Vim li cas qhov nthuav dav ntawm pob zeb nrog polycarboxylic superplasticizer me me?

Thaum cov cement paste sib xyaw nrog polycarboxylic superplasticizer (PCE) muaj qhov muaj dej ntau, tab sis cov pob zeb qhia tias tsis tshua muaj kev sib kis lossis thaum cov pob zeb tshiab muaj qhov pib poob siab tab sis sai sai poob haujlwm, nws feem ntau qhia tias tsis sib haum xeeb ntawm cov cement thiab superplasticizer. Qhov laj thawj ntawm cov teeb meem no tuaj yeem taug qab mus rau ob yam tseem ceeb:

1. Kev siv tsis txaus ntawm Superplasticizer

Qhov ntau npaum li cas ntawm PCE nyob rau hauv cov pob zeb yuav qis dua qhov saturation point, tiv thaiv cov khoom siv los ntawm kev siv nws cov dej-txo thiab slump-retention capabilities. Hauv kev ntsuam xyuas cov cement paste fluidity, nws yog ib qho tseem ceeb rau kev ntsuas tsis tau tsuas yog qhov pib fluidity tab sis kuj yog qhov fluidity poob lub sij hawm, feem ntau ntawm 30 feeb lossis 1 teev.

Qhov kev pom zoo ntawm PCE tau txiav txim siab nyob rau ntawm qhov chaw uas qhov dej tsis muaj zog ntxiv lawm nrog kev siv tshuaj ntau ntxiv, thiab qhov twg qhov dej ntws dhau lub sijhawm tsawg. Qhov kev noj zaub mov zoo no ua haujlwm raws li lub ntsiab lus saturation thiab muab kev taw qhia rau qhov tsim nyog npaum li cas hauv cov pob zeb sib xyaw.

Piv txwv li: Kev txiav txim siab ntawm Saturation Point

Daim duab 1 qhia txog kev txiav txim siab ntawm qhov saturation point. Rau superplasticizers I, II, thiab IV, saturation ntau npaum li cas los ntawm thawj zaug cement

paste fluidity yog {{0}}.5%. Txawm li cas los xij, xav txog qhov poob ntawm 1-teev fluidity poob, qhov saturation ntau npaum li cas rau superplasticizers I thiab II yuav tsum tau teem rau ntawm 0.7%. Rau superplasticizer IV, qhov tseem ceeb fluidity poob tseem nyob ntawm 0.7%, qhia tias yog cov pob zeb tau npaj nrog 0.5% ntau npaum li cas, thaum qhov pib poob qis yuav siab, kev ua haujlwm yuav degrade sai.

2. Teeb meem nrog lwm yam Raw Material Quality Parameters lossis Mix Design

Yog tias qhov teeb meem hais txog kev noj tshuaj saum toj no tsis suav nrog, kev ua haujlwm tsis zoo ntawm cov pob zeb ua haujlwm yuav raug ntaus nqi los ntawm lwm cov khoom siv raw lossis cov khoom sib xyaw ua ke. Cov xwm txheej no suav nrog:

Aggregate contamination:Cov ntsiab lus av nkos thiab av nplaum lumps hauv aggregates.

Xuab zeb zoo:Fine aggregate fineness modulus.

Mineral admixtures:Kev thov dej thiab kev sib raug zoo nrog PCE.

Cov khoom siv cementitious, xuab zeb ratio, thiab dej ntsiab lus.

Ntawm cov no, cov ntsiab lus av nkos hauv cov xuab zeb muaj qhov tseem ceeb tshaj plaws thiab feem ntau cuam tshuam rau kev ua haujlwm ua vaj tse thaum siv PCE. PCE yog rhiab heev rau cov av nkos, thiab cov av nkos cov ntsiab lus yuav tsum tsis pub tshaj 2%; txwv tsis pub, kev ua tiav kev ua haujlwm zoo siab ua haujlwm yuav nyuaj.

