• Nagrockienė, Džigita
• Girskas, Giedrius

Abstract

<jats:p>The paper reports the effect of the synthetic zeolite admixture on the viscosity of cement paste. Materials include Portland cement CEM I 42.5 R, synthetic zeolite obtained through low-temperature synthesis under laboratory conditions, polycarboxylate ester based supeplasticizer Muraplast FK 63.30 and tap water. Three compositions of cement paste were made adding 0%, 5%, and 10 wt% of synthetic zeolite. A rotating cylinder viscometer was used for measuring the consistence of the paste; viscosity was measured employing vibrational viscometer SV–10. The consistency test on cement paste showed that spread with no addition of synthetic zeolite made 149 mm, containing 5% of synthetic zeolite the slump was 85 mm and containing 10% of synthetic zeolite spread was 70 mm. The viscosity test also indicated that for the period of 30 minutes, changes in the viscosity of cement paste were as follows: 81.11 mPa s with no addition of synthetic zeolite, 746.5 mPa s containing 5% of synthetic zeolite and 827.1 mPa s containing 10% of synthetic zeolite. Data on the viscosity of cement paste were statistically processed applying software Statistica. Dispersion diagrams demonstrate changes in the viscosity of cement paste adding from 0 to 10 wt% of synthetic zeolite. Taking into account synthetic zeolite, the following correlation coefficients were calculated: 0% – 0.938, 5% – 0.967, 10% – 0.988. The coefficients of determination made 0% – 0,880, 5% – 0,935, 10% – 0,976. Equations for a dependent variable were produced by regression analysis. Santrauka Šio darbo tikslas – nustatyti, kokią įtaką cemento tešlos klampumui turi sintetinio ceolito priedas. Naudotos šios medžiagos: portlandcementis CEM I 42,5 R, sintetinis ceolitas, gautas laboratorijoje atliekant žematemperatūrę sintezę, superplastiklis Muraplast FK 63.30 multikarboksilato esterio pagrindu ir vandentiekio vanduo. Buvo maišomos trijų sudėčių cemento tešlos dedant 0 %, 5 %, 10 % sintetinio ceolito priedo nuo cemento masės. Cemento tešlos konsistencijai nustatyti buvo naudojamas Sutardo viskozimetras, klampumui – vibroviskozimetras SV-10. Atlikus cemento tešlos konsistencijos bandymą nustatyta, kad be sintetinio ceolito priedo cemento tešlos pasklidimas – 149 mm, su 5 % sintetinio ceolito priedu – 85 mm, 10 % – 70 mm. Nustačius cemento tešlos klampumą gauta, kad be sintetinio ceolito priedo cemento tešlos klampumas per 30 minučių kinta 81,11 mPas, su 5 % priedo – 746,5 mPas, 10 % – 827,1 mPas. Cemento tešlos klampumo tyrimo duomenys buvo statistiškai apdorojami kompiuterine programa „Statistica“. Šiame darbe pateikiamos sklaidos diagramos, kuriose pavaizduota, kaip kinta cemento tešlos klampumas laiko atžvilgiu naudojant sintetinio ceolito priedą nuo 0 iki 10 %. Nustatyti korealiacijos koeficinetai: 0 % – 0,9380, 5 % – 0,9669, 10 % – 0,9881, bei determinacijos koeficientai: 0 % – 0,8798, 5 % – 0,9348, 10 % – 0,9763. Atlikus regresinę analizę buvo gautos priklausomybių lygtys.</jats:p>

Topics

• dispersion
• cement
• viscosity
• ester