HPMC ntawm lub zog ntawm cov cement mortar

Hydroxypropyl Methylcellulose (HPMC)yog ib qho cellulose ether uas tsis yog ionic siv dav hauv cov ntaub ntawv siv hauv kev tsim kho, tshwj xeeb tshaj yog hauv cov cement mortar. Nws ua lub luag haujlwm tseem ceeb hauv kev tswj hwm kev ua haujlwm ntawm mortar vim nws khaws dej zoo, thickening, lubricity thiab zaj duab xis-tsim cov khoom. Txawm li cas los xij, txawm hais tias kev ntxiv HPMC tuaj yeem txhim kho kev ua haujlwm ntawm mortar, nws kuj tseem yuav muaj qee qhov cuam tshuam rau lub zog ntawm cement mortar.

1. Cov khoom siv yooj yim thiab cov txheej txheem ntawm kev ua haujlwm ntawm HPMC

HPMC yog cov khoom siv polymer uas yaj tau hauv dej uas tau npaj los ntawm kev sib xyaw cov tshuaj methyl thiab hydroxypropyl pawg rau hauv cov cellulose ntuj. Nws cov qauv molecular muaj ntau pawg hydrophilic, ua rau nws tsim cov kua colloidal hauv dej thiab muaj peev xwm ua kom tuab thiab khaws dej tau zoo.

Hauv cov cement mortar, HPMC feem ntau ua lub luag haujlwm hauv qab no:

Kev khaws dej: HPMC tuaj yeem txo qhov dej poob hauv cov mortar, ncua cov tshuaj tiv thaiv cement hydration, thiab muab sijhawm txaus rau cement hydration.

Txhim kho kev ua haujlwm tau zoo: Txhim kho kev ua haujlwm ntawm kev tsim kho los ntawm kev txhim kho kev nplaum thiab kev ntws ntawm cov mortar.

Cov nyhuv qeeb: HPMC muaj qee qhov kev ncua sijhawm rau cov txheej txheem hydration ntawm cement vim nws cuam tshuam kev sib kis sai ntawm dej.

Cov nyhuv tsim zaj duab xis: Ib zaj duab xis nyias nyias raug tsim thaum lub sijhawm ziab kom txhim kho qhov tawg tsis kam thiab kev ywj pheej ntawm cov mortar.

2. Cov nyhuv ntawm HPMC rau lub zog ntawm cov av nplaum

Txawm hais tias kev qhia txog HPMC txhim kho kev ua haujlwm ntawm cov mortar, nws muaj qee qhov cuam tshuam tsis zoo rau lub zog kho tshuab ntawm cov mortar (tshwj xeeb tshaj yog lub zog compressive thiab lub zog flexural). Nws yog feem ntau cuam tshuam rau hauv cov hauv qab no:

Kev ncua cov tshuaj tiv thaiv dej: Txawm hais tias qhov cuam tshuam ntawm HPMC ua rau muaj dej ntau ntawm cov cement thaum ntxov, nws qhov qhwv rau ntawm qhov chaw ntawm cov cement yuav cuam tshuam kev nkag mus ntxiv ntawm dej, yog li ncua qhov kev nqus dej ntawm cov cement thiab ua rau qeeb qeeb ntawm kev loj hlob ntawm lub zog thaum ntxov.

Kev tsim cov npuas: HPMC yooj yim rau kev qhia cua thaum lub sijhawm sib tov, ua rau muaj ntau lub npuas me me tsim hauv cov mortar. Cov qhov sib txawv no dhau los ua micropores tom qab ua kom tawv, ua rau lub zog thiab qhov ceev ntawm cov mortar qaug zog.

Kev cuam tshuam rau qhov sib piv ntawm dej thiab cov khoom sib txuas: HPMC yuav cuam tshuam rau qhov fluidity ntawm cov cement paste thaum nws nqus dej. Yuav kom ua tiav qhov fluidity zoo tshaj plaws thaum lub sijhawm tsim kho, yuav tsum ntxiv dej ntau dua, yog li ua rau qhov sib piv ntawm dej thiab cov khoom sib txuas nce ntxiv thiab txo qhov zog kawg.