Piv txwv li: Kev cuam tshuam ntawm Sand Mud Content

Table 1 qhia txog kev cuam tshuam ntawm cov av nkos cov ntsiab lus ntawm cov pob zeb slump thiab PCE ntau npaum li cas (raws li cov ntaub ntawv tseeb los ntawm cov haujlwm thoob ntiaj teb). Thaum cov av nkos cov ntsiab lus nce ntawm 1.5% mus rau 3.5%, cov pob zeb tshiab poob qis los ntawm 195 hli mus rau 100 hli, tsis muaj qhov ntsuas tau. Hloov pauv, txo cov xuab zeb av nkos los ntawm 1.5% mus rau 1.0% tso cai rau PCE ntau npaum li cas los ntawm 1.9% mus rau 1.4% thaum tswj kev ua haujlwm zoo ib yam. Qhov no qhia txog qhov cuam tshuam loj ntawm cov xuab zeb zoo ntawm PCE kev ua haujlwm.

Tam sim no, ntau thaj tsam hauv Suav teb ntsib qhov tsis txaus ntawm cov xuab zeb zoo, nrog cov av nkos thiab cov av nplaum cov ntsiab lus hauv cov xuab zeb feem ntau dhau qhov kev txwv. Qhov no tau dhau los ua qhov cuam tshuam loj rau kev siv dav dav ntawm PCE.

Indicators for Testing Superplasticizers

Superplasticizer ntsuas ntsuas poob rau hauv ob pawg loj:

Concrete Performance Indicators:Cov no ntsuas qhov ua tau zoo ntawm kev sim cov pob zeb sib piv rau kev siv cov pob zeb ua raws li cov qauv kev sim (piv txwv li, cov khoom siv raw zoo thiab cov qauv sib xyaw ua ke raws li cov qauv xav tau). Cov ntsuas no ntsuas qhov zoo ntawm cov khoom sib txawv.

Homogeneity Indicators:Cov tshuaj ntsuam xyuas cov khoom siv ntawm cov khoom siv nws tus kheej thiab siv los xyuas kom meej cov khoom zoo sib xws.

Hauv kev tsim khoom, vim muaj qhov sib txawv tseem ceeb ntawm kev tsim khoom thiab cov qauv kev sim, nws raug nquahu kom tsom mus rau homogeneity ntsuas rau txhua pawg. Cov ntsuas kev ua tau zoo ntawm cov pob zeb tuaj yeem raug xa mus los ntawm lub Hoobkas lossis hom kev tshuaj xyuas cov ntaub ntawv thiab txheeb xyuas thaum lub sijhawm sim sib xyaw siv cov qauv sib xyaw tiag tiag.

Ntsiab Homogeneity Indicators

Qhov tseem ceeb tshaj plaws homogeneity ntsuas yog cov ntsiab lus thiab cov cement paste fluidity, nrog rau kev txiav txim siab ntawm qhov saturation point npaum li cas. Raws li tau hais ua ntej lawm, kev ua haujlwm siab hauv cov cement paste tsis tas yuav txhais mus rau cov pob zeb loj. Txawm li cas los xij, nws qhia tau hais tias thawj qhov ua rau kev poob qis yog tsis muaj feem xyuam rau cov cement lossis admixture compatibility. Qhov zoo ntawm lwm cov khoom siv raw thiab cov qauv tsim tsis sib xyaw yuav tsum tau tshawb xyuas tam sim.

Tsis tas li ntawd, PCE ntau npaum li cas yuav tsum tsis txhob poob qis dua qhov saturation point kom siv tag nrho nws cov dej-txo thiab slump-retention capabilities. Qhov no tseem tso cai rau kev txo qis hauv kev siv cov khoom siv cementitious thiab cov nqi tsim khoom ua vaj tse. Xav txog qhov cuam tshuam adsorption ntawm cov khoom paug xws li av nkos hauv cov khoom sib xyaw, qhov tseeb PCE ntau npaum li cas hauv pob zeb yuav tsum tsis txhob qis dua qhov saturation point.