunye namanzi akhululekile kwi-slurry aya kuba ngamanzi abophekileyo, ukuze angabi lula ukulahlekelwa ukusuka. i-slurry kunye nokuphucula ukugcinwa kwamanzi kwikhonkrithi .Ukuze kuncitshiswe impembelelo ye-cellulose ether kwi-fluidity ye-UHPC, i-low-viscosity cellulose ether yakhethwa kuvavanyo.

Isishwankathelo, ukwenzela ukuba kuphuculwe ukusebenza kolwakhiwo ngesiseko sokuqinisekisa iipropathi zemishini ye-UHPC yobushushu obuqhelekileyo bokunyanga, eli phepha lifunda umphumo we-low-viscosity cellulose ether content on the normal-temperature healing based on the chemical properties of cellulose ether. kunye nendlela yokusebenza kwi-UHPC slurry. Impembelelo ye-fluidity, ixesha lokudibanisa, amandla oxinzelelo, amandla okuguquguquka, amandla e-axial tensile kunye nexabiso lokugqibela le-UHPC ukumisela idosi efanelekileyo ye-cellulose ether.

1. Isicwangciso sovavanyo

1.1 Vavanya imathiriyeli ekrwada kunye nomlinganiselo womxube

Iimathiriyeli ekrwada kolu vavanyo zezi:

1) Isamente: P·O 52.5 isamente eqhelekileyo yasePortland eveliswe eLiuzhou.

2) Fly ash: Bhabha uthuthu oluveliswe eLiuzhou.

3) I-Slag powder: I-S95 i-granulated blast furnace powder eyenziwe e-Liuzhou.

4) Umsi weSilica: umsi wesilica ofihliweyo osikelwe kancinci, umgubo ongwevu, umxholo weSiO2≥I-92%, indawo ethile ye-23 m²/g.

5) Isanti ye-quartz: 20 ~ 40 mesh (0.833 ~ 0.350 mm).

I-6) Isinciphisi samanzi: i-polycarboxylate yokunciphisa amanzi, umgubo omhlophe, izinga lokunciphisa amanzi≥30%.

I-7) I-Latex powder: i-latex powder ehlanjululwayo.

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

I-9) I-fiber yensimbi: i-fiber yensimbi ye-copper-plated i-microwire, ububanziφ yi-0.22 mm, ubude yi-13 mm, amandla e-tensile yi-2 000 MPa.

Emva kophando oluninzi lovavanyo kwinqanaba lokuqala, kunokuqinisekiswa ukuba umlinganiselo osisiseko wokuxuba ubushushu obuqhelekileyo obunyanga i-concrete ye-ultra-high yisamente: umlotha we-fly: umgubo wamaminerali: umsi we-silica: isanti: i-arhente yokunciphisa amanzi: i-latex powder: amanzi = 860: 42: 83: 110:980:11:2:210, umxholo we-fiber yensimbi yi-2%. Yongeza i-0, 0.25%, 0.50%, 0.75%, 1.00% HPMC ye-cellulose ether (HPMC) umxholo kulo mlinganiso wokuxuba osisiseko Setha imifuniselo yokuthelekisa ngokulandelelana.

1.2 Indlela yokuvavanya

Yenza umlinganiselo wemathiriyeli eyomileyo yomgubo ekrwada ngokomlinganiselo wokuxuba kwaye uzibeke kwi-HJW-60 enye ethe tyaba yeshafti enyanzelweyo yokuhlanganisa ikhonkrithi. Qala umxube kude kube yiyunifomu, yongeza amanzi kwaye udibanise imizuzu emi-3, cima umxube, yongeza i-fiber yensimbi enobunzima kwaye uqalise kwakhona umxube wemizuzu emi-2. Yenziwe ibe ludaka lwe-UHPC.

Izinto zovavanyo ziquka ubumanzi, ixesha lokumisela, amandla acinezelayo, amandla okuguquguquka, amandla e-axial tensile kunye nexabiso lokugqibela. Uvavanyo lwe-fluidity lumiselwa ngokwe-JC/T986-2018 “Cement-based Grouting Materials”. Uvavanyo lwexesha lokumisela luhambelana ne-GB / T 1346-I-2011 "I-Cement Standard Consistency Consistency Water Use and Setting Time Test Method". Uvavanyo lwamandla oluguquguqukayo lumiselwa ngokwe-GB/T50081-2002 "Iindlela eziMgangatho zoVavanyo lweePropati zeMechanical zeConcrete eqhelekileyo". Uvavanyo lwamandla olucinezelayo, amandla e-axial tensile kunye Uvavanyo lwexabiso lokugqibela luchongwa ngokwe-DLT5150-2001 "Imigaqo yoVavanyo lwe-Hydraulic Concrete".