Kev cuam tshuam rau cov qauv ntawm cov khoom siv cement hydration: HPMC yuav cuam tshuam nrog qee cov khoom siv hydration thaum lub sijhawm hydration, hloov lawv cov qauv siv lead ua thiab kev faib tawm qhov chaw, yog li cuam tshuam rau cov khoom siv kho tshuab.

3. Qhov cuam tshuam ntawm HPMC koob tshuaj rau lub zog

Qhov cuam tshuam ntawm HPMC rau lub zog ntawm cov cement mortar qhia txog qee qhov kev tsis tu ncua:

Cov tshuaj tsawg (<0.1%): me ntsis cuam tshuam rau lub zog, feem ntau txhim kho kev khaws dej thiab kev ua haujlwm;

Cov koob tshuaj nruab nrab (0.1% ~ 0.3%): kev ua haujlwm ntawm kev tsim kho tau zoo dua, tab sis lub zog pib poob qis;

Kev siv tshuaj ntau (> 0.3%): lub zog txo qis heev, tshwj xeeb tshaj yog lub zog thaum ntxov txo qis heev, uas yuav ua rau muaj kev puas tsuaj rau kev tsim kho thaum ntxov.

Kev tswj hwm qhov ntau ntawm HPMC ntxiv yog qhov tseem ceeb rau kev tswj hwm lub zog mortar thaum ua kom ntseeg tau tias kev ua haujlwm ntawm kev tsim kho.

4. Cov lus qhia txog kev txhim kho

Yuav kom sib npaug ntawm kev sib raug zoo ntawm kev tsim kho thiab cov khoom siv kho tshuab, kev ua kom zoo dua tuaj yeem ua tiav los ntawm cov hauv qab no:

Txhim kho qhov koob tshuaj: Txheeb xyuas qhov zoo tshaj plaws HPMC koob tshuaj los ntawm kev sim kom ntseeg tau tias kev ua haujlwm ntawm kev tsim kho thiab txo qis cov teebmeem tsis zoo ntawm lub zog.

Cov tshuaj sib xyaw ua ke: Siv cov tshuaj sib xyaw uas tuaj yeem txhim kho lub zog, xws li silica fume, fly ash thiab lwm yam tshuaj sib xyaw ua ke, los txhim kho qhov ceev ntawm cov mortar.

Xaiv cov khoom HPMC nrog viscosity tsim nyog: HPMC ntawm cov qib viscosity sib txawv muaj cov teebmeem sib txawv rau kev ua haujlwm ntawm cov mortar. viscosity siab dhau yuav ua rau muaj npuas ntau ntxiv, thiab viscosity nruab nrab yog qhov zoo dua rau kev sib npaug ntawm kev ua haujlwm tag nrho.

Tswj qhov sib piv ntawm dej thiab cement thaum lub sijhawm tsim kho: Sim txo cov dej ntxiv uas siv vim yog qhov yuav tsum tau ua kom du kom tsis txhob muaj qhov sib piv ntawm dej thiab cement ntau dhau uas cuam tshuam rau lub zog.

HPMCmuaj qhov zoo tseem ceeb hauv kev txhim kho kev ua tau zoo ntawm cov cement mortar, tab sis nws qhov cuam tshuam tsis zoo rau lub zog mortar, tshwj xeeb tshaj yog lub zog thaum ntxov, tsis tuaj yeem tsis quav ntsej. Kev siv HPMC kom tsim nyog, kev tswj hwm nws cov koob tshuaj, thiab kev sib xyaw nrog lwm yam kev ntsuas kev ua kom zoo dua tuaj yeem ua kom ntseeg tau tias lub zog ntawm cov qauv ua tau raws li qhov xav tau engineering thaum txhim kho kev ua haujlwm ntawm kev tsim kho. Kev tshawb fawb yav tom ntej tuaj yeem tshawb nrhiav ntxiv txog cov txheej txheem synergistic ntawm HPMC thiab lwm yam admixtures los muab cov lus qhia ntxiv rau kev tshawb fawb rau nws daim ntawv thov hauv cov ntaub ntawv tsim kho.