Cement - Superplasticizer Ntau Txoj Haujlwm

Niaj hnub nimno concretes yuav luag ib txwm muaj cov tshuaj ntxiv, ib qho hauv cov ntawv ntxhia lossis cov ntawv sau tshuaj. Tshwj xeeb, cov tshuaj lom neeg kho tshuab xws li cov ntsuas dej thiab cov teeb tsa cov khoom siv tsis zoo siv los txhim kho cov khoom ntawm cov pob zeb tshiab thiab tawv tawv.

Ib qho 'Tshuaj Lom Neeg Siv Tshuaj Ntaus "yog ib qho tshuaj ntxiv rau hauv cov qhob sib xyaw ua kom zoo dua qub cov khoom vaj tse pob zeb nyob rau hauv lub xeev tshiab lossis tawv tawv. Qhov no tsis suav cov xim pleev lossis pleev xim. ACI 116 R [2000] txhais lub sij hawm admixture raws li 'cov khoom siv uas tsis yog dej, sib sau ua ke, hydraulic cement, thiab fiber ntau ntxiv, siv los ua cov khoom xyaw ntawm cov pob zeb ua lossis pob zeb, thiab ntxiv rau cov khoom siv tam sim ntawd ua ntej lossis thaum lub sijhawm nws sib xyaw ua ke '.

Tus nab npawb ntawm cov hom tshuaj admixtures siv rau kev ua vaj tse. Lub hom phiaj siv tshuaj dav dav suav nrog cov uas txo cov kev xav tau dej rau qhov ua haujlwm (hu ua 'cov tuav dej'), cov pa nkag rau hauv av rau kev tiv thaiv kom khov thiab yaj ua haujlwm (hu ua 'air entrainers'), thiab cov chemical uas tswj hwm lub sijhawm teeb tsa thiab lub zog nce tus nqi ntawm cov pob zeb (hu ua 'accelerators' thiab 'retarders'). Sib nrug los ntawm cov tshuaj no, muaj lwm tus rau cov laj thawj tshwj xeeb - namely, viscosity hloov kho cov kab mob, shrinkage txo cov tshuaj lom neeg, kev ua kom tsis haum tshuaj corrosion, thiab alkali-silica cov tshuaj tiv thaiv txo cov admixtures.