2. Iziphumo zovavanyo

2.1 Ubungakanani bemali

Iziphumo zovavanyo lwe-fluidity zibonisa impembelelo yomxholo we-HPMC ekulahlekeni kwe-UHPC fluidity ngokuhamba kwexesha. Kuphawulwa kwimeko yokuvavanya ukuba emva kokuba i-slurry ngaphandle kwe-ether ye-cellulose ixutywe ngokulinganayo, ubuso buxhomekeke ekuphelelweni kwamanzi kunye ne-crusting, kwaye i-fluidity ilahlekile ngokukhawuleza. , kunye nokusebenza kakubi. Emva kokongeza i-cellulose ether, kwakungekho sikhumba ebusweni, ukulahlekelwa kwamanzi ngokuhamba kwexesha kwakuncinci, kwaye ukusebenza kakuhle kwahlala kulungile. Ngaphakathi koluhlu lovavanyo, ilahleko encinci ye-fluidity yayiyi-5 mm kwimizuzu engama-60. Uhlalutyo lwedatha yovavanyo lubonisa ukuba, Ubungakanani be-ether ye-cellulose ephantsi ye-viscosity inempembelelo encinci kwi-fluidity yokuqala ye-UHPC, kodwa inempembelelo enkulu ekulahlekeni kwe-fluidity ngokuhamba kwexesha. Xa kungekho ether ye-cellulose eyongeziweyo, ukulahleka kwe-fluidity ye-UHPC yi-15 mm; Ngokunyuka kwe-HPMC, ilahleko ye-fluidity yodaka iyancipha; xa i-dosage yi-0.75%, ilahleko ye-fluidity ye-UHPC yinto encinci kunye nexesha, eliyi-5mm; emva koko, kunye nokwanda HPMC, ilahleko fluidity UHPC kunye nexesha Phantse ingatshintshanga.

Emva kokoHPMCixutywe ne-UHPC, ichaphazela iimpawu ze-rheological ze-UHPC kwimiba emibini: enye kukuba amaqamza amancinci azimeleyo aziswa kwinkqubo yokuvuselela, eyenza i-aggregate kunye ne-fly ash kunye nezinye izinto zenza "impembelelo yebhola", eyandisa Ukusetyenzwa Kwangaxeshanye, ubuninzi bezinto ze-cementitious ziyakwazi ukugubungela i-aggregate, ukwenzela ukuba i-aggregate ikwazi "ukunqunyanyiswa" ngokulinganayo kwi-slurry, kwaye ikwazi ukuhamba ngokukhululekile, ukungqubuzana phakathi kwee-aggregates kuyancipha, kwaye i-fluidity iyanda; okwesibini kukunyusa i-UHPC Amandla adibeneyo anciphisa umbane. Ekubeni uvavanyo lusebenzisa i-HPMC ye-viscosity ephantsi, inkalo yokuqala ilingana nenkalo yesibini, kwaye i-fluidity yokuqala ayitshintshi kakhulu, kodwa ukulahlekelwa kwe-fluidity ngokuhamba kwexesha kunokuncitshiswa. Ngokohlalutyo lweziphumo zovavanyo, kuyaziwa ukuba ukongeza inani elifanelekileyo le-HPMC kwi-UHPC kunokuphucula kakhulu ukusebenza kokwakhiwa kwe-UHPC.

2.2 Ukumisela ixesha

Ukususela kwindlela yokutshintsha kwexesha lokumisela i-UHPC echaphazelekayo yimali ye-HPMC, kunokubonwa ukuba i-HPMC idlala indima ebambezelayo kwi-UHPC. Okukhona isixa-mali sisikhulu, kokukhona kubonakala ngakumbi umphumo wokulibazisa. Xa inani liyi-0.50%, ixesha lokumisela lomdaka ngu-55min. Xa kuthelekiswa neqela lokulawula (i-40 min), linyuke nge-37.5%, kwaye ukunyuka kwakungabonakali. Xa i-dosage yayiyi-1.00%, ixesha lokumisela lomdaka laliyi-100 min, eyayiyi-150% ephezulu kuneqela lokulawula (i-40 min).

Iimpawu zesakhiwo semolekyuli ye-ether ye-cellulose ichaphazela umphumo wayo wokulibazisa. Isakhiwo esisisiseko semolekyuli kwi-cellulose ether, oko kukuthi, i-anhydroglucose ring structure, inokusabela kunye ne-calcium ions ukwenza i-sugar-calcium i-molecular compounds, ukunciphisa ixesha lokungeniswa kwe-cement clinker hydration reaction. I-Ca (OH) 2, ukunciphisa isantya se-cement hydration reaction, ngaloo ndlela ilibazisa ukusetwa kwesamente.

2.3 Amandla acinezelayo

Ukususela kubudlelwane phakathi kwamandla oxinzelelo lweesampulu ze-UHPC kwiintsuku ze-7 kunye neentsuku ze-28 kunye nomxholo we-HMPC, kunokubonwa ngokucacileyo ukuba ukongezwa kwe-HPMC kwandisa ngokuthe ngcembe ukuhla kwamandla oxinzelelo lwe-UHPC. I-0.25% ye-HPMC, amandla oxinzelelo lwe-UHPC ayancipha kancane, kwaye umlinganiselo wamandla ocinezelayo yi-96%. Ukongeza i-0.50% ye-HPMC ayinayo impembelelo ecacileyo kumlinganiselo wamandla oxinzelelo lwe-UHPC. Qhubeka ukongeza i-HPMC ngaphakathi kwendawo yokusetyenziswa, UHPC's Amandla oxinzelelo ehle kakhulu. Xa umxholo we-HPMC unyuke ukuya kwi-1.00%, umlinganiselo wamandla ocinezelayo wehla ukuya kwi-66%, kwaye ukulahlekelwa kwamandla kwakunzulu. Ngokutsho kohlalutyo lwedatha, kulungele ngakumbi ukongeza i-0.50% ye-HPMC, kwaye ukulahlekelwa kwamandla oxinzelelo kuncinci.

I-HPMC inefuthe elithile lokungenisa umoya. Ukongezwa kwe-HPMC kuya kubangela inani elithile le-microbubbles kwi-UHPC, eya kunciphisa ubuninzi be-UHPC esanda kuxutywa. Emva kokuba i-slurry iqinisiwe, i-porosity iya kwanda ngokuthe ngcembe kwaye ukubumbana kuya kuncipha, ngakumbi umxholo we-HPMC. Phezulu. Ukongezelela, ngokunyuka kwexabiso le-HPMC elifakwe, kusekho iipolymers ezininzi eziguquguqukayo kwiipores ze-UHPC, ezingenako ukudlala indima ebalulekileyo ekuqineni okulungileyo kunye nenkxaso yoxinzelelo xa i-matrix ye-cementitious composite ixinzelelwe. .Ngoko ke, ukongezwa kwe-HPMC kunciphisa kakhulu amandla oxinzelelo lwe-UHPC.

2.4 Amandla e-Flexural

Ukususela kubudlelwane phakathi kwamandla e-flexural eesampuli ze-UHPC kwiintsuku ze-7 kunye neentsuku ze-28 kunye nomxholo we-HMPC, kunokubonwa ukuba iinguqu zenguqu zamandla aguquguqukayo kunye namandla oxinzelelo zifana, kunye nokutshintsha kwamandla okuguquguqukayo phakathi kwe-0 kunye ne-0.50% ye-HMPC ayifani. Njengoko ukongezwa kwe-HPMC kwaqhubeka, amandla okuguquguquka kweesampuli ze-UHPC zehla kakhulu.

Umphumo we-HPMC kumandla we-flexural ye-UHPC ikakhulu kwiinkalo ezintathu: i-cellulose ether ine-retarding kunye ne-air-entraining effects, ezinciphisa amandla e-flexural ye-UHPC; kwaye inkalo yesithathu yi-polymer eguquguqukayo eveliswa yi-cellulose ether, Ukunciphisa ukuqina komzekelo kunciphisa ukuhla kwamandla okuguquguquka kwe-specimen kancinane. Ubukho bexeshanye kwezi nkalo zintathu kunciphisa amandla oxinzelelo omfanekiso we-UHPC kwaye kunciphisa amandla okuguquguquka.

2.5 Amandla e-axial tensile kunye nexabiso lokugqibela

Ubudlelwane phakathi kokuqina kokuqina kweesampulu ze-UHPC kwi-7 d kunye ne-28 d kunye nomxholo we-HMPC. Ngokunyuka komxholo we-HPMC, amandla okuqina eesampulu ze-UHPC aqale atshintsha kancinci kwaye emva koko ehla ngokukhawuleza. Ijika lamandla e-tensile libonisa ukuba xa umxholo we-HPMC kwi-specimen ufikelela kwi-0.50%, ixabiso le-axial tensile yamandla e-UHPC ye-specimen yi-12.2MPa, kwaye umlinganiselo wamandla we-tensile yi-103%. Ngokunyuka okungaphezulu komxholo we-HPMC we-specimen, i-axial Ixabiso lamandla e-central tensile laqala ukuhla ngokukhawuleza. Xa umxholo we-HPMC we-specimen wawuyi-0.75% kunye ne-1.00%, imilinganiselo yamandla e-tensile yayiyi-94% kunye ne-78%, ngokulandelanayo, eyayingaphantsi kwe-axial tensile yamandla ye-UHPC ngaphandle kwe-HPMC.

Ukususela kubudlelwane phakathi kwamaxabiso e-tensile yokugqibela yeesampulu ze-UHPC kwiintsuku ze-7 kunye neentsuku ze-28 kunye nomxholo we-HMPC, kunokubonwa ukuba amaxabiso e-tensile ekugqibeleni aphantse angatshintshi ngokunyuka kwe-cellulose ether ekuqaleni, kwaye xa umxholo I-cellulose ether ifikelela kwi-0.50% kwaye yaqala ukuhla ngokukhawuleza.

Isiphumo semali eyongeziweyo ye-HPMC kumandla e-axial tensile kunye nexabiso lokugqibela le-UHPC yesampulu ibonisa umkhwa wokugcina phantse ungatshintshanga kwaye wehla. Esona sizathu siphambili kukuba i-HPMC inokwakheka ngokuthe ngqo phakathi kwamaqhekeza e-samente e-hydrated Umaleko wefilimu yokutywinwa ye-polymer engenamanzi idlala indima yokutywinwa, ukuze umlinganiselo othile wamanzi ugcinwe kwi-UHPC, ebonelela ngamanzi ayimfuneko kuphuhliso oluqhubekayo lokuqhubela phambili kokuhamba kwamanzi. yesamente, ngaloo ndlela iphucula amandla esamente. Ukongezwa kwe-HPMC kuphucula Ukubambisana kwe-UHPC kunika i-slurry kunye nokuguquguquka, okwenza i-UHPC ilungelelanise ngokupheleleyo kwi-shrinkage kunye nokuguqulwa kwezinto ezisisiseko, kunye nokuphucula kancinci amandla e-UHPC. Nangona kunjalo, xa umxholo we-HPMC udlula ixabiso elibalulekileyo, umoya odibeneyo uchaphazela amandla omzekelo. Iziphumo ezibi ngokuthe ngcembe zidlale indima ephambili, kwaye amandla e-axial tensile kunye nexabiso lokugqibela le-specimen laqala ukwehla.

3. Isiphelo

I-1) I-HPMC inokuphucula kakhulu ukusebenza kweqondo lokushisa eliqhelekileyo lokunyanga i-UHPC, yandise ixesha layo lokudibanisa kunye nokunciphisa ukulahlekelwa kwe-fluidity ye-UHPC esanda kuxutywa ngokuhamba kwexesha.

2) Ukongezwa kwe-HPMC kwazisa inani elithile lamaqamza amancinci ngexesha lenkqubo yokuvuselela i-slurry. Ukuba inani likhulu kakhulu, amaqamza aya kubuthana kakhulu kwaye enze amaqamza amakhulu. I-slurry idibene kakhulu, kwaye amaqamza akakwazi ukuphuphuma kwaye agqabhuke. Iipores ze-UHPC ezilukhuni ziyancipha; ukongeza, i-polymer eguquguqukayo eveliswa yi-HPMC ayikwazi ukubonelela ngenkxaso eqinile xa iphantsi koxinzelelo, kwaye amandla oxinzelelo kunye nokuguquguquka ayancipha kakhulu.

3) Ukongezwa kwe-HPMC kwenza iplastiki ye-UHPC kwaye iguquguquke. Amandla e-axial tensile kunye nexabiso lokugqibela le-UHPC iisampulu aziguquki ngokunyuka komxholo we-HPMC, kodwa xa umxholo we-HPMC udlula ixabiso elithile, Amandla e-axial tensile kunye nemilinganiselo yokugqibela ye-tensile iyancipha kakhulu.

4) Xa ulungiselela ubushushu obuqhelekileyo bokunyanga i-UHPC, idosi ye-HPMC kufuneka ilawulwe ngokungqongqo. Xa i-dosage yi-0.50%, ubudlelwane phakathi kokusebenza komsebenzi kunye neempawu zemishini yokushisa okuqhelekileyo kokunyanga i-UHPC inokulungelelaniswa kakuhle.