INFLUENCE OF VARIOUS CLAY PARTICLES ON EFFECTIVENESS OF POLYCARBOXYLATE SUPERPLASTICIZER AND PROPERTIES OF CEMENT STONE
Keywords:
polycarboxylate superplasticizer, sand, clay particles, montmorillonite, hydromica, kaolinite, cement paste, cement stone, cement stone structure, high-performance concreteAbstract
Influence of impurities of clay minerals from sands on the efficiency of polycarboxylate superplasticizers,
the properties of cement paste and stone was studied. For the study, the sands of various deposits of
the Chelyabinsk region were taken, which contained various clay minerals: montmorillonite, hydromica
and kaolin. Research results of phase composition of the clay are presented in this article.
The study was performed using modeling cement stone of concrete and was carried out using
mathematical planning of the experiment, where the main factors were: the amount of superplasticizer
from 0 to 0.8% and the amount of clayey from 0 to 4 %. The effect of these factors on fluidity
was assessed by slump test of the cement paste, and influence on strength and porosity by cubic
samples of cement stone with an edge of 20 mm. The study of the phase composition of clay impurities
from sands and the structural features of the obtained cement stone was carried out using derivatography,
X-ray phase analysis and electron microscopy.
It has been established that the strength of the cement stone and effectiveness of the polycarboxylate
superplasticizer more reduce the clay mineral montmorillonite, and clay minerals containing
hydromica or kaolinite do not significantly affect these parameters. Therefore, sands with clay
impurities up to 2 % consisting of hydromica or kaolinite are permissible to be used in order to obtain
even high-performance concrete. However, to ensure high efficiency of polycarboxylate superplasticizers,
increased strength and durability of concrete on cement binders, it is recommended to
use washed sands or sands with clay content less than 1 %.
Additionally, it was revealed that the polycarboxylate superplasticizer contributes to the formation
of the structure of cement stone from amorphous highly basic calcium hydrosilicates, which
are characterized by increased durability and, consequently, durability.
References
Hirata, T. A cement dispersant. JP Patent 84,2022, 1981, S59–018338.
Lei, L. A concept for a polycarboxylate superplasticizer
possessing enhanced clay tolerance /L. Lei, J. Plank // Cement and Concrete Research. – 2012. – V. 42, № 10. – P. 1299–1306.
Effects of polyethylene oxide chains on the performance
of polycarboxylate-type water-reducers / С.Z. Li, N.Q. Feng, Y.D. Li, R. Chen // Cement and Concrete Research. – 2005. – V. 35, № 5. – P. 867–873.
Plank, J. Synthesis and performance of methacrylic ester based polycarboxylate superplasticizers possessing hydroxy terminated polyethylene glycol side chain / J. Plank, K. Pollmann, N. Zouaoui,
P.R. Andres, C. Schaefer // Cement and Concrete Research.
– 2008. – V. 38, № 10. – P. 1210–1216.
Liu, S. Swelling inhibition by polyglycols in montmorillonite dispersions / S. Liu, X. Mo, C. Zhang // J. Dispers. Sci. Technol. – 2004. – V. 25, № 1. – P. 63–66.
Plank, J. Fundamental mechanisms for polycarboxylate
intercalation into C3A hydrate phases and the role of sulfate present in cement / J. Plank, D. Zhimin, H. Keller, F. v. Hossle, W. Seidl // Cement and Concrete Research. – 2010. – V. 40, № 1. – P. 45–57.
Plank, J. Preparation and characterization of new Ca-Al-polycarboxylate layered double hydroxides / J. Plank, Z. Dai, P.R. Andres // Materials Letters. – 2006. – V. 60. – P. 3614–3617.
Chemical admixtures – Chemistry, applications and their impact on concrete microstructure and durability / J. Plank, E. Sakai, C.W. Miao et al. // Cement and Concrete Research. – 2015. – V. 78. –
P. 81–99.
Xiong, L. Effect of typical clay upon the dispersion performance of polycarboxylate superplasticizer / L. Xiong, G. Zheng, Y. Bi, C. Fu // International Conference on Materials, Environmental and Biological
Engineering (MEBE 2015). – Atlantis Press, 2015. – P. 226–229.
Вовк, А.И. Суперпластификаторы в бетоне: анализ химии процессов / А.И. Вовк // Технология бетонов. – 2007. – № 3. – С. 2–3.
Вовк, А.И. Гидратация трехкальциевого алюмината C3A и смесей C3A-гипс в присутствии ПАВ: адсорбция или поверхностное фазообразование? / А.И. Вовк // Коллоидный журнал. – 2000. – Т. 62, № 1. – С. 31–38.
Вовк, А.И. Механизм адсорбции суперпластификаторов на силикатных и алюминатных компонентах портландцемента / А.И. Вовк // Коллоидный журнал. – 2000. – Т. 62, № 3. – С. 303–308.
Цементные тяжелые бетоны для строительства скоростных автомобильных дорог / Л.Я. Крамар, А.И. Кудяков, Б.Я. Трофимов, К.В. Шулдяков // Вестник ТГАСУ. – 2017. – № 4
(63). – С. 147–158.
Рамачандран, В. Наука о бетоне: физико-химическое бетоноведение / В. Рамачандран, Р. Фельдман, Дж. Бодуэн; пер. с англ. Т.И. Розенберг, Ю.Б. Ратиновой; под ред. В.Б. Ратинова. –
М.: Стройиздат, 1986. – 278 с.
Горшков, В.С. Методы физико-химического анализа вяжущих веществ: учебное пособие / В.С. Горшков, В.В Тимашев, В.Г. Савельев. – М.: Высш. школа, 1981. – 335 с.
Влияние водоцементного отношения и суперпластификаторов на процессы тепловыделения, гидратации и твердения цемента / И.М. Иванов, Д.В. Матвеев, А.А. Орлов, Л.Я. Крамар // Вестник ЮУрГУ. Серия «Строи-
тельство и архитектура». – 2017. – Т. 17, № 2. – С. 42–49.
