Cov kev hloov tshiab hauv polycarboxylic acid dispersants
Sep 13, 2023
Cov kev hloov tshiab hauv polycarboxylic acid dispersants
Hauv kev lag luam pob zeb, kev siv cov tshuaj sib xyaw ua ke los txhim kho kev ua tau zoo ntawm kev ua vaj tse yog ib qho kev siv dav siv. Air-entraining agents, cov neeg sawv cev thaum ntxov, thiab cov dej reducers tau tag nrho cov khoom muaj txiaj ntsig zoo rau cov neeg tsim khoom ua vaj tse. Qee lub sij hawm, cov dej reducers yog tshwj xeeb tshaj yog pab tau kom ua tau raws li ob qho kev sib tw - kev ua haujlwm zoo uas yuav tsum tau ua thaum lub sij hawm ua cov pob zeb, thiab cov dej qis-cement ratio tsim nyog rau durability thiab lwm yam hardening yuav tsum tau.
Lo lus "dej reducer" tau siv ntau xyoo los piav txog cov khoom no. Hauv ASTM C494, cov dej txo qis tau muab faib ua ntau pawg: Hom A cov dej txo qis (ib txwm), Hom D dej-txo thiab cov khoom siv rov qab, Hom E dej-txo thiab ua kom nrawm ntxiv, Hom F siab-ntau cov dej txo qis, thiab Hom G siab. - Ntau yam dej reducers thiab retarding admixtures.
Tsis tas li ntawd, ASTM (American Society for Testing and Materials) suav nrog cov khoom siv tshuaj lom neeg siv hauv kev tsim cov pob zeb ntws hauv ASTM C1017. Lub hom phiaj ntawm tus txheej txheem no yog yuav ua li cas siv cov tshuaj admixtures hauv kev tsim cov pob zeb sib xyaw ua kom siab tsis txhob txo cov dej siv. Feem ntau, cov tshuaj sib xyaw ua ke tau cais raws li Hom F thiab G hauv ASTM C494 tau teev tseg hauv ASTM C1017 rau kev tsim cov pob zeb ntws. Cov dej ntau ntau cov dej no tsis yog tsuas yog txo cov dej xwb tab sis kuj cuam tshuam cov cement hais. Cov nyhuv dispersion no tuaj yeem tsis tsuas yog txo cov dej siv xwb tab sis kuj tsim kom muaj kev poob qis dua, lossis ob qho tib si. Yog li ntawd, cov khoom siv dej ntau ntau no muab kev yooj yim dua rau hauv daim ntawv thov thiab yog cov khoom muaj txiaj ntsig ntau dua.
Zuag qhia tag nrho, chemical admixtures zoo li dej reducers tau hloov pauv kev lag luam pob zeb los ntawm kev txhim kho pob zeb ua haujlwm thaum ua kom muaj txiaj ntsig zoo thiab ua kom zoo dua cov khoom tiav. Nrog kev nce qib zoo li no, peb tsuas tuaj yeem cia siab tias yuav txuas ntxiv kev loj hlob thiab kev tsim kho tshiab hauv kev lag luam.
