Methyl cellulose ether ka mocheso oa kamore e phekolang konkreite ea ts'ebetso e phahameng haholo

Kakaretso: Ka ho fetola dikahare tsa hydroxypropyl methylcellulose ether (HPMC) ka mocheso o tloaelehileng oa ho phekola konkreite ea ultra-high performance (UHPC), phello ea cellulose ether holim'a metsi, ho beha nako, matla a khatello, le matla a flexural a UHPC a ithutoang. , matla a axial tensile le boleng ba ho qetela bo tsitsitseng, 'me liphello li ile tsa hlahlojoa. Liphetho tsa liteko li bontša hore: ho eketsa ha ho 1.00% ea HPMC e tlaase-viscosity ha e ame ho phalla ha UHPC, empa ho fokotsa tahlehelo ea metsi ka nako. , le ho lelefatsa nako ea ho beha, ho ntlafatsa haholo mosebetsi oa kaho; ha litaba li le ka tlase ho 0.50%, phello ea matla a khatello, matla a flexural le matla a axial tensile ha a bohlokoa, 'me hang ha litaba li feta 0.50%, mochine oa eona Ts'ebetso e fokotsehile ho feta 1/3. Ha ho nahanoa ka litšoantšiso tse fapaneng, tekanyetso e khothaletsoang ea HPMC ke 0.50%.

Mantsoe a bohlokoa: konkreite ea ts'ebetso e phahameng haholo; cellulose ether; phekolo e tloaelehileng ea mocheso; matla a hatellang; matla a flexural; matla a tšepe

0,Selelekela

Ka nts'etsopele e potlakileng ea indasteri ea kaho ea China, litlhoko tsa ts'ebetso ea konkreite ho boenjiniere ba 'nete le tsona li eketsehile,' me konkreite ea ts'ebetso e phahameng haholo (UHPC) e hlahisitsoe ho latela tlhoko. Karolo e nepahetseng ea likaroloana tse nang le boholo bo fapaneng ba likaroloana li entsoe ka maikutlo, 'me li kopantsoe le fiber ea tšepe le sesebelisoa se fokotsang metsi se sebetsang hantle haholo, se na le thepa e ntle joalo ka matla a phahameng a khatello, ho tiea ho hoholo, ho tšoarella ho matla ho ts'oenyeha le ho ipholisa ka matla. bokhoni ba micro-cracks. Tshebetso. Patlisiso ea mahlale a kantle ho naha ho UHPC e batla e holile ebile e sebelisitsoe mererong e mengata e sebetsang. Ha li bapisoa le linaha tse ling, lipatlisiso tsa lehae ha lia teba ka ho lekaneng. Dong Jianmiao le ba bang ba ithutile ho kenyelletsoa ha fiber ka ho eketsa mefuta e fapaneng ea likhoele. Mokhoa oa tšusumetso le molao oa konkreite; Chen Jing et al. o ithutile tšusumetso ea bophara ba fiber ea tšepe ts'ebetsong ea UHPC ka ho khetha likhoele tsa tšepe tse nang le li-diameter tse 4. UHPC e na le palo e nyane feela ea likopo tsa boenjineri naheng ea China, 'me e ntse e le sethaleng sa lipatlisiso tsa theory. Ts'ebetso ea UHPC Superiority e fetohile e 'ngoe ea litaelo tsa lipatlisiso tsa nts'etsopele ea konkreite, empa ho ntse ho na le mathata a mangata a lokelang ho rarolloa. Tse kang litlhoko tse phahameng tsa lisebelisoa tse tala, litšenyehelo tse phahameng, mokhoa o rarahaneng oa ho lokisetsa, joalo-joalo, ho thibela nts'etsopele ea theknoloji ea tlhahiso ea UHPC. Har'a bona, ho sebelisa mouoane o nang le khatello e phahameng Ho phekoloa ha UHPC ka mocheso o phahameng ho ka etsa hore e fumane thepa e phahameng ea mochine le ho tšoarella. Leha ho le joalo, ka lebaka la ts'ebetso e boima ea ho folisa mouoane le litlhoko tse phahameng tsa lisebelisoa tsa tlhahiso, ts'ebeliso ea thepa e ka lekanyetsoa feela ho li-yadi tsa prefabrication, 'me kaho ea sebaka sa marang-rang e ke ke ea etsoa. Ka hona, ha hoa lokela ho amohela mokhoa oa ho phekola ka mocheso mererong ea sebele, 'me hoa hlokahala ho etsa lipatlisiso tse tebileng ka mocheso o tloaelehileng oa ho phekola UHPC.

Mocheso o tloaelehileng oa pheko ea UHPC e sethaleng sa lipatlisiso Chaena, 'me tekanyo ea eona ea metsi-to-binder e tlase haholo,' me e na le tšekamelo ea ho felloa ke metsi ka potlako holim'a metsi nakong ea kaho ea setšeng. E le ho ntlafatsa ka katleho ts'ebetso ea ho felloa ke metsi 'meleng, lisebelisoa tse thehiloeng samente hangata li eketsa lisebelisoa tse ling tse bolokang metsi ho thepa. Moemeli oa lik'hemik'hale ho thibela karohano le ho tsoa mali ha thepa, ho ntlafatsa ho boloka metsi le momahano, ho ntlafatsa ts'ebetso ea kaho, le ho ntlafatsa ka katleho thepa ea mochini ea thepa e thehiloeng ho samente. Hydroxypropyl methyl cellulose ether (HPMC) e le polymer Thickener, e ka khonang ho aba slurry ea polymer gelled slurry le lisebelisoa ka thepa ea samente e thehiloeng ka mokhoa o lekanang, 'me metsi a sa lefelloeng a slurry a tla fetoha metsi a tlamiloeng, e le hore ho se ke ha e-ba bonolo ho lahleheloa ke metsi. slurry le ho ntlafatsa ts'ebetso ea ho boloka metsi ea konkreite .E le ho fokotsa tšusumetso ea cellulose ether ho fluidity ea UHPC, ether ea cellulose ether e tlaase e ile ea khethoa bakeng sa tlhahlobo.

Ka kakaretso, molemong oa ho ntlafatsa ts'ebetso ea kaho motheong oa ho netefatsa thepa ea mochini ea mocheso o tloaelehileng oa UHPC, pampiri ena e ithuta phello ea litaba tsa "low-viscosity cellulose ether" ho folisa mocheso o tloaelehileng o thehiloeng ho lik'hemik'hale tsa cellulose ether. le mokhoa oa eona oa ts'ebetso ho UHPC slurry. Tšusumetso ea mokelikeli, nako ea ho kopanya, matla a khatello, matla a flexural, axial tensile matla le boleng ba ho qetela ba UHPC ho fumana tekanyo e nepahetseng ea cellulose ether.

1. Morero oa teko

1.1 Leka lisebelisoa tse tala le karolelano ea motsoako

Lisebelisoa tsa tlhahlobo ena ke:

1) Samente: P·O 52.5 samente e tloaelehileng ea Portland e hlahisoang Liuzhou.

2) Fly ash: Fly molora o hlahisoang Liuzhou.

3) Phofo ea Slag: S95 granulated blast furnace slag phofo e hlahisoang Liuzhou.

4) Mosi oa silika: mosi oa silika o kentsoeng ka thata, phofo e bohlooho, litaba tsa SiO2≥92%, sebaka se khethehileng sa 23 m²/g.

5) Lehlabathe la quartz: 20 ~ 40 mesh (0.833 ~ 0.350 mm).

6) Sesebelisoa sa metsi: se fokotsang metsi a polycarboxylate, phofo e tšoeu, sekhahla sa ho fokotsa metsi≥30%.

7) Latex phofo: redispersible latex phofo.

8) Fiber ether: hydroxypropyl methylcellulose METHOCEL e hlahisoang United States, viscosity 400 MPa s.

9) fiber ea tšepe: fiber e otlolohileng ea koporo e entsoeng ka koporo, bopharaφ ke 0.22 limilimithara, bolelele ke 13 limilimithara, matla a tensile ke 2 000 MPa.

Ka mor'a lipatlisiso tse ngata tsa liteko qalong, ho ka etsoa qeto ea hore motsoako oa motsoako oa mocheso o tloaelehileng o phekola konkreite e phahameng ka ho fetisisa ke samente: molora o fofang: phofo ea diminerale: mosi oa silika: lehlabathe: sesebelisoa se fokotsang metsi: phofo ea latex: metsi = 860: 42: 83: 110:980:11:2:210, fiber fiber volume content ke 2%. Eketsa dikahare tsa 0, 0.25%, 0.50%, 0.75%, 1.00% HPMC ea cellulose ether (HPMC) ka karolelano ea motsoako oa motheo Beha liteko tsa ho bapisa ka ho latellana.

1.2 Mokhoa oa teko

Beha boima ba lisebelisoa tse tala tsa phofo ho ea ka karolelano ea ho kopanya 'me u li behe ka har'a HJW-60 shaft e le 'ngoe e rapameng e qobellang motsoako oa konkreite. Qala motsoako ho fihlela junifomo, eketsa metsi 'me u kopanye metsotso e 3, tima motsoako, eketsa fiber e lekantsoeng ea tšepe ebe o qala motsoako hape ka metsotso e 2. E entsoe ka UHPC slurry.

Lintho tsa teko li kenyelletsa metsi, nako ea ho beha, matla a hatellang, matla a ho feto-fetoha ha maemo, matla a axial tensile le boleng ba ho qetela ba ho tiea. Tlhahlobo ea fluidity e khethoa ho ea ka JC/T986-2018 "Cement-based Grouting Materials". Teko ea nako ea ho beha e latela GB / T 1346-2011 "Cement Standard Consistency Consistency Metsi le Ho beha Mokhoa oa Teko ea Nako". Teko ea matla ea ho feto-fetoha ha maemo e khethoa ho latela GB/T50081-2002 "Standard for Test Methods of Mechanical Properties of Ordinary Concrete". Teko ea matla a hatellang, matla a axial tensile le Teko ea boleng bo holimo e lekantsoe ho latela DLT5150-2001 "Hydraulic Concrete Test Regulations".

2. Liphetho tsa liteko

2.1 Liquidity

Liphetho tsa tlhahlobo ea mokelikeli li bonts'a tšusumetso ea litaba tsa HPMC tahlehelong ea metsi a UHPC ha nako e ntse e ea. Ho hlokomeloa ho tsoa ketsahalong ea teko hore ka mor'a hore slurry e se nang cellulose ether e tsosoe ka mokhoa o ts'oanang, bokaholimo bo na le tšekamelo ea ho felloa ke metsi 'meleng le ho phunyeha,' me mokelikeli o lahleheloa ka potlako. , 'me bokhoni ba ho sebetsa bo ntse bo mpefala. Ka mor'a ho eketsa ether ea cellulose, ho ne ho se na letlalo holim'a letlalo, ho lahleheloa ke metsi ka mor'a nako e ne e le nyenyane, 'me ho sebetsa ho ile ha lula ho le molemo. Ka har'a mefuta ea teko, tahlehelo e fokolang ea metsi e ne e le 5 mm ka metsotso e 60. Tlhahlobo ea lintlha tsa tlhahlobo e bontša hore, Palo ea ether ea cellulose ether e tlaase-viscosity e na le phello e fokolang ho metsi a qalang a UHPC, empa e na le tšusumetso e kholo ho lahleheloa ke metsi ka nako. Ha ho se na cellulose ether e kenyelletsoeng, tahlehelo ea fluidity ea UHPC ke 15 mm; Ka keketseho ea HPMC, tahlehelo ea metsi ea seretse e fokotseha; ha tekanyo e le 0.75%, tahlehelo ea metsi ea UHPC ke e nyenyane ka ho fetisisa ka nako, e leng 5mm; ka mor'a moo, ka keketseho ea HPMC, ho lahleheloa ke fluidity ea UHPC ka nako Hoo e batlang e sa fetohe.

KamoraHPMCe tsoakane le UHPC, e ama thepa ea rheological ea UHPC ho tloha likarolong tse peli: e 'ngoe ke hore li-micro-bubble tse ikemetseng li tlisoa ts'ebetsong ea ho hlohlelletsa, e leng se etsang hore molora le molora o fofang le lisebelisoa tse ling e be "phello ea bolo", e leng ho eketsang ho sebetsa ka nako e ts'oanang, lisebelisoa tse ngata tsa cementitious li ka phuthela kakaretso, e le hore kakaretso e ka "emisoa" ka mokhoa o ts'oanang ka slurry, 'me e ka tsamaea ka bolokolohi, likhohlano pakeng tsa lihlopha li fokotseha,' me metsi a eketseha; ea bobeli ke ho eketsa UHPC Matla a kopanetsoeng a fokotsa ho phalla ha metsi. Kaha tlhahlobo e sebelisa HPMC e tlaase-viscosity, karolo ea pele e lekana le karolo ea bobeli, 'me metsi a qalang ha a fetohe haholo, empa ho lahleheloa ke metsi ka mor'a nako ho ka fokotseha. Ho latela tlhahlobo ea liphetho tsa liteko, ho ka tsejoa hore ho eketsa palo e loketseng ea HPMC ho UHPC ho ka ntlafatsa haholo ts'ebetso ea kaho ea UHPC.

2.2 Ho beha nako

Ho latela mokhoa oa phetoho oa nako ea ho beha UHPC e anngoeng ke bongata ba HPMC, ho ka bonoa hore HPMC e bapala karolo ea morao ho UHPC. Ha chelete e le kholoanyane, phello ea ho lieha e bonahala haholoanyane. Ha chelete e le 0.50%, nako ea ho beha seretse ke 55min. Ha ho bapisoa le sehlopha sa taolo (40 min), se eketsehile ka 37,5%, 'me keketseho e ne e ntse e sa totobala. Ha tekanyo e ne e le 1.00%, nako ea ho beha seretse e ne e le 100 min, e neng e le 150% e phahameng ho feta ea sehlopha sa taolo (40 min).

Litšobotsi tsa sebopeho sa limolek'hule tsa cellulose ether li ama phello ea eona ea ho lieha. Sebopeho sa motheo sa limolek'hule ka cellulose ether, ke hore, sebopeho sa selikalikoe sa anhydroglucose, se ka sebetsana le li-ion tsa khalsiamo ho etsa metsoako ea limolek'hule tsa tsoekere-calcium, ho fokotsa nako ea ho kenngoa ha samente clinker hydration reaction. Ca(OH) 2, e fokotsa lebelo la karabelo ea samente ea hydration, ka hona e liehisa ho beha samente.

2.3 Matla a hatellang

Ho tloha kamano pakeng tsa matla a khatello ea li-sampuli tsa UHPC matsatsing a 7 le matsatsi a 28 le litaba tsa HMPC, ho ka bonoa ka ho hlaka hore ho eketsoa ha HPMC butle-butle ho eketsa ho fokotseha ha matla a khatello ea UHPC. 0.25% HPMC, matla a khatello ea UHPC a fokotseha hanyane, 'me tekanyo ea matla a khatello ke 96%. Ho eketsa 0.50% HPMC ha e na phello e totobetseng ho tekanyo ea matla a khatello ea UHPC. Tsoela pele ho kenya HPMC sebakeng sa tšebeliso, UHPC's Matla a khatello a fokotsehile haholo. Ha litaba tsa HPMC li nyolohela ho 1.00%, tekanyo ea matla a khatello e theohetse ho 66%, 'me tahlehelo ea matla e ne e tebile. Ho latela tlhahlobo ea data, ho loketse ho eketsa 0.50% HPMC, mme tahlehelo ea matla a ho hatella e nyane.

HPMC e na le phello e itseng ea ho kenya moea. Keketso ea HPMC e tla baka palo e itseng ea li-microbubble ho UHPC, tse tla fokotsa bongata ba UHPC e sa tsoa tsoakoa. Kamora hore slurry e be thata, porosity e tla eketseha butle-butle mme compactness e tla fokotseha, haholo-holo litaba tsa HPMC. E phahameng. Ho phaella moo, ka ho eketseha ha palo ea HPMC e hlahisitsoeng, ho ntse ho e-na le li-polymers tse ngata tse feto-fetohang ka har'a li-pores tsa UHPC, tse ke keng tsa phetha karolo ea bohlokoa ho ts'ehetso e ntle ea ho tiea le ho hatella ha matrix a motsoako oa cementitious a hatelloa. .Ka hona, ho eketsoa ha HPMC ho fokotsa haholo matla a khatello ea UHPC.

2.4 Matla a feto-fetohang

Ho tloha kamano pakeng tsa matla a flexural a sampuli tsa UHPC matsatsing a 7 le matsatsi a 28 le litaba tsa HMPC, ho ka bonoa hore liphetoho tsa phetoho ea matla a flexural le matla a ho hatella li tšoana, le phetoho ea matla a flexural pakeng tsa 0 le 0.50% ea HMPC ha e tšoane. Ha tlatsetso ea HPMC e ntse e tsoela pele, matla a feto-fetohang a lisampole tsa UHPC a fokotsehile haholo.

Phello ea HPMC ho matla a flexural a UHPC e haholo-holo likarolong tse tharo: cellulose ether e na le liphello tse fokolang le tse kenang moeeng, tse fokotsang matla a ho feto-fetoha ha UHPC; 'me karolo ea boraro ke polima e tenyetsehang e hlahisoang ke cellulose ether, Ho fokotsa ho tiea ha mohlala ho liehisa ho fokotseha ha matla a flexural a mohlala hanyenyane. Ho ba teng ka nako e le 'ngoe ha likarolo tsena tse tharo ho fokotsa matla a khatello ea mohlala oa UHPC hape ho fokotsa matla a ho fetoha.

2.5 Matla a axial tensile le boleng ba ho qetela bo thata

Kamano pakeng tsa matla a tensile ea mehlala ea UHPC ho 7 d le 28 d le litaba tsa HMPC. Ka keketseho ea litaba tsa HPMC, matla a tsitsipano a mehlala ea UHPC a ile a qala ho fetoha hanyane mme a theoha ka potlako. Mokokotlo oa matla a matla o bontša hore ha likahare tsa HPMC setšoantšong li fihla ho 0.50%, boleng ba matla a axial tensile ea mohlala oa UHPC ke 12.2MPa, 'me tekanyo ea matla a tensile ke 103%. Ka keketseho e tsoelang pele ea dikahare tsa HPMC tsa mohlala, axial Boleng ba matla a bohareng bo ile ba qala ho theoha haholo. Ha litaba tsa HPMC tsa mohlala e ne e le 0.75% le 1.00%, tekanyo ea matla a ho tsitsa e ne e le 94% le 78%, ka ho latellana, e neng e le ka tlaase ho matla a axial tensile ea UHPC ntle le HPMC.

Ho tloha kamanong e teng pakeng tsa litekanyetso tsa ho qetela tsa lisampole tsa UHPC matsatsing a 7 le matsatsi a 28 le litaba tsa HMPC, ho ka bonoa hore litekanyetso tsa ho qetela li batla li sa fetohe ka ho eketseha ha cellulose ether qalong, le ha litaba tsa cellulose ether e fihla ho 0.50% mme e qala ho theoha ka potlako.

Phello ea palo ea tlatsetso ea HPMC ho matla a axial tensile le boleng bo phahameng ba ho tiea ba mehlala ea UHPC e bonts'a mokhoa oa ho boloka o batla o sa fetohe ebe o fokotseha. Lebaka le ka sehloohong ke hore HPMC e ka thehoa ka ho toba pakeng tsa likaroloana tsa samente tse nang le hydrated Lera la ho tiisa filimi ea polymer e sa keneleng metsi e phetha karolo ea ho tiisa, e le hore metsi a itseng a bolokehe ho UHPC, e fanang ka metsi a hlokahalang bakeng sa nts'etsopele e tsoelang pele ea metsi a eketsehileng. ea samente, ka tsela eo e ntlafatsa matla a samente. Ho eketsoa ha HPMC ho ntlafatsa Khokahano ea UHPC e fana ka slurry ka ho feto-fetoha ha maemo, e leng se etsang hore UHPC e ikamahanye ka botlalo le shrinkage le deformation ea thepa ea motheo, 'me e ntlafatsa hanyenyane matla a thata a UHPC. Leha ho le joalo, ha litaba tsa HPMC li feta boleng ba bohlokoa, moea o kentsoeng o ama matla a mohlala. Litlamorao tse mpe butle-butle li ile tsa bapala karolo e ka sehloohong, 'me matla a axial tensile le boleng ba ho qetela ba setšoantšo bo ile ba qala ho fokotseha.

3. Qetello

1) HPMC e ka ntlafatsa haholo ts'ebetso ea ts'ebetso ea mocheso o tloaelehileng oa ho phekola UHPC, ea lelefatsa nako ea eona ea coagulation le ho fokotsa tahlehelo ea metsi ea UHPC e sa tsoa tsoakoa ha nako e ntse e ea.

2) Ho eketsoa ha HPMC ho hlahisa palo e itseng ea lipompong tse nyane nakong ea ts'ebetso ea slurry. Haeba palo e le kholo haholo, li-bubble li tla bokellana haholo ebe li etsa li-bubble tse kholoanyane. The slurry e momahaneng haholo, 'me li-bubble ha li khone ho phalla le ho phunyeha. Li-pores tsa UHPC tse thata li fokotseha; ho phaella moo, polymer e feto-fetohang e hlahisoang ke HPMC e ke ke ea fana ka tšehetso e thata ha e le tlas'a khatello, 'me matla a ho hatella le a flexural a fokotseha haholo.

3) Ho eketsoa ha HPMC ho etsa polasetiki ea UHPC le ho tenyetseha. Matla a axial tensile le boleng ba ho qetela ba li-specimens tsa UHPC ha bo fetohe ka keketseho ea litaba tsa HPMC, empa ha litaba tsa HPMC li feta boleng bo itseng, Matla a axial tensile le litekanyetso tsa ho qetela tsa ho tsieleha li fokotseha haholo.

4) Ha u lokisetsa mocheso o tloaelehileng oa ho phekola UHPC, tekanyo ea HPMC e lokela ho laoloa ka thata. Ha tekanyo e le 0.50%, kamano pakeng tsa ts'ebetso ea ho sebetsa le thepa ea mochine ea mocheso o tloaelehileng oa ho phekola UHPC e ka hokahanngoa hantle